/*
** This function is called after an "ALTER TABLE ... ADD" statement
** has been parsed. Argument pColDef contains the text of the new
** column definition.
**
** The Table structure pParse->pNewTable was extended to include
** the new column during parsing.
*/
void sqlite3AlterFinishAddColumn(Parse *pParse, Token *pColDef){
Table *pNew; /* Copy of pParse->pNewTable */
Table *pTab; /* Table being altered */
int iDb; /* Database number */
const char *zDb; /* Database name */
const char *zTab; /* Table name */
char *zCol; /* Null-terminated column definition */
Column *pCol; /* The new column */
Expr *pDflt; /* Default value for the new column */
sqlite3 *db; /* The database connection; */
db = pParse->db;
if( pParse->nErr || db->mallocFailed ) return;
pNew = pParse->pNewTable;
assert( pNew );
assert( sqlite3BtreeHoldsAllMutexes(db) );
iDb = sqlite3SchemaToIndex(db, pNew->pSchema);
zDb = db->aDb[iDb].zName;
zTab = &pNew->zName[16]; /* Skip the "sqlite_altertab_" prefix on the name */
pCol = &pNew->aCol[pNew->nCol-1];
pDflt = pCol->pDflt;
pTab = sqlite3FindTable(db, zTab, zDb);
assert( pTab );
#ifndef SQLITE_OMIT_AUTHORIZATION
/* Invoke the authorization callback. */
if( sqlite3AuthCheck(pParse, SQLITE_ALTER_TABLE, zDb, pTab->zName, 0) ){
return;
}
#endif
/* If the default value for the new column was specified with a
** literal NULL, then set pDflt to 0. This simplifies checking
** for an SQL NULL default below.
*/
if( pDflt && pDflt->op==TK_NULL ){
pDflt = 0;
}
/* Check that the new column is not specified as PRIMARY KEY or UNIQUE.
** If there is a NOT NULL constraint, then the default value for the
** column must not be NULL.
*/
if( pCol->colFlags & COLFLAG_PRIMKEY ){
sqlite3ErrorMsg(pParse, "Cannot add a PRIMARY KEY column");
return;
}
if( pNew->pIndex ){
sqlite3ErrorMsg(pParse, "Cannot add a UNIQUE column");
return;
}
if( (db->flags&SQLITE_ForeignKeys) && pNew->pFKey && pDflt ){
sqlite3ErrorMsg(pParse,
"Cannot add a REFERENCES column with non-NULL default value");
return;
}
if( pCol->notNull && !pDflt ){
sqlite3ErrorMsg(pParse,
"Cannot add a NOT NULL column with default value NULL");
return;
}
/* Ensure the default expression is something that sqlite3ValueFromExpr()
** can handle (i.e. not CURRENT_TIME etc.)
*/
if( pDflt ){
sqlite3_value *pVal = 0;
int rc;
rc = sqlite3ValueFromExpr(db, pDflt, SQLITE_UTF8, SQLITE_AFF_BLOB, &pVal);
assert( rc==SQLITE_OK || rc==SQLITE_NOMEM );
if( rc!=SQLITE_OK ){
db->mallocFailed = 1;
return;
}
if( !pVal ){
sqlite3ErrorMsg(pParse, "Cannot add a column with non-constant default");
return;
}
sqlite3ValueFree(pVal);
}
/* Modify the CREATE TABLE statement. */
zCol = sqlite3DbStrNDup(db, (char*)pColDef->z, pColDef->n);
if( zCol ){
char *zEnd = &zCol[pColDef->n-1];
int savedDbFlags = db->flags;
while( zEnd>zCol && (*zEnd==';' || sqlite3Isspace(*zEnd)) ){
*zEnd-- = '\0';
}
db->flags |= SQLITE_PreferBuiltin;
sqlite3NestedParse(pParse,
"UPDATE \"%w\".%s SET "
"sql = substr(sql,1,%d) || ', ' || %Q || substr(sql,%d) "
"WHERE type = 'table' AND name = %Q",
zDb, SCHEMA_TABLE(iDb), pNew->addColOffset, zCol, pNew->addColOffset+1,
zTab
);
sqlite3DbFree(db, zCol);
db->flags = savedDbFlags;
}
/* If the default value of the new column is NULL, then set the file
** format to 2. If the default value of the new column is not NULL,
** the file format becomes 3.
*/
sqlite3MinimumFileFormat(pParse, iDb, pDflt ? 3 : 2);
/* Reload the schema of the modified table. */
reloadTableSchema(pParse, pTab, pTab->zName);
}
/*
** This function is called by the parser after the table-name in
** an "ALTER TABLE <table-name> ADD" statement is parsed. Argument
** pSrc is the full-name of the table being altered.
**
** This routine makes a (partial) copy of the Table structure
** for the table being altered and sets Parse.pNewTable to point
** to it. Routines called by the parser as the column definition
** is parsed (i.e. sqlite3AddColumn()) add the new Column data to
** the copy. The copy of the Table structure is deleted by tokenize.c
** after parsing is finished.
**
** Routine sqlite3AlterFinishAddColumn() will be called to complete
** coding the "ALTER TABLE ... ADD" statement.
*/
void sqlite3AlterBeginAddColumn(Parse *pParse, SrcList *pSrc){
Table *pNew;
Table *pTab;
Vdbe *v;
int iDb;
int i;
int nAlloc;
sqlite3 *db = pParse->db;
/* Look up the table being altered. */
assert( pParse->pNewTable==0 );
assert( sqlite3BtreeHoldsAllMutexes(db) );
if( db->mallocFailed ) goto exit_begin_add_column;
pTab = sqlite3LocateTableItem(pParse, 0, &pSrc->a[0]);
if( !pTab ) goto exit_begin_add_column;
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( IsVirtual(pTab) ){
sqlite3ErrorMsg(pParse, "virtual tables may not be altered");
goto exit_begin_add_column;
}
#endif
/* Make sure this is not an attempt to ALTER a view. */
if( pTab->pSelect ){
sqlite3ErrorMsg(pParse, "Cannot add a column to a view");
goto exit_begin_add_column;
}
if( SQLITE_OK!=isSystemTable(pParse, pTab->zName) ){
goto exit_begin_add_column;
}
assert( pTab->addColOffset>0 );
iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
/* Put a copy of the Table struct in Parse.pNewTable for the
** sqlite3AddColumn() function and friends to modify. But modify
** the name by adding an "sqlite_altertab_" prefix. By adding this
** prefix, we insure that the name will not collide with an existing
** table because user table are not allowed to have the "sqlite_"
** prefix on their name.
*/
pNew = (Table*)sqlite3DbMallocZero(db, sizeof(Table));
if( !pNew ) goto exit_begin_add_column;
pParse->pNewTable = pNew;
pNew->nRef = 1;
pNew->nCol = pTab->nCol;
assert( pNew->nCol>0 );
nAlloc = (((pNew->nCol-1)/8)*8)+8;
assert( nAlloc>=pNew->nCol && nAlloc%8==0 && nAlloc-pNew->nCol<8 );
pNew->aCol = (Column*)sqlite3DbMallocZero(db, sizeof(Column)*nAlloc);
pNew->zName = sqlite3MPrintf(db, "sqlite_altertab_%s", pTab->zName);
if( !pNew->aCol || !pNew->zName ){
db->mallocFailed = 1;
goto exit_begin_add_column;
}
memcpy(pNew->aCol, pTab->aCol, sizeof(Column)*pNew->nCol);
for(i=0; i<pNew->nCol; i++){
Column *pCol = &pNew->aCol[i];
pCol->zName = sqlite3DbStrDup(db, pCol->zName);
pCol->zColl = 0;
pCol->zType = 0;
pCol->pDflt = 0;
pCol->zDflt = 0;
}
pNew->pSchema = db->aDb[iDb].pSchema;
pNew->addColOffset = pTab->addColOffset;
pNew->nRef = 1;
/* Begin a transaction and increment the schema cookie. */
sqlite3BeginWriteOperation(pParse, 0, iDb);
v = sqlite3GetVdbe(pParse);
if( !v ) goto exit_begin_add_column;
sqlite3ChangeCookie(pParse, iDb);
exit_begin_add_column:
sqlite3SrcListDelete(db, pSrc);
return;
}
/*
** This is called by the parser when it sees a CREATE TRIGGER statement
** up to the point of the BEGIN before the trigger actions. A Trigger
** structure is generated based on the information available and stored
** in pParse->pNewTrigger. After the trigger actions have been parsed, the
** sqlite3FinishTrigger() function is called to complete the trigger
** construction process.
*/
void sqlite3BeginTrigger(
Parse *pParse, /* The parse context of the CREATE TRIGGER statement */
Token *pName1, /* The name of the trigger */
Token *pName2, /* The name of the trigger */
int tr_tm, /* One of TK_BEFORE, TK_AFTER, TK_INSTEAD */
int op, /* One of TK_INSERT, TK_UPDATE, TK_DELETE */
IdList *pColumns, /* column list if this is an UPDATE OF trigger */
SrcList *pTableName,/* The name of the table/view the trigger applies to */
Expr *pWhen, /* WHEN clause */
int isTemp, /* True if the TEMPORARY keyword is present */
int noErr /* Suppress errors if the trigger already exists */
){
Trigger *pTrigger = 0; /* The new trigger */
Table *pTab; /* Table that the trigger fires off of */
char *zName = 0; /* Name of the trigger */
sqlite3 *db = pParse->db; /* The database connection */
int iDb; /* The database to store the trigger in */
Token *pName; /* The unqualified db name */
DbFixer sFix; /* State vector for the DB fixer */
int iTabDb; /* Index of the database holding pTab */
assert(pName1 != 0); /* pName1->z might be NULL, but not pName1 itself */
assert(pName2 != 0);
assert(op == TK_INSERT || op == TK_UPDATE || op == TK_DELETE);
assert(op > 0 && op<0xff);
if (isTemp){
/* If TEMP was specified, then the trigger name may not be qualified. */
if (pName2->n>0){
sqlite3ErrorMsg(pParse, "temporary trigger may not have qualified name");
goto trigger_cleanup;
}
iDb = 1;
pName = pName1;
}
else{
/* Figure out the db that the trigger will be created in */
iDb = sqlite3TwoPartName(pParse, pName1, pName2, &pName);
if (iDb < 0){
goto trigger_cleanup;
}
}
if (!pTableName || db->mallocFailed){
goto trigger_cleanup;
}
/* A long-standing parser bug is that this syntax was allowed:
**
** CREATE TRIGGER attached.demo AFTER INSERT ON attached.tab ....
** ^^^^^^^^
**
** To maintain backwards compatibility, ignore the database
** name on pTableName if we are reparsing our of SQLITE_MASTER.
*/
if (db->init.busy && iDb != 1){
sqlite3DbFree(db, pTableName->a[0].zDatabase);
pTableName->a[0].zDatabase = 0;
}
/* If the trigger name was unqualified, and the table is a temp table,
** then set iDb to 1 to create the trigger in the temporary database.
** If sqlite3SrcListLookup() returns 0, indicating the table does not
** exist, the error is caught by the block below.
*/
pTab = sqlite3SrcListLookup(pParse, pTableName);
if (db->init.busy == 0 && pName2->n == 0 && pTab
&& pTab->pSchema == db->aDb[1].pSchema){
iDb = 1;
}
/* Ensure the table name matches database name and that the table exists */
if (db->mallocFailed) goto trigger_cleanup;
assert(pTableName->nSrc == 1);
sqlite3FixInit(&sFix, pParse, iDb, "trigger", pName);
if (sqlite3FixSrcList(&sFix, pTableName)){
goto trigger_cleanup;
}
pTab = sqlite3SrcListLookup(pParse, pTableName);
if (!pTab){
/* The table does not exist. */
if (db->init.iDb == 1){
/* Ticket #3810.
** Normally, whenever a table is dropped, all associated triggers are
** dropped too. But if a TEMP trigger is created on a non-TEMP table
** and the table is dropped by a different database connection, the
** trigger is not visible to the database connection that does the
** drop so the trigger cannot be dropped. This results in an
** "orphaned trigger" - a trigger whose associated table is missing.
*/
db->init.orphanTrigger = 1;
}
goto trigger_cleanup;
}
if (IsVirtual(pTab)){
sqlite3ErrorMsg(pParse, "cannot create triggers on virtual tables");
goto trigger_cleanup;
}
/* Check that the trigger name is not reserved and that no trigger of the
** specified name exists */
zName = sqlite3NameFromToken(db, pName);
if (!zName || SQLITE_OK != sqlite3CheckObjectName(pParse, zName)){
goto trigger_cleanup;
}
assert(sqlite3SchemaMutexHeld(db, iDb, 0));
if (sqlite3HashFind(&(db->aDb[iDb].pSchema->trigHash),
zName, sqlite3Strlen30(zName))){
if (!noErr){
sqlite3ErrorMsg(pParse, "trigger %T already exists", pName);
}
else{
assert(!db->init.busy);
sqlite3CodeVerifySchema(pParse, iDb);
}
goto trigger_cleanup;
}
/* Do not create a trigger on a system table */
if (sqlite3StrNICmp(pTab->zName, "sqlite_", 7) == 0){
sqlite3ErrorMsg(pParse, "cannot create trigger on system table");
pParse->nErr++;
goto trigger_cleanup;
}
/* INSTEAD of triggers are only for views and views only support INSTEAD
** of triggers.
*/
if (pTab->pSelect && tr_tm != TK_INSTEAD){
sqlite3ErrorMsg(pParse, "cannot create %s trigger on view: %S",
(tr_tm == TK_BEFORE) ? "BEFORE" : "AFTER", pTableName, 0);
goto trigger_cleanup;
}
if (!pTab->pSelect && tr_tm == TK_INSTEAD){
sqlite3ErrorMsg(pParse, "cannot create INSTEAD OF"
" trigger on table: %S", pTableName, 0);
goto trigger_cleanup;
}
iTabDb = sqlite3SchemaToIndex(db, pTab->pSchema);
#ifndef SQLITE_OMIT_AUTHORIZATION
{
int code = SQLITE_CREATE_TRIGGER;
const char *zDb = db->aDb[iTabDb].zName;
const char *zDbTrig = isTemp ? db->aDb[1].zName : zDb;
if (iTabDb == 1 || isTemp) code = SQLITE_CREATE_TEMP_TRIGGER;
if (sqlite3AuthCheck(pParse, code, zName, pTab->zName, zDbTrig)){
goto trigger_cleanup;
}
if (sqlite3AuthCheck(pParse, SQLITE_INSERT, SCHEMA_TABLE(iTabDb), 0, zDb)){
goto trigger_cleanup;
}
}
#endif
/* INSTEAD OF triggers can only appear on views and BEFORE triggers
** cannot appear on views. So we might as well translate every
** INSTEAD OF trigger into a BEFORE trigger. It simplifies code
** elsewhere.
*/
if (tr_tm == TK_INSTEAD){
tr_tm = TK_BEFORE;
}
/* Build the Trigger object */
pTrigger = (Trigger*)sqlite3DbMallocZero(db, sizeof(Trigger));
if (pTrigger == 0) goto trigger_cleanup;
pTrigger->zName = zName;
zName = 0;
pTrigger->table = sqlite3DbStrDup(db, pTableName->a[0].zName);
pTrigger->pSchema = db->aDb[iDb].pSchema;
pTrigger->pTabSchema = pTab->pSchema;
pTrigger->op = (u8)op;
pTrigger->tr_tm = tr_tm == TK_BEFORE ? TRIGGER_BEFORE : TRIGGER_AFTER;
pTrigger->pWhen = sqlite3ExprDup(db, pWhen, EXPRDUP_REDUCE);
pTrigger->pColumns = sqlite3IdListDup(db, pColumns);
assert(pParse->pNewTrigger == 0);
pParse->pNewTrigger = pTrigger;
trigger_cleanup:
sqlite3DbFree(db, zName);
sqlite3SrcListDelete(db, pTableName);
sqlite3IdListDelete(db, pColumns);
sqlite3ExprDelete(db, pWhen);
if (!pParse->pNewTrigger){
sqlite3DeleteTrigger(db, pTrigger);
}
else{
assert(pParse->pNewTrigger == pTrigger);
}
}
/*
** Generate code to implement the "ALTER TABLE xxx RENAME TO yyy"
** command.
*/
void sqlite3AlterRenameTable(
Parse *pParse, /* Parser context. */
SrcList *pSrc, /* The table to rename. */
Token *pName /* The new table name. */
){
int iDb; /* Database that contains the table */
char *zDb; /* Name of database iDb */
Table *pTab; /* Table being renamed */
char *zName = 0; /* NULL-terminated version of pName */
sqlite3 *db = pParse->db; /* Database connection */
int nTabName; /* Number of UTF-8 characters in zTabName */
const char *zTabName; /* Original name of the table */
Vdbe *v;
#ifndef SQLITE_OMIT_TRIGGER
char *zWhere = 0; /* Where clause to locate temp triggers */
#endif
VTable *pVTab = 0; /* Non-zero if this is a v-tab with an xRename() */
int savedDbFlags; /* Saved value of db->flags */
savedDbFlags = db->flags;
if( NEVER(db->mallocFailed) ) goto exit_rename_table;
assert( pSrc->nSrc==1 );
assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );
pTab = sqlite3LocateTableItem(pParse, 0, &pSrc->a[0]);
if( !pTab ) goto exit_rename_table;
iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
zDb = db->aDb[iDb].zName;
db->flags |= SQLITE_PreferBuiltin;
/* Get a NULL terminated version of the new table name. */
zName = sqlite3NameFromToken(db, pName);
if( !zName ) goto exit_rename_table;
/* Check that a table or index named 'zName' does not already exist
** in database iDb. If so, this is an error.
*/
if( sqlite3FindTable(db, zName, zDb) || sqlite3FindIndex(db, zName, zDb) ){
sqlite3ErrorMsg(pParse,
"there is already another table or index with this name: %s", zName);
goto exit_rename_table;
}
/* Make sure it is not a system table being altered, or a reserved name
** that the table is being renamed to.
*/
if( SQLITE_OK!=isSystemTable(pParse, pTab->zName) ){
goto exit_rename_table;
}
if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){ goto
exit_rename_table;
}
#ifndef SQLITE_OMIT_VIEW
if( pTab->pSelect ){
sqlite3ErrorMsg(pParse, "view %s may not be altered", pTab->zName);
goto exit_rename_table;
}
#endif
#ifndef SQLITE_OMIT_AUTHORIZATION
/* Invoke the authorization callback. */
if( sqlite3AuthCheck(pParse, SQLITE_ALTER_TABLE, zDb, pTab->zName, 0) ){
goto exit_rename_table;
}
#endif
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( sqlite3ViewGetColumnNames(pParse, pTab) ){
goto exit_rename_table;
}
if( IsVirtual(pTab) ){
pVTab = sqlite3GetVTable(db, pTab);
if( pVTab->pVtab->pModule->xRename==0 ){
pVTab = 0;
}
}
#endif
/* Begin a transaction for database iDb.
** Then modify the schema cookie (since the ALTER TABLE modifies the
** schema). Open a statement transaction if the table is a virtual
** table.
*/
v = sqlite3GetVdbe(pParse);
if( v==0 ){
goto exit_rename_table;
}
sqlite3BeginWriteOperation(pParse, pVTab!=0, iDb);
sqlite3ChangeCookie(pParse, iDb);
/* If this is a virtual table, invoke the xRename() function if
** one is defined. The xRename() callback will modify the names
** of any resources used by the v-table implementation (including other
** SQLite tables) that are identified by the name of the virtual table.
*/
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( pVTab ){
int i = ++pParse->nMem;
sqlite3VdbeLoadString(v, i, zName);
sqlite3VdbeAddOp4(v, OP_VRename, i, 0, 0,(const char*)pVTab, P4_VTAB);
sqlite3MayAbort(pParse);
}
#endif
/* figure out how many UTF-8 characters are in zName */
zTabName = pTab->zName;
nTabName = sqlite3Utf8CharLen(zTabName, -1);
#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
if( db->flags&SQLITE_ForeignKeys ){
/* If foreign-key support is enabled, rewrite the CREATE TABLE
** statements corresponding to all child tables of foreign key constraints
** for which the renamed table is the parent table. */
if( (zWhere=whereForeignKeys(pParse, pTab))!=0 ){
sqlite3NestedParse(pParse,
"UPDATE \"%w\".%s SET "
"sql = sqlite_rename_parent(sql, %Q, %Q) "
"WHERE %s;", zDb, SCHEMA_TABLE(iDb), zTabName, zName, zWhere);
sqlite3DbFree(db, zWhere);
}
}
#endif
/* Modify the sqlite_master table to use the new table name. */
sqlite3NestedParse(pParse,
"UPDATE %Q.%s SET "
#ifdef SQLITE_OMIT_TRIGGER
"sql = sqlite_rename_table(sql, %Q), "
#else
"sql = CASE "
"WHEN type = 'trigger' THEN sqlite_rename_trigger(sql, %Q)"
"ELSE sqlite_rename_table(sql, %Q) END, "
#endif
"tbl_name = %Q, "
"name = CASE "
"WHEN type='table' THEN %Q "
"WHEN name LIKE 'sqlite_autoindex%%' AND type='index' THEN "
"'sqlite_autoindex_' || %Q || substr(name,%d+18) "
"ELSE name END "
"WHERE tbl_name=%Q COLLATE nocase AND "
"(type='table' OR type='index' OR type='trigger');",
zDb, SCHEMA_TABLE(iDb), zName, zName, zName,
#ifndef SQLITE_OMIT_TRIGGER
zName,
#endif
zName, nTabName, zTabName
);
#ifndef SQLITE_OMIT_AUTOINCREMENT
/* If the sqlite_sequence table exists in this database, then update
** it with the new table name.
*/
if( sqlite3FindTable(db, "sqlite_sequence", zDb) ){
sqlite3NestedParse(pParse,
"UPDATE \"%w\".sqlite_sequence set name = %Q WHERE name = %Q",
zDb, zName, pTab->zName);
}
#endif
#ifndef SQLITE_OMIT_TRIGGER
/* If there are TEMP triggers on this table, modify the sqlite_temp_master
** table. Don't do this if the table being ALTERed is itself located in
** the temp database.
*/
if( (zWhere=whereTempTriggers(pParse, pTab))!=0 ){
sqlite3NestedParse(pParse,
"UPDATE sqlite_temp_master SET "
"sql = sqlite_rename_trigger(sql, %Q), "
"tbl_name = %Q "
"WHERE %s;", zName, zName, zWhere);
sqlite3DbFree(db, zWhere);
}
#endif
#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
if( db->flags&SQLITE_ForeignKeys ){
FKey *p;
for(p=sqlite3FkReferences(pTab); p; p=p->pNextTo){
Table *pFrom = p->pFrom;
if( pFrom!=pTab ){
reloadTableSchema(pParse, p->pFrom, pFrom->zName);
}
}
}
#endif
/* Drop and reload the internal table schema. */
reloadTableSchema(pParse, pTab, zName);
exit_rename_table:
sqlite3SrcListDelete(db, pSrc);
sqlite3DbFree(db, zName);
db->flags = savedDbFlags;
}
/*
** The parser calls this routine after the CREATE VIRTUAL TABLE statement
** has been completely parsed.
*/
void sqlite3VtabFinishParse(Parse *pParse, Token *pEnd){
Table *pTab = pParse->pNewTable; /* The table being constructed */
sqlite3 *db = pParse->db; /* The database connection */
if( pTab==0 ) return;
addArgumentToVtab(pParse);
pParse->sArg.z = 0;
if( pTab->nModuleArg<1 ) return;
/* If the CREATE VIRTUAL TABLE statement is being entered for the
** first time (in other words if the virtual table is actually being
** created now instead of just being read out of sqlite_master) then
** do additional initialization work and store the statement text
** in the sqlite_master table.
*/
if( !db->init.busy ){
char *zStmt;
char *zWhere;
int iDb;
Vdbe *v;
/* Compute the complete text of the CREATE VIRTUAL TABLE statement */
if( pEnd ){
pParse->sNameToken.n = (int)(pEnd->z - pParse->sNameToken.z) + pEnd->n;
}
zStmt = sqlite3MPrintf(db, "CREATE VIRTUAL TABLE %T", &pParse->sNameToken);
/* A slot for the record has already been allocated in the
** SQLITE_MASTER table. We just need to update that slot with all
** the information we've collected.
**
** The VM register number pParse->regRowid holds the rowid of an
** entry in the sqlite_master table tht was created for this vtab
** by sqlite3StartTable().
*/
iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
sqlite3NestedParse(pParse,
"UPDATE %Q.%s "
"SET type='table', name=%Q, tbl_name=%Q, rootpage=0, sql=%Q "
"WHERE rowid=#%d",
db->aDb[iDb].zName, SCHEMA_TABLE(iDb),
pTab->zName,
pTab->zName,
zStmt,
pParse->regRowid
);
sqlite3DbFree(db, zStmt);
v = sqlite3GetVdbe(pParse);
sqlite3ChangeCookie(pParse, iDb);
sqlite3VdbeAddOp2(v, OP_Expire, 0, 0);
zWhere = sqlite3MPrintf(db, "name='%q'", pTab->zName);
sqlite3VdbeAddOp4(v, OP_ParseSchema, iDb, 1, 0, zWhere, P4_DYNAMIC);
sqlite3VdbeAddOp4(v, OP_VCreate, iDb, 0, 0,
pTab->zName, sqlite3Strlen30(pTab->zName) + 1);
}
/* If we are rereading the sqlite_master table create the in-memory
** record of the table. The xConnect() method is not called until
** the first time the virtual table is used in an SQL statement. This
** allows a schema that contains virtual tables to be loaded before
** the required virtual table implementations are registered. */
else {
Table *pOld;
Schema *pSchema = pTab->pSchema;
const char *zName = pTab->zName;
int nName = sqlite3Strlen30(zName);
pOld = sqlite3HashInsert(&pSchema->tblHash, zName, nName, pTab);
if( pOld ){
db->mallocFailed = 1;
assert( pTab==pOld ); /* Malloc must have failed inside HashInsert() */
return;
}
pSchema->db = pParse->db;
pParse->pNewTable = 0;
}
}
/*
** This routine is called after all of the trigger actions have been parsed
** in order to complete the process of building the trigger.
*/
void sqlite3FinishTrigger(
Parse *pParse, /* Parser context */
TriggerStep *pStepList, /* The triggered program */
Token *pAll /* Token that describes the complete CREATE TRIGGER */
){
Trigger *pTrig = pParse->pNewTrigger; /* Trigger being finished */
char *zName; /* Name of trigger */
sqlite3 *db = pParse->db; /* The database */
DbFixer sFix; /* Fixer object */
int iDb; /* Database containing the trigger */
Token nameToken; /* Trigger name for error reporting */
pParse->pNewTrigger = 0;
if (NEVER(pParse->nErr) || !pTrig) goto triggerfinish_cleanup;
zName = pTrig->zName;
iDb = sqlite3SchemaToIndex(pParse->db, pTrig->pSchema);
pTrig->step_list = pStepList;
while (pStepList){
pStepList->pTrig = pTrig;
pStepList = pStepList->pNext;
}
nameToken.z = pTrig->zName;
nameToken.n = sqlite3Strlen30(nameToken.z);
sqlite3FixInit(&sFix, pParse, iDb, "trigger", &nameToken);
if (sqlite3FixTriggerStep(&sFix, pTrig->step_list)
|| sqlite3FixExpr(&sFix, pTrig->pWhen)
){
goto triggerfinish_cleanup;
}
/* if we are not initializing,
** build the sqlite_master entry
*/
if (!db->init.busy){
Vdbe *v;
char *z;
/* Make an entry in the sqlite_master table */
v = sqlite3GetVdbe(pParse);
if (v == 0) goto triggerfinish_cleanup;
sqlite3BeginWriteOperation(pParse, 0, iDb);
z = sqlite3DbStrNDup(db, (char*)pAll->z, pAll->n);
sqlite3NestedParse(pParse,
"INSERT INTO %Q.%s VALUES('trigger',%Q,%Q,0,'CREATE TRIGGER %q')",
db->aDb[iDb].zName, SCHEMA_TABLE(iDb), zName,
pTrig->table, z);
sqlite3DbFree(db, z);
sqlite3ChangeCookie(pParse, iDb);
sqlite3VdbeAddParseSchemaOp(v, iDb,
sqlite3MPrintf(db, "type='trigger' AND name='%q'", zName));
}
if (db->init.busy){
Trigger *pLink = pTrig;
Hash *pHash = &db->aDb[iDb].pSchema->trigHash;
assert(sqlite3SchemaMutexHeld(db, iDb, 0));
pTrig = sqlite3HashInsert(pHash, zName, sqlite3Strlen30(zName), pTrig);
if (pTrig){
db->mallocFailed = 1;
}
else if (pLink->pSchema == pLink->pTabSchema){
Table *pTab;
int n = sqlite3Strlen30(pLink->table);
pTab = sqlite3HashFind(&pLink->pTabSchema->tblHash, pLink->table, n);
assert(pTab != 0);
pLink->pNext = pTab->pTrigger;
pTab->pTrigger = pLink;
}
}
triggerfinish_cleanup:
sqlite3DeleteTrigger(db, pTrig);
assert(!pParse->pNewTrigger);
sqlite3DeleteTriggerStep(db, pStepList);
}
/*
** Process an UPDATE statement.
**
** UPDATE OR IGNORE table_wxyz SET a=b, c=d WHERE e<5 AND f NOT NULL;
** \_______/ \________/ \______/ \________________/
* onError pTabList pChanges pWhere
*/
void sqlite3Update(
Parse *pParse, /* The parser context */
SrcList *pTabList, /* The table in which we should change things */
ExprList *pChanges, /* Things to be changed */
Expr *pWhere, /* The WHERE clause. May be null */
int onError /* How to handle constraint errors */
){
int i, j; /* Loop counters */
Table *pTab; /* The table to be updated */
int addr = 0; /* VDBE instruction address of the start of the loop */
WhereInfo *pWInfo; /* Information about the WHERE clause */
Vdbe *v; /* The virtual database engine */
Index *pIdx; /* For looping over indices */
int nIdx; /* Number of indices that need updating */
int nIdxTotal; /* Total number of indices */
int iCur; /* VDBE Cursor number of pTab */
sqlite3 *db; /* The database structure */
Index **apIdx = 0; /* An array of indices that need updating too */
char *aIdxUsed = 0; /* aIdxUsed[i]==1 if the i-th index is used */
int *aXRef = 0; /* aXRef[i] is the index in pChanges->a[] of the
** an expression for the i-th column of the table.
** aXRef[i]==-1 if the i-th column is not changed. */
int chngRowid; /* True if the record number is being changed */
Expr *pRowidExpr = 0; /* Expression defining the new record number */
int openAll = 0; /* True if all indices need to be opened */
AuthContext sContext; /* The authorization context */
NameContext sNC; /* The name-context to resolve expressions in */
int iDb; /* Database containing the table being updated */
int memCnt = 0; /* Memory cell used for counting rows changed */
int mem1; /* Memory address storing the rowid for next row to update */
#ifndef SQLITE_OMIT_TRIGGER
int isView; /* Trying to update a view */
int triggers_exist = 0; /* True if any row triggers exist */
#endif
int newIdx = -1; /* index of trigger "new" temp table */
int oldIdx = -1; /* index of trigger "old" temp table */
sContext.pParse = 0;
db = pParse->db;
if( pParse->nErr || db->mallocFailed ){
goto update_cleanup;
}
assert( pTabList->nSrc==1 );
/* Locate the table which we want to update.
*/
pTab = sqlite3SrcListLookup(pParse, pTabList);
if( pTab==0 ) goto update_cleanup;
iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
/* Figure out if we have any triggers and if the table being
** updated is a view
*/
#ifndef SQLITE_OMIT_TRIGGER
triggers_exist = sqlite3TriggersExist(pParse, pTab, TK_UPDATE, pChanges);
isView = pTab->pSelect!=0;
#else
# define triggers_exist 0
# define isView 0
#endif
#ifdef SQLITE_OMIT_VIEW
# undef isView
# define isView 0
#endif
if( sqlite3IsReadOnly(pParse, pTab, triggers_exist) ){
goto update_cleanup;
}
if( sqlite3ViewGetColumnNames(pParse, pTab) ){
goto update_cleanup;
}
aXRef = (int*)sqlite3DbMallocRaw(db, sizeof(int) * pTab->nCol );
if( aXRef==0 ) goto update_cleanup;
for(i=0; i<pTab->nCol; i++) aXRef[i] = -1;
/* If there are FOR EACH ROW triggers, allocate cursors for the
** special OLD and NEW tables
*/
if( triggers_exist ){
newIdx = pParse->nTab++;
oldIdx = pParse->nTab++;
}
/* Allocate a cursors for the main database table and for all indices.
** The index cursors might not be used, but if they are used they
** need to occur right after the database cursor. So go ahead and
** allocate enough space, just in case.
*/
pTabList->a[0].iCursor = iCur = pParse->nTab++;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
pParse->nTab++;
}
/* Initialize the name-context */
memset(&sNC, 0, sizeof(sNC));
sNC.pParse = pParse;
sNC.pSrcList = pTabList;
/* Resolve the column names in all the expressions of the
** of the UPDATE statement. Also find the column index
** for each column to be updated in the pChanges array. For each
** column to be updated, make sure we have authorization to change
** that column.
*/
chngRowid = 0;
for(i=0; i<pChanges->nExpr; i++){
if( sqlite3ExprResolveNames(&sNC, pChanges->a[i].pExpr) ){
goto update_cleanup;
}
for(j=0; j<pTab->nCol; j++){
if( sqlite3StrICmp(pTab->aCol[j].zName, pChanges->a[i].zName)==0 ){
if( j==pTab->iPKey ){
chngRowid = 1;
pRowidExpr = pChanges->a[i].pExpr;
}
aXRef[j] = i;
break;
}
}
if( j>=pTab->nCol ){
if( sqlite3IsRowid(pChanges->a[i].zName) ){
chngRowid = 1;
pRowidExpr = pChanges->a[i].pExpr;
}else{
sqlite3ErrorMsg(pParse, "no such column: %s", pChanges->a[i].zName);
goto update_cleanup;
}
}
#ifndef SQLITE_OMIT_AUTHORIZATION
{
int rc;
rc = sqlite3AuthCheck(pParse, SQLITE_UPDATE, pTab->zName,
pTab->aCol[j].zName, db->aDb[iDb].zName);
if( rc==SQLITE_DENY ){
goto update_cleanup;
}else if( rc==SQLITE_IGNORE ){
aXRef[j] = -1;
}
}
#endif
}
/* Allocate memory for the array apIdx[] and fill it with pointers to every
** index that needs to be updated. Indices only need updating if their
** key includes one of the columns named in pChanges or if the record
** number of the original table entry is changing.
*/
for(nIdx=nIdxTotal=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdxTotal++){
if( chngRowid ){
i = 0;
}else {
for(i=0; i<pIdx->nColumn; i++){
if( aXRef[pIdx->aiColumn[i]]>=0 ) break;
}
}
if( i<pIdx->nColumn ) nIdx++;
}
if( nIdxTotal>0 ){
apIdx = (Index**)sqlite3DbMallocRaw(db, sizeof(Index*) * nIdx + nIdxTotal );
if( apIdx==0 ) goto update_cleanup;
aIdxUsed = (char*)&apIdx[nIdx];
}
for(nIdx=j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
if( chngRowid ){
i = 0;
}else{
for(i=0; i<pIdx->nColumn; i++){
if( aXRef[pIdx->aiColumn[i]]>=0 ) break;
}
}
if( i<pIdx->nColumn ){
apIdx[nIdx++] = pIdx;
aIdxUsed[j] = 1;
}else{
aIdxUsed[j] = 0;
}
}
/* Begin generating code.
*/
v = sqlite3GetVdbe(pParse);
if( v==0 ) goto update_cleanup;
if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
sqlite3BeginWriteOperation(pParse, 1, iDb);
mem1 = pParse->nMem++;
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Virtual tables must be handled separately */
if( IsVirtual(pTab) ){
updateVirtualTable(pParse, pTabList, pTab, pChanges, pRowidExpr, aXRef,
pWhere);
pWhere = 0;
pTabList = 0;
goto update_cleanup;
}
#endif
/* Resolve the column names in all the expressions in the
** WHERE clause.
*/
if( sqlite3ExprResolveNames(&sNC, pWhere) ){
goto update_cleanup;
}
/* Start the view context
*/
if( isView ){
sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
}
/* If we are trying to update a view, realize that view into
** a ephemeral table.
*/
if( isView ){
Select *pView;
pView = sqlite3SelectDup(db, pTab->pSelect);
sqlite3Select(pParse, pView, SRT_EphemTab, iCur, 0, 0, 0, 0);
sqlite3SelectDelete(pView);
}
/* Begin the database scan
*/
pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0);
if( pWInfo==0 ) goto update_cleanup;
/* Remember the rowid of every item to be updated.
*/
sqlite3VdbeAddOp(v, IsVirtual(pTab) ? OP_VRowid : OP_Rowid, iCur, 0);
sqlite3VdbeAddOp(v, OP_FifoWrite, 0, 0);
/* End the database scan loop.
*/
sqlite3WhereEnd(pWInfo);
/* Initialize the count of updated rows
*/
if( db->flags & SQLITE_CountRows && !pParse->trigStack ){
memCnt = pParse->nMem++;
sqlite3VdbeAddOp(v, OP_MemInt, 0, memCnt);
}
if( triggers_exist ){
/* Create pseudo-tables for NEW and OLD
*/
sqlite3VdbeAddOp(v, OP_OpenPseudo, oldIdx, 0);
sqlite3VdbeAddOp(v, OP_SetNumColumns, oldIdx, pTab->nCol);
sqlite3VdbeAddOp(v, OP_OpenPseudo, newIdx, 0);
sqlite3VdbeAddOp(v, OP_SetNumColumns, newIdx, pTab->nCol);
/* The top of the update loop for when there are triggers.
*/
addr = sqlite3VdbeAddOp(v, OP_FifoRead, 0, 0);
sqlite3VdbeAddOp(v, OP_StackDepth, -1, 0);
sqlite3VdbeAddOp(v, OP_MemStore, mem1, 0);
if( !isView ){
/* Open a cursor and make it point to the record that is
** being updated.
*/
sqlite3OpenTable(pParse, iCur, iDb, pTab, OP_OpenRead);
}
sqlite3VdbeAddOp(v, OP_NotExists, iCur, addr);
/* Generate the OLD table
*/
sqlite3VdbeAddOp(v, OP_Rowid, iCur, 0);
sqlite3VdbeAddOp(v, OP_RowData, iCur, 0);
sqlite3VdbeAddOp(v, OP_Insert, oldIdx, 0);
/* Generate the NEW table
*/
if( chngRowid ){
sqlite3ExprCodeAndCache(pParse, pRowidExpr);
}else{
sqlite3VdbeAddOp(v, OP_Rowid, iCur, 0);
}
for(i=0; i<pTab->nCol; i++){
if( i==pTab->iPKey ){
sqlite3VdbeAddOp(v, OP_Null, 0, 0);
continue;
}
j = aXRef[i];
if( j<0 ){
sqlite3VdbeAddOp(v, OP_Column, iCur, i);
sqlite3ColumnDefault(v, pTab, i);
}else{
sqlite3ExprCodeAndCache(pParse, pChanges->a[j].pExpr);
}
}
sqlite3VdbeAddOp(v, OP_MakeRecord, pTab->nCol, 0);
if( !isView ){
sqlite3TableAffinityStr(v, pTab);
}
if( pParse->nErr ) goto update_cleanup;
sqlite3VdbeAddOp(v, OP_Insert, newIdx, 0);
if( !isView ){
sqlite3VdbeAddOp(v, OP_Close, iCur, 0);
}
/* Fire the BEFORE and INSTEAD OF triggers
*/
if( sqlite3CodeRowTrigger(pParse, TK_UPDATE, pChanges, TRIGGER_BEFORE, pTab,
newIdx, oldIdx, onError, addr) ){
goto update_cleanup;
}
if( !isView ){
sqlite3VdbeAddOp(v, OP_MemLoad, mem1, 0);
}
}
if( !isView && !IsVirtual(pTab) ){
/*
** Open every index that needs updating. Note that if any
** index could potentially invoke a REPLACE conflict resolution
** action, then we need to open all indices because we might need
** to be deleting some records.
*/
sqlite3OpenTable(pParse, iCur, iDb, pTab, OP_OpenWrite);
if( onError==OE_Replace ){
openAll = 1;
}else{
openAll = 0;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
if( pIdx->onError==OE_Replace ){
openAll = 1;
break;
}
}
}
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aIdxUsed[i] ){
KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);
sqlite3VdbeAddOp(v, OP_Integer, iDb, 0);
sqlite3VdbeOp3(v, OP_OpenWrite, iCur+i+1, pIdx->tnum,
(char*)pKey, P3_KEYINFO_HANDOFF);
assert( pParse->nTab>iCur+i+1 );
}
}
/* Loop over every record that needs updating. We have to load
** the old data for each record to be updated because some columns
** might not change and we will need to copy the old value.
** Also, the old data is needed to delete the old index entries.
** So make the cursor point at the old record.
*/
if( !triggers_exist ){
addr = sqlite3VdbeAddOp(v, OP_FifoRead, 0, 0);
sqlite3VdbeAddOp(v, OP_StackDepth, -1, 0);
sqlite3VdbeAddOp(v, OP_MemStore, mem1, 0);
}
sqlite3VdbeAddOp(v, OP_NotExists, iCur, addr);
sqlite3VdbeAddOp(v, OP_MemLoad, mem1, 0);
/* If the record number will change, push the record number as it
** will be after the update. (The old record number is currently
** on top of the stack.)
*/
if( chngRowid ){
sqlite3ExprCode(pParse, pRowidExpr);
sqlite3VdbeAddOp(v, OP_MustBeInt, 0, 0);
}
/* Compute new data for this record.
*/
for(i=0; i<pTab->nCol; i++){
if( i==pTab->iPKey ){
sqlite3VdbeAddOp(v, OP_Null, 0, 0);
continue;
}
j = aXRef[i];
if( j<0 ){
sqlite3VdbeAddOp(v, OP_Column, iCur, i);
sqlite3ColumnDefault(v, pTab, i);
}else{
sqlite3ExprCode(pParse, pChanges->a[j].pExpr);
}
}
/* Do constraint checks
*/
sqlite3GenerateConstraintChecks(pParse, pTab, iCur, aIdxUsed, chngRowid, 1,
onError, addr);
/* Delete the old indices for the current record.
*/
sqlite3GenerateRowIndexDelete(v, pTab, iCur, aIdxUsed);
/* If changing the record number, delete the old record.
*/
if( chngRowid ){
sqlite3VdbeAddOp(v, OP_Delete, iCur, 0);
}
/* Create the new index entries and the new record.
*/
sqlite3CompleteInsertion(pParse, pTab, iCur, aIdxUsed, chngRowid, 1, -1, 0);
}
/* Increment the row counter
*/
if( db->flags & SQLITE_CountRows && !pParse->trigStack){
sqlite3VdbeAddOp(v, OP_MemIncr, 1, memCnt);
}
/* If there are triggers, close all the cursors after each iteration
** through the loop. The fire the after triggers.
*/
if( triggers_exist ){
if( !isView ){
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aIdxUsed[i] )
sqlite3VdbeAddOp(v, OP_Close, iCur+i+1, 0);
}
sqlite3VdbeAddOp(v, OP_Close, iCur, 0);
}
if( sqlite3CodeRowTrigger(pParse, TK_UPDATE, pChanges, TRIGGER_AFTER, pTab,
newIdx, oldIdx, onError, addr) ){
goto update_cleanup;
}
}
/* Repeat the above with the next record to be updated, until
** all record selected by the WHERE clause have been updated.
*/
sqlite3VdbeAddOp(v, OP_Goto, 0, addr);
sqlite3VdbeJumpHere(v, addr);
/* Close all tables if there were no FOR EACH ROW triggers */
if( !triggers_exist ){
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aIdxUsed[i] ){
sqlite3VdbeAddOp(v, OP_Close, iCur+i+1, 0);
}
}
sqlite3VdbeAddOp(v, OP_Close, iCur, 0);
}else{
sqlite3VdbeAddOp(v, OP_Close, newIdx, 0);
sqlite3VdbeAddOp(v, OP_Close, oldIdx, 0);
}
/*
** Return the number of rows that were changed. If this routine is
** generating code because of a call to sqlite3NestedParse(), do not
** invoke the callback function.
*/
if( db->flags & SQLITE_CountRows && !pParse->trigStack && pParse->nested==0 ){
sqlite3VdbeAddOp(v, OP_MemLoad, memCnt, 0);
sqlite3VdbeAddOp(v, OP_Callback, 1, 0);
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows updated", P3_STATIC);
}
update_cleanup:
sqlite3AuthContextPop(&sContext);
sqlite3_free(apIdx);
sqlite3_free(aXRef);
sqlite3SrcListDelete(pTabList);
sqlite3ExprListDelete(pChanges);
sqlite3ExprDelete(pWhere);
return;
}
/*
** Generate code to do an analysis of all indices associated with
** a single table.
*/
static void analyzeOneTable(
Parse *pParse, /* Parser context */
Table *pTab, /* Table whose indices are to be analyzed */
int iStatCur, /* Index of VdbeCursor that writes the sqlite_stat1 table */
int iMem /* Available memory locations begin here */
){
sqlite3 *db = pParse->db; /* Database handle */
Index *pIdx; /* An index to being analyzed */
int iIdxCur; /* Cursor open on index being analyzed */
Vdbe *v; /* The virtual machine being built up */
int i; /* Loop counter */
int topOfLoop; /* The top of the loop */
int endOfLoop; /* The end of the loop */
int addr = 0; /* The address of an instruction */
int jZeroRows = 0; /* Jump from here if number of rows is zero */
int iDb; /* Index of database containing pTab */
int regTabname = iMem++; /* Register containing table name */
int regIdxname = iMem++; /* Register containing index name */
int regSampleno = iMem++; /* Register containing next sample number */
int regCol = iMem++; /* Content of a column analyzed table */
int regRec = iMem++; /* Register holding completed record */
int regTemp = iMem++; /* Temporary use register */
int regRowid = iMem++; /* Rowid for the inserted record */
#ifdef SQLITE_ENABLE_STAT2
int regTemp2 = iMem++; /* Temporary use register */
int regSamplerecno = iMem++; /* Index of next sample to record */
int regRecno = iMem++; /* Current sample index */
int regLast = iMem++; /* Index of last sample to record */
int regFirst = iMem++; /* Index of first sample to record */
#endif
v = sqlite3GetVdbe(pParse);
if( v==0 || NEVER(pTab==0) ){
return;
}
if( pTab->tnum==0 ){
/* Do not gather statistics on views or virtual tables */
return;
}
if( memcmp(pTab->zName, "sqlite_", 7)==0 ){
/* Do not gather statistics on system tables */
return;
}
assert( sqlite3BtreeHoldsAllMutexes(db) );
iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
assert( iDb>=0 );
#ifndef SQLITE_OMIT_AUTHORIZATION
if( sqlite3AuthCheck(pParse, SQLITE_ANALYZE, pTab->zName, 0,
db->aDb[iDb].zName ) ){
return;
}
#endif
/* Establish a read-lock on the table at the shared-cache level. */
sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);
iIdxCur = pParse->nTab++;
sqlite3VdbeAddOp4(v, OP_String8, 0, regTabname, 0, pTab->zName, 0);
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
int nCol = pIdx->nColumn;
KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);
if( iMem+1+(nCol*2)>pParse->nMem ){
pParse->nMem = iMem+1+(nCol*2);
}
/* Open a cursor to the index to be analyzed. */
assert( iDb==sqlite3SchemaToIndex(db, pIdx->pSchema) );
sqlite3VdbeAddOp4(v, OP_OpenRead, iIdxCur, pIdx->tnum, iDb,
(char *)pKey, P4_KEYINFO_HANDOFF);
VdbeComment((v, "%s", pIdx->zName));
/* Populate the register containing the index name. */
sqlite3VdbeAddOp4(v, OP_String8, 0, regIdxname, 0, pIdx->zName, 0);
#ifdef SQLITE_ENABLE_STAT2
/* If this iteration of the loop is generating code to analyze the
** first index in the pTab->pIndex list, then register regLast has
** not been populated. In this case populate it now. */
if( pTab->pIndex==pIdx ){
sqlite3VdbeAddOp2(v, OP_Integer, SQLITE_INDEX_SAMPLES, regSamplerecno);
sqlite3VdbeAddOp2(v, OP_Integer, SQLITE_INDEX_SAMPLES*2-1, regTemp);
sqlite3VdbeAddOp2(v, OP_Integer, SQLITE_INDEX_SAMPLES*2, regTemp2);
sqlite3VdbeAddOp2(v, OP_Count, iIdxCur, regLast);
sqlite3VdbeAddOp2(v, OP_Null, 0, regFirst);
addr = sqlite3VdbeAddOp3(v, OP_Lt, regSamplerecno, 0, regLast);
sqlite3VdbeAddOp3(v, OP_Divide, regTemp2, regLast, regFirst);
sqlite3VdbeAddOp3(v, OP_Multiply, regLast, regTemp, regLast);
sqlite3VdbeAddOp2(v, OP_AddImm, regLast, SQLITE_INDEX_SAMPLES*2-2);
sqlite3VdbeAddOp3(v, OP_Divide, regTemp2, regLast, regLast);
sqlite3VdbeJumpHere(v, addr);
}
/* Zero the regSampleno and regRecno registers. */
sqlite3VdbeAddOp2(v, OP_Integer, 0, regSampleno);
sqlite3VdbeAddOp2(v, OP_Integer, 0, regRecno);
sqlite3VdbeAddOp2(v, OP_Copy, regFirst, regSamplerecno);
#endif
/* The block of memory cells initialized here is used as follows.
**
** iMem:
** The total number of rows in the table.
**
** iMem+1 .. iMem+nCol:
** Number of distinct entries in index considering the
** left-most N columns only, where N is between 1 and nCol,
** inclusive.
**
** iMem+nCol+1 .. Mem+2*nCol:
** Previous value of indexed columns, from left to right.
**
** Cells iMem through iMem+nCol are initialized to 0. The others are
** initialized to contain an SQL NULL.
*/
for(i=0; i<=nCol; i++){
sqlite3VdbeAddOp2(v, OP_Integer, 0, iMem+i);
}
for(i=0; i<nCol; i++){
sqlite3VdbeAddOp2(v, OP_Null, 0, iMem+nCol+i+1);
}
/* Start the analysis loop. This loop runs through all the entries in
** the index b-tree. */
endOfLoop = sqlite3VdbeMakeLabel(v);
sqlite3VdbeAddOp2(v, OP_Rewind, iIdxCur, endOfLoop);
topOfLoop = sqlite3VdbeCurrentAddr(v);
sqlite3VdbeAddOp2(v, OP_AddImm, iMem, 1);
for(i=0; i<nCol; i++){
sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, i, regCol);
#ifdef SQLITE_ENABLE_STAT2
if( i==0 ){
/* Check if the record that cursor iIdxCur points to contains a
** value that should be stored in the sqlite_stat2 table. If so,
** store it. */
int ne = sqlite3VdbeAddOp3(v, OP_Ne, regRecno, 0, regSamplerecno);
assert( regTabname+1==regIdxname
&& regTabname+2==regSampleno
&& regTabname+3==regCol
);
sqlite3VdbeChangeP5(v, SQLITE_JUMPIFNULL);
sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 4, regRec, "aaab", 0);
sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur+1, regRowid);
sqlite3VdbeAddOp3(v, OP_Insert, iStatCur+1, regRec, regRowid);
/* Calculate new values for regSamplerecno and regSampleno.
**
** sampleno = sampleno + 1
** samplerecno = samplerecno+(remaining records)/(remaining samples)
*/
sqlite3VdbeAddOp2(v, OP_AddImm, regSampleno, 1);
sqlite3VdbeAddOp3(v, OP_Subtract, regRecno, regLast, regTemp);
sqlite3VdbeAddOp2(v, OP_AddImm, regTemp, -1);
sqlite3VdbeAddOp2(v, OP_Integer, SQLITE_INDEX_SAMPLES, regTemp2);
sqlite3VdbeAddOp3(v, OP_Subtract, regSampleno, regTemp2, regTemp2);
sqlite3VdbeAddOp3(v, OP_Divide, regTemp2, regTemp, regTemp);
sqlite3VdbeAddOp3(v, OP_Add, regSamplerecno, regTemp, regSamplerecno);
sqlite3VdbeJumpHere(v, ne);
sqlite3VdbeAddOp2(v, OP_AddImm, regRecno, 1);
}
#endif
sqlite3VdbeAddOp3(v, OP_Ne, regCol, 0, iMem+nCol+i+1);
/**** TODO: add collating sequence *****/
sqlite3VdbeChangeP5(v, SQLITE_JUMPIFNULL);
}
if( db->mallocFailed ){
/* If a malloc failure has occurred, then the result of the expression
** passed as the second argument to the call to sqlite3VdbeJumpHere()
** below may be negative. Which causes an assert() to fail (or an
** out-of-bounds write if SQLITE_DEBUG is not defined). */
return;
}
sqlite3VdbeAddOp2(v, OP_Goto, 0, endOfLoop);
for(i=0; i<nCol; i++){
sqlite3VdbeJumpHere(v, sqlite3VdbeCurrentAddr(v)-(nCol*2));
sqlite3VdbeAddOp2(v, OP_AddImm, iMem+i+1, 1);
sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, i, iMem+nCol+i+1);
}
/* End of the analysis loop. */
sqlite3VdbeResolveLabel(v, endOfLoop);
sqlite3VdbeAddOp2(v, OP_Next, iIdxCur, topOfLoop);
sqlite3VdbeAddOp1(v, OP_Close, iIdxCur);
/* Store the results in sqlite_stat1.
**
** The result is a single row of the sqlite_stat1 table. The first
** two columns are the names of the table and index. The third column
** is a string composed of a list of integer statistics about the
** index. The first integer in the list is the total number of entries
** in the index. There is one additional integer in the list for each
** column of the table. This additional integer is a guess of how many
** rows of the table the index will select. If D is the count of distinct
** values and K is the total number of rows, then the integer is computed
** as:
**
** I = (K+D-1)/D
**
** If K==0 then no entry is made into the sqlite_stat1 table.
** If K>0 then it is always the case the D>0 so division by zero
** is never possible.
*/
sqlite3VdbeAddOp2(v, OP_SCopy, iMem, regSampleno);
if( jZeroRows==0 ){
jZeroRows = sqlite3VdbeAddOp1(v, OP_IfNot, iMem);
}
for(i=0; i<nCol; i++){
sqlite3VdbeAddOp4(v, OP_String8, 0, regTemp, 0, " ", 0);
sqlite3VdbeAddOp3(v, OP_Concat, regTemp, regSampleno, regSampleno);
sqlite3VdbeAddOp3(v, OP_Add, iMem, iMem+i+1, regTemp);
sqlite3VdbeAddOp2(v, OP_AddImm, regTemp, -1);
sqlite3VdbeAddOp3(v, OP_Divide, iMem+i+1, regTemp, regTemp);
sqlite3VdbeAddOp1(v, OP_ToInt, regTemp);
sqlite3VdbeAddOp3(v, OP_Concat, regTemp, regSampleno, regSampleno);
}
sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 3, regRec, "aaa", 0);
sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur, regRowid);
sqlite3VdbeAddOp3(v, OP_Insert, iStatCur, regRec, regRowid);
sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
}
/* If the table has no indices, create a single sqlite_stat1 entry
** containing NULL as the index name and the row count as the content.
*/
if( pTab->pIndex==0 ){
sqlite3VdbeAddOp3(v, OP_OpenRead, iIdxCur, pTab->tnum, iDb);
VdbeComment((v, "%s", pTab->zName));
sqlite3VdbeAddOp2(v, OP_Count, iIdxCur, regSampleno);
sqlite3VdbeAddOp1(v, OP_Close, iIdxCur);
}else{
assert( jZeroRows>0 );
addr = sqlite3VdbeAddOp0(v, OP_Goto);
sqlite3VdbeJumpHere(v, jZeroRows);
}
sqlite3VdbeAddOp2(v, OP_Null, 0, regIdxname);
sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 3, regRec, "aaa", 0);
sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur, regRowid);
sqlite3VdbeAddOp3(v, OP_Insert, iStatCur, regRec, regRowid);
sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
if( pParse->nMem<regRec ) pParse->nMem = regRec;
if( jZeroRows ){
sqlite3VdbeJumpHere(v, addr);
}
}
/*
** Open a blob handle.
*/
int sqlite3_blob_open(
sqlite3* db, /* The database connection */
const char *zDb, /* The attached database containing the blob */
const char *zTable, /* The table containing the blob */
const char *zColumn, /* The column containing the blob */
sqlite_int64 iRow, /* The row containing the glob */
int flags, /* True -> read/write access, false -> read-only */
sqlite3_blob **ppBlob /* Handle for accessing the blob returned here */
){
int nAttempt = 0;
int iCol; /* Index of zColumn in row-record */
/* This VDBE program seeks a btree cursor to the identified
** db/table/row entry. The reason for using a vdbe program instead
** of writing code to use the b-tree layer directly is that the
** vdbe program will take advantage of the various transaction,
** locking and error handling infrastructure built into the vdbe.
**
** After seeking the cursor, the vdbe executes an OP_ResultRow.
** Code external to the Vdbe then "borrows" the b-tree cursor and
** uses it to implement the blob_read(), blob_write() and
** blob_bytes() functions.
**
** The sqlite3_blob_close() function finalizes the vdbe program,
** which closes the b-tree cursor and (possibly) commits the
** transaction.
*/
static const int iLn = VDBE_OFFSET_LINENO(4);
static const VdbeOpList openBlob[] = {
/* {OP_Transaction, 0, 0, 0}, // 0: Inserted separately */
{OP_TableLock, 0, 0, 0}, /* 1: Acquire a read or write lock */
/* One of the following two instructions is replaced by an OP_Noop. */
{OP_OpenRead, 0, 0, 0}, /* 2: Open cursor 0 for reading */
{OP_OpenWrite, 0, 0, 0}, /* 3: Open cursor 0 for read/write */
{OP_Variable, 1, 1, 1}, /* 4: Push the rowid to the stack */
{OP_NotExists, 0, 10, 1}, /* 5: Seek the cursor */
{OP_Column, 0, 0, 1}, /* 6 */
{OP_ResultRow, 1, 0, 0}, /* 7 */
{OP_Goto, 0, 4, 0}, /* 8 */
{OP_Close, 0, 0, 0}, /* 9 */
{OP_Halt, 0, 0, 0}, /* 10 */
};
int rc = SQLITE_OK;
char *zErr = 0;
Table *pTab;
Parse *pParse = 0;
Incrblob *pBlob = 0;
#ifdef SQLITE_ENABLE_API_ARMOR
if( !sqlite3SafetyCheckOk(db) || ppBlob==0 || zTable==0 ){
return SQLITE_MISUSE_BKPT;
}
#endif
flags = !!flags; /* flags = (flags ? 1 : 0); */
*ppBlob = 0;
sqlite3_mutex_enter(db->mutex);
pBlob = (Incrblob *)sqlite3DbMallocZero(db, sizeof(Incrblob));
if( !pBlob ) goto blob_open_out;
pParse = sqlite3StackAllocRaw(db, sizeof(*pParse));
if( !pParse ) goto blob_open_out;
do {
memset(pParse, 0, sizeof(Parse));
pParse->db = db;
sqlite3DbFree(db, zErr);
zErr = 0;
sqlite3BtreeEnterAll(db);
pTab = sqlite3LocateTable(pParse, 0, zTable, zDb);
if( pTab && IsVirtual(pTab) ){
pTab = 0;
sqlite3ErrorMsg(pParse, "cannot open virtual table: %s", zTable);
}
if( pTab && !HasRowid(pTab) ){
pTab = 0;
sqlite3ErrorMsg(pParse, "cannot open table without rowid: %s", zTable);
}
#ifndef SQLITE_OMIT_VIEW
if( pTab && pTab->pSelect ){
pTab = 0;
sqlite3ErrorMsg(pParse, "cannot open view: %s", zTable);
}
#endif
if( !pTab ){
if( pParse->zErrMsg ){
sqlite3DbFree(db, zErr);
zErr = pParse->zErrMsg;
pParse->zErrMsg = 0;
}
rc = SQLITE_ERROR;
sqlite3BtreeLeaveAll(db);
goto blob_open_out;
}
/* Now search pTab for the exact column. */
for(iCol=0; iCol<pTab->nCol; iCol++) {
if( sqlite3StrICmp(pTab->aCol[iCol].zName, zColumn)==0 ){
break;
}
}
if( iCol==pTab->nCol ){
sqlite3DbFree(db, zErr);
zErr = sqlite3MPrintf(db, "no such column: \"%s\"", zColumn);
rc = SQLITE_ERROR;
sqlite3BtreeLeaveAll(db);
goto blob_open_out;
}
/* If the value is being opened for writing, check that the
** column is not indexed, and that it is not part of a foreign key.
** It is against the rules to open a column to which either of these
** descriptions applies for writing. */
if( flags ){
const char *zFault = 0;
Index *pIdx;
#ifndef SQLITE_OMIT_FOREIGN_KEY
if( db->flags&SQLITE_ForeignKeys ){
/* Check that the column is not part of an FK child key definition. It
** is not necessary to check if it is part of a parent key, as parent
** key columns must be indexed. The check below will pick up this
** case. */
FKey *pFKey;
for(pFKey=pTab->pFKey; pFKey; pFKey=pFKey->pNextFrom){
int j;
for(j=0; j<pFKey->nCol; j++){
if( pFKey->aCol[j].iFrom==iCol ){
zFault = "foreign key";
}
}
}
}
#endif
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
int j;
for(j=0; j<pIdx->nKeyCol; j++){
if( pIdx->aiColumn[j]==iCol ){
zFault = "indexed";
}
}
}
if( zFault ){
sqlite3DbFree(db, zErr);
zErr = sqlite3MPrintf(db, "cannot open %s column for writing", zFault);
rc = SQLITE_ERROR;
sqlite3BtreeLeaveAll(db);
goto blob_open_out;
}
}
pBlob->pStmt = (sqlite3_stmt *)sqlite3VdbeCreate(pParse);
assert( pBlob->pStmt || db->mallocFailed );
if( pBlob->pStmt ){
Vdbe *v = (Vdbe *)pBlob->pStmt;
int iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
sqlite3VdbeAddOp4Int(v, OP_Transaction, iDb, flags,
pTab->pSchema->schema_cookie,
pTab->pSchema->iGeneration);
sqlite3VdbeChangeP5(v, 1);
sqlite3VdbeAddOpList(v, ArraySize(openBlob), openBlob, iLn);
/* Make sure a mutex is held on the table to be accessed */
sqlite3VdbeUsesBtree(v, iDb);
/* Configure the OP_TableLock instruction */
#ifdef SQLITE_OMIT_SHARED_CACHE
sqlite3VdbeChangeToNoop(v, 1);
#else
sqlite3VdbeChangeP1(v, 1, iDb);
sqlite3VdbeChangeP2(v, 1, pTab->tnum);
sqlite3VdbeChangeP3(v, 1, flags);
sqlite3VdbeChangeP4(v, 1, pTab->zName, P4_TRANSIENT);
#endif
/* Remove either the OP_OpenWrite or OpenRead. Set the P2
** parameter of the other to pTab->tnum. */
sqlite3VdbeChangeToNoop(v, 3 - flags);
sqlite3VdbeChangeP2(v, 2 + flags, pTab->tnum);
sqlite3VdbeChangeP3(v, 2 + flags, iDb);
/* Configure the number of columns. Configure the cursor to
** think that the table has one more column than it really
** does. An OP_Column to retrieve this imaginary column will
** always return an SQL NULL. This is useful because it means
** we can invoke OP_Column to fill in the vdbe cursors type
** and offset cache without causing any IO.
*/
sqlite3VdbeChangeP4(v, 2+flags, SQLITE_INT_TO_PTR(pTab->nCol+1),P4_INT32);
sqlite3VdbeChangeP2(v, 6, pTab->nCol);
if( !db->mallocFailed ){
pParse->nVar = 1;
pParse->nMem = 1;
pParse->nTab = 1;
sqlite3VdbeMakeReady(v, pParse);
}
}
pBlob->flags = flags;
pBlob->iCol = iCol;
pBlob->db = db;
sqlite3BtreeLeaveAll(db);
if( db->mallocFailed ){
goto blob_open_out;
}
sqlite3_bind_int64(pBlob->pStmt, 1, iRow);
rc = blobSeekToRow(pBlob, iRow, &zErr);
} while( (++nAttempt)<SQLITE_MAX_SCHEMA_RETRY && rc==SQLITE_SCHEMA );
blob_open_out:
if( rc==SQLITE_OK && db->mallocFailed==0 ){
*ppBlob = (sqlite3_blob *)pBlob;
}else{
if( pBlob && pBlob->pStmt ) sqlite3VdbeFinalize((Vdbe *)pBlob->pStmt);
sqlite3DbFree(db, pBlob);
}
sqlite3ErrorWithMsg(db, rc, (zErr ? "%s" : 0), zErr);
sqlite3DbFree(db, zErr);
sqlite3ParserReset(pParse);
sqlite3StackFree(db, pParse);
rc = sqlite3ApiExit(db, rc);
sqlite3_mutex_leave(db->mutex);
return rc;
}
/*
** This function is called by the parser after the table-name in
** an "ALTER TABLE <table-name> ADD" statement is parsed. Argument
** pSrc is the full-name of the table being altered.
**
** This routine makes a (partial) copy of the Table structure
** for the table being altered and sets Parse.pNewTable to point
** to it. Routines called by the parser as the column definition
** is parsed (i.e. sqlite3AddColumn()) add the new Column data to
** the copy. The copy of the Table structure is deleted by tokenize.c
** after parsing is finished.
**
** Routine sqlite3AlterFinishAddColumn() will be called to complete
** coding the "ALTER TABLE ... ADD" statement.
*/
void sqlite3AlterBeginAddColumn(Parse *pParse, SrcList *pSrc){
Table *pNew;
Table *pTab;
Vdbe *v;
int iDb;
int i;
int nAlloc;
/* Look up the table being altered. */
assert( pParse->pNewTable==0 );
if( sqlite3MallocFailed() ) goto exit_begin_add_column;
pTab = sqlite3LocateTable(pParse, pSrc->a[0].zName, pSrc->a[0].zDatabase);
if( !pTab ) goto exit_begin_add_column;
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( IsVirtual(pTab) ){
sqlite3ErrorMsg(pParse, "virtual tables may not be altered");
goto exit_begin_add_column;
}
#endif
/* Make sure this is not an attempt to ALTER a view. */
if( pTab->pSelect ){
sqlite3ErrorMsg(pParse, "Cannot add a column to a view");
goto exit_begin_add_column;
}
assert( pTab->addColOffset>0 );
iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
/* Put a copy of the Table struct in Parse.pNewTable for the
** sqlite3AddColumn() function and friends to modify.
*/
pNew = (Table *)sqliteMalloc(sizeof(Table));
if( !pNew ) goto exit_begin_add_column;
pParse->pNewTable = pNew;
pNew->nRef = 1;
pNew->nCol = pTab->nCol;
assert( pNew->nCol>0 );
nAlloc = (((pNew->nCol-1)/8)*8)+8;
assert( nAlloc>=pNew->nCol && nAlloc%8==0 && nAlloc-pNew->nCol<8 );
pNew->aCol = (Column *)sqliteMalloc(sizeof(Column)*nAlloc);
pNew->zName = sqliteStrDup(pTab->zName);
if( !pNew->aCol || !pNew->zName ){
goto exit_begin_add_column;
}
memcpy(pNew->aCol, pTab->aCol, sizeof(Column)*pNew->nCol);
for(i=0; i<pNew->nCol; i++){
Column *pCol = &pNew->aCol[i];
pCol->zName = sqliteStrDup(pCol->zName);
pCol->zColl = 0;
pCol->zType = 0;
pCol->pDflt = 0;
}
pNew->pSchema = pParse->db->aDb[iDb].pSchema;
pNew->addColOffset = pTab->addColOffset;
pNew->nRef = 1;
/* Begin a transaction and increment the schema cookie. */
sqlite3BeginWriteOperation(pParse, 0, iDb);
v = sqlite3GetVdbe(pParse);
if( !v ) goto exit_begin_add_column;
sqlite3ChangeCookie(pParse->db, v, iDb);
exit_begin_add_column:
sqlite3SrcListDelete(pSrc);
return;
}
/*
** This function is called after an "ALTER TABLE ... ADD" statement
** has been parsed. Argument pColDef contains the text of the new
** column definition.
**
** The Table structure pParse->pNewTable was extended to include
** the new column during parsing.
*/
void sqlite3AlterFinishAddColumn(Parse *pParse, Token *pColDef){
Table *pNew; /* Copy of pParse->pNewTable */
Table *pTab; /* Table being altered */
int iDb; /* Database number */
const char *zDb; /* Database name */
const char *zTab; /* Table name */
char *zCol; /* Null-terminated column definition */
Column *pCol; /* The new column */
Expr *pDflt; /* Default value for the new column */
if( pParse->nErr ) return;
pNew = pParse->pNewTable;
assert( pNew );
iDb = sqlite3SchemaToIndex(pParse->db, pNew->pSchema);
zDb = pParse->db->aDb[iDb].zName;
zTab = pNew->zName;
pCol = &pNew->aCol[pNew->nCol-1];
pDflt = pCol->pDflt;
pTab = sqlite3FindTable(pParse->db, zTab, zDb);
assert( pTab );
#ifndef SQLITE_OMIT_AUTHORIZATION
/* Invoke the authorization callback. */
if( sqlite3AuthCheck(pParse, SQLITE_ALTER_TABLE, zDb, pTab->zName, 0) ){
return;
}
#endif
/* If the default value for the new column was specified with a
** literal NULL, then set pDflt to 0. This simplifies checking
** for an SQL NULL default below.
*/
if( pDflt && pDflt->op==TK_NULL ){
pDflt = 0;
}
/* Check that the new column is not specified as PRIMARY KEY or UNIQUE.
** If there is a NOT NULL constraint, then the default value for the
** column must not be NULL.
*/
if( pCol->isPrimKey ){
sqlite3ErrorMsg(pParse, "Cannot add a PRIMARY KEY column");
return;
}
if( pNew->pIndex ){
sqlite3ErrorMsg(pParse, "Cannot add a UNIQUE column");
return;
}
if( pCol->notNull && !pDflt ){
sqlite3ErrorMsg(pParse,
"Cannot add a NOT NULL column with default value NULL");
return;
}
/* Ensure the default expression is something that sqlite3ValueFromExpr()
** can handle (i.e. not CURRENT_TIME etc.)
*/
if( pDflt ){
sqlite3_value *pVal;
if( sqlite3ValueFromExpr(pDflt, SQLITE_UTF8, SQLITE_AFF_NONE, &pVal) ){
/* malloc() has failed */
return;
}
if( !pVal ){
sqlite3ErrorMsg(pParse, "Cannot add a column with non-constant default");
return;
}
sqlite3ValueFree(pVal);
}
/* Modify the CREATE TABLE statement. */
zCol = sqliteStrNDup((char*)pColDef->z, pColDef->n);
if( zCol ){
char *zEnd = &zCol[pColDef->n-1];
while( (zEnd>zCol && *zEnd==';') || isspace(*(unsigned char *)zEnd) ){
*zEnd-- = '\0';
}
sqlite3NestedParse(pParse,
"UPDATE %Q.%s SET "
"sql = substr(sql,1,%d) || ', ' || %Q || substr(sql,%d,length(sql)) "
"WHERE type = 'table' AND name = %Q",
zDb, SCHEMA_TABLE(iDb), pNew->addColOffset, zCol, pNew->addColOffset+1,
zTab
);
sqliteFree(zCol);
}
/* If the default value of the new column is NULL, then set the file
** format to 2. If the default value of the new column is not NULL,
** the file format becomes 3.
*/
sqlite3MinimumFileFormat(pParse, iDb, pDflt ? 3 : 2);
/* Reload the schema of the modified table. */
reloadTableSchema(pParse, pTab, pTab->zName);
}
/*
** Generate code to implement the "ALTER TABLE xxx RENAME TO yyy"
** command.
*/
void sqlite3AlterRenameTable(
Parse *pParse, /* Parser context. */
SrcList *pSrc, /* The table to rename. */
Token *pName /* The new table name. */
){
int iDb; /* Database that contains the table */
char *zDb; /* Name of database iDb */
Table *pTab; /* Table being renamed */
char *zName = 0; /* NULL-terminated version of pName */
sqlite3 *db = pParse->db; /* Database connection */
Vdbe *v;
#ifndef SQLITE_OMIT_TRIGGER
char *zWhere = 0; /* Where clause to locate temp triggers */
#endif
if( sqlite3MallocFailed() ) goto exit_rename_table;
assert( pSrc->nSrc==1 );
pTab = sqlite3LocateTable(pParse, pSrc->a[0].zName, pSrc->a[0].zDatabase);
if( !pTab ) goto exit_rename_table;
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( IsVirtual(pTab) ){
sqlite3ErrorMsg(pParse, "virtual tables may not be altered");
goto exit_rename_table;
}
#endif
iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
zDb = db->aDb[iDb].zName;
/* Get a NULL terminated version of the new table name. */
zName = sqlite3NameFromToken(pName);
if( !zName ) goto exit_rename_table;
/* Check that a table or index named 'zName' does not already exist
** in database iDb. If so, this is an error.
*/
if( sqlite3FindTable(db, zName, zDb) || sqlite3FindIndex(db, zName, zDb) ){
sqlite3ErrorMsg(pParse,
"there is already another table or index with this name: %s", zName);
goto exit_rename_table;
}
/* Make sure it is not a system table being altered, or a reserved name
** that the table is being renamed to.
*/
if( strlen(pTab->zName)>6 && 0==sqlite3StrNICmp(pTab->zName, "sqlite_", 7) ){
sqlite3ErrorMsg(pParse, "table %s may not be altered", pTab->zName);
goto exit_rename_table;
}
if( SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
goto exit_rename_table;
}
#ifndef SQLITE_OMIT_AUTHORIZATION
/* Invoke the authorization callback. */
if( sqlite3AuthCheck(pParse, SQLITE_ALTER_TABLE, zDb, pTab->zName, 0) ){
goto exit_rename_table;
}
#endif
/* Begin a transaction and code the VerifyCookie for database iDb.
** Then modify the schema cookie (since the ALTER TABLE modifies the
** schema).
*/
v = sqlite3GetVdbe(pParse);
if( v==0 ){
goto exit_rename_table;
}
sqlite3BeginWriteOperation(pParse, 0, iDb);
sqlite3ChangeCookie(db, v, iDb);
/* Modify the sqlite_master table to use the new table name. */
sqlite3NestedParse(pParse,
"UPDATE %Q.%s SET "
#ifdef SQLITE_OMIT_TRIGGER
"sql = sqlite_rename_table(sql, %Q), "
#else
"sql = CASE "
"WHEN type = 'trigger' THEN sqlite_rename_trigger(sql, %Q)"
"ELSE sqlite_rename_table(sql, %Q) END, "
#endif
"tbl_name = %Q, "
"name = CASE "
"WHEN type='table' THEN %Q "
"WHEN name LIKE 'sqlite_autoindex%%' AND type='index' THEN "
"'sqlite_autoindex_' || %Q || substr(name, %d+18,10) "
"ELSE name END "
"WHERE tbl_name=%Q AND "
"(type='table' OR type='index' OR type='trigger');",
zDb, SCHEMA_TABLE(iDb), zName, zName, zName,
#ifndef SQLITE_OMIT_TRIGGER
zName,
#endif
zName, strlen(pTab->zName), pTab->zName
);
#ifndef SQLITE_OMIT_AUTOINCREMENT
/* If the sqlite_sequence table exists in this database, then update
** it with the new table name.
*/
if( sqlite3FindTable(db, "sqlite_sequence", zDb) ){
sqlite3NestedParse(pParse,
"UPDATE %Q.sqlite_sequence set name = %Q WHERE name = %Q",
zDb, zName, pTab->zName);
}
#endif
#ifndef SQLITE_OMIT_TRIGGER
/* If there are TEMP triggers on this table, modify the sqlite_temp_master
** table. Don't do this if the table being ALTERed is itself located in
** the temp database.
*/
if( (zWhere=whereTempTriggers(pParse, pTab))!=0 ){
sqlite3NestedParse(pParse,
"UPDATE sqlite_temp_master SET "
"sql = sqlite_rename_trigger(sql, %Q), "
"tbl_name = %Q "
"WHERE %s;", zName, zName, zWhere);
sqliteFree(zWhere);
}
#endif
/* Drop and reload the internal table schema. */
reloadTableSchema(pParse, pTab, zName);
exit_rename_table:
sqlite3SrcListDelete(pSrc);
sqliteFree(zName);
}
/*
** Generate code for a DELETE FROM statement.
**
** DELETE FROM table_wxyz WHERE a<5 AND b NOT NULL;
** \________/ \________________/
** pTabList pWhere
*/
void sqlite3DeleteFrom(
Parse *pParse, /* The parser context */
SrcList *pTabList, /* The table from which we should delete things */
Expr *pWhere /* The WHERE clause. May be null */
){
Vdbe *v; /* The virtual database engine */
Table *pTab; /* The table from which records will be deleted */
const char *zDb; /* Name of database holding pTab */
int end, addr = 0; /* A couple addresses of generated code */
int i; /* Loop counter */
WhereInfo *pWInfo; /* Information about the WHERE clause */
Index *pIdx; /* For looping over indices of the table */
int iCur; /* VDBE Cursor number for pTab */
sqlite3 *db; /* Main database structure */
AuthContext sContext; /* Authorization context */
NameContext sNC; /* Name context to resolve expressions in */
int iDb; /* Database number */
int memCnt = -1; /* Memory cell used for change counting */
int rcauth; /* Value returned by authorization callback */
#ifndef SQLITE_OMIT_TRIGGER
int isView; /* True if attempting to delete from a view */
Trigger *pTrigger; /* List of table triggers, if required */
#endif
memset(&sContext, 0, sizeof(sContext));
db = pParse->db;
if( pParse->nErr || db->mallocFailed ){
goto delete_from_cleanup;
}
assert( pTabList->nSrc==1 );
/* Locate the table which we want to delete. This table has to be
** put in an SrcList structure because some of the subroutines we
** will be calling are designed to work with multiple tables and expect
** an SrcList* parameter instead of just a Table* parameter.
*/
pTab = sqlite3SrcListLookup(pParse, pTabList);
if( pTab==0 ) goto delete_from_cleanup;
/* Figure out if we have any triggers and if the table being
** deleted from is a view
*/
#ifndef SQLITE_OMIT_TRIGGER
pTrigger = sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0, 0);
isView = pTab->pSelect!=0;
#else
# define pTrigger 0
# define isView 0
#endif
#ifdef SQLITE_OMIT_VIEW
# undef isView
# define isView 0
#endif
/* If pTab is really a view, make sure it has been initialized.
*/
if( sqlite3ViewGetColumnNames(pParse, pTab) ){
goto delete_from_cleanup;
}
if( sqlite3IsReadOnly(pParse, pTab, (pTrigger?1:0)) ){
goto delete_from_cleanup;
}
iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
assert( iDb<db->nDb );
zDb = db->aDb[iDb].zName;
rcauth = sqlite3AuthCheck(pParse, SQLITE_DELETE, pTab->zName, 0, zDb);
assert( rcauth==SQLITE_OK || rcauth==SQLITE_DENY || rcauth==SQLITE_IGNORE );
if( rcauth==SQLITE_DENY ){
goto delete_from_cleanup;
}
assert(!isView || pTrigger);
/* Assign cursor number to the table and all its indices.
*/
assert( pTabList->nSrc==1 );
iCur = pTabList->a[0].iCursor = pParse->nTab++;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
pParse->nTab++;
}
/* Start the view context
*/
if( isView ){
sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
}
/* Begin generating code.
*/
v = sqlite3GetVdbe(pParse);
if( v==0 ){
goto delete_from_cleanup;
}
if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
sqlite3BeginWriteOperation(pParse, 1, iDb);
/* If we are trying to delete from a view, realize that view into
** a ephemeral table.
*/
#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
if( isView ){
sqlite3MaterializeView(pParse, pTab, pWhere, iCur);
}
#endif
/* Resolve the column names in the WHERE clause.
*/
memset(&sNC, 0, sizeof(sNC));
sNC.pParse = pParse;
sNC.pSrcList = pTabList;
if( sqlite3ResolveExprNames(&sNC, pWhere) ){
goto delete_from_cleanup;
}
/* Initialize the counter of the number of rows deleted, if
** we are counting rows.
*/
if( db->flags & SQLITE_CountRows ){
memCnt = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Integer, 0, memCnt);
}
#ifndef SQLITE_OMIT_TRUNCATE_OPTIMIZATION
/* Special case: A DELETE without a WHERE clause deletes everything.
** It is easier just to erase the whole table. Prior to version 3.6.5,
** this optimization caused the row change count (the value returned by
** API function sqlite3_count_changes) to be set incorrectly. */
if( rcauth==SQLITE_OK && pWhere==0 && !pTrigger && !IsVirtual(pTab)
&& 0==sqlite3FkRequired(pParse, pTab, 0, 0)
){
assert( !isView );
sqlite3VdbeAddOp4(v, OP_Clear, pTab->tnum, iDb, memCnt,
pTab->zName, P4_STATIC);
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
assert( pIdx->pSchema==pTab->pSchema );
sqlite3VdbeAddOp2(v, OP_Clear, pIdx->tnum, iDb);
}
}else
#endif /* SQLITE_OMIT_TRUNCATE_OPTIMIZATION */
/* The usual case: There is a WHERE clause so we have to scan through
** the table and pick which records to delete.
*/
{
int iRowSet = ++pParse->nMem; /* Register for rowset of rows to delete */
int iRowid = ++pParse->nMem; /* Used for storing rowid values. */
int regRowid; /* Actual register containing rowids */
/* Collect rowids of every row to be deleted.
*/
sqlite3VdbeAddOp2(v, OP_Null, 0, iRowSet);
pWInfo = sqlite3WhereBegin(
pParse, pTabList, pWhere, 0, 0, WHERE_DUPLICATES_OK
);
if( pWInfo==0 ) goto delete_from_cleanup;
regRowid = sqlite3ExprCodeGetColumn(pParse, pTab, -1, iCur, iRowid, 0);
sqlite3VdbeAddOp2(v, OP_RowSetAdd, iRowSet, regRowid);
if( db->flags & SQLITE_CountRows ){
sqlite3VdbeAddOp2(v, OP_AddImm, memCnt, 1);
}
sqlite3WhereEnd(pWInfo);
/* Delete every item whose key was written to the list during the
** database scan. We have to delete items after the scan is complete
** because deleting an item can change the scan order. */
end = sqlite3VdbeMakeLabel(v);
/* Unless this is a view, open cursors for the table we are
** deleting from and all its indices. If this is a view, then the
** only effect this statement has is to fire the INSTEAD OF
** triggers. */
if( !isView ){
sqlite3OpenTableAndIndices(pParse, pTab, iCur, OP_OpenWrite);
}
addr = sqlite3VdbeAddOp3(v, OP_RowSetRead, iRowSet, end, iRowid);
/* Delete the row */
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( IsVirtual(pTab) ){
const char *pVTab = (const char *)sqlite3GetVTable(db, pTab);
sqlite3VtabMakeWritable(pParse, pTab);
sqlite3VdbeAddOp4(v, OP_VUpdate, 0, 1, iRowid, pVTab, P4_VTAB);
sqlite3VdbeChangeP5(v, OE_Abort);
sqlite3MayAbort(pParse);
}else
#endif
{
int count = (pParse->nested==0); /* True to count changes */
sqlite3GenerateRowDelete(pParse, pTab, iCur, iRowid, count, pTrigger, OE_Default);
}
/* End of the delete loop */
sqlite3VdbeAddOp2(v, OP_Goto, 0, addr);
sqlite3VdbeResolveLabel(v, end);
/* Close the cursors open on the table and its indexes. */
if( !isView && !IsVirtual(pTab) ){
for(i=1, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
sqlite3VdbeAddOp2(v, OP_Close, iCur + i, pIdx->tnum);
}
sqlite3VdbeAddOp1(v, OP_Close, iCur);
}
}
/* Update the sqlite_sequence table by storing the content of the
** maximum rowid counter values recorded while inserting into
** autoincrement tables.
*/
if( pParse->nested==0 && pParse->pTriggerTab==0 ){
sqlite3AutoincrementEnd(pParse);
}
/* Return the number of rows that were deleted. If this routine is
** generating code because of a call to sqlite3NestedParse(), do not
** invoke the callback function.
*/
if( (db->flags&SQLITE_CountRows) && !pParse->nested && !pParse->pTriggerTab ){
sqlite3VdbeAddOp2(v, OP_ResultRow, memCnt, 1);
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows deleted", SQLITE_STATIC);
}
delete_from_cleanup:
sqlite3AuthContextPop(&sContext);
sqlite3SrcListDelete(db, pTabList);
sqlite3ExprDelete(db, pWhere);
return;
}
