/*
** The non-standard VACUUM command is used to clean up the database,
** collapse free space, etc. It is modelled after the VACUUM command
** in PostgreSQL.
**
** In version 1.0.x of SQLite, the VACUUM command would call
** gdbm_reorganize() on all the database tables. But beginning
** with 2.0.0, SQLite no longer uses GDBM so this command has
** become a no-op.
*/
void sqlite3Vacuum(Parse *pParse) {
Vdbe *v = sqlite3GetVdbe(pParse);
if( v ) {
sqlite3VdbeAddOp2(v, OP_Vacuum, 0, 0);
}
return;
}
/*
** The non-standard VACUUM command is used to clean up the database,
** collapse free space, etc. It is modelled after the VACUUM command
** in PostgreSQL.
**
** In version 1.0.x of SQLite, the VACUUM command would call
** gdbm_reorganize() on all the database tables. But beginning
** with 2.0.0, SQLite no longer uses GDBM so this command has
** become a no-op.
*/
void sqlite3Vacuum(Parse *pParse, Token *pTableName){
Vdbe *v = sqlite3GetVdbe(pParse);
if( v ){
sqlite3VdbeAddOp(v, OP_Vacuum, 0, 0);
}
return;
}
/*
** Generate code for the trigger program associated with trigger p on
** table pTab. The reg, orconf and ignoreJump parameters passed to this
** function are the same as those described in the header function for
** sqlite3CodeRowTrigger()
*/
void sqlite3CodeRowTriggerDirect(
Parse *pParse, /* Parse context */
Trigger *p, /* Trigger to code */
Table *pTab, /* The table to code triggers from */
int reg, /* Reg array containing OLD.* and NEW.* values */
int orconf, /* ON CONFLICT policy */
int ignoreJump /* Instruction to jump to for RAISE(IGNORE) */
){
Vdbe *v = sqlite3GetVdbe(pParse); /* Main VM */
TriggerPrg *pPrg;
pPrg = getRowTrigger(pParse, p, pTab, orconf);
assert( pPrg || pParse->nErr || pParse->db->mallocFailed );
/* Code the OP_Program opcode in the parent VDBE. P4 of the OP_Program
** is a pointer to the sub-vdbe containing the trigger program. */
if( pPrg ){
int bRecursive = (p->zName && 0==(pParse->db->flags&SQLITE_RecTriggers));
sqlite3VdbeAddOp3(v, OP_Program, reg, ignoreJump, ++pParse->nMem);
sqlite3VdbeChangeP4(v, -1, (const char *)pPrg->pProgram, P4_SUBPROGRAM);
VdbeComment(
(v, "Call: %s.%s", (p->zName?p->zName:"fkey"), onErrorText(orconf)));
/* Set the P5 operand of the OP_Program instruction to non-zero if
** recursive invocation of this trigger program is disallowed. Recursive
** invocation is disallowed if (a) the sub-program is really a trigger,
** not a foreign key action, and (b) the flag to enable recursive triggers
** is clear. */
sqlite3VdbeChangeP5(v, (u8)bRecursive);
}
}
/* Generate code to return a string value */
static void codec_vdbe_return_static_string(Parse *pParse, const char *zLabel, const char *value){
Vdbe *v = sqlite3GetVdbe(pParse);
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, zLabel, SQLITE_STATIC);
sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, value, 0);
sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
}
/*
** The VACUUM command is used to clean up the database,
** collapse free space, etc. It is modelled after the VACUUM command
** in PostgreSQL. The VACUUM command works as follows:
**
** (1) Create a new transient database file
** (2) Copy all content from the database being vacuumed into
** the new transient database file
** (3) Copy content from the transient database back into the
** original database.
**
** The transient database requires temporary disk space approximately
** equal to the size of the original database. The copy operation of
** step (3) requires additional temporary disk space approximately equal
** to the size of the original database for the rollback journal.
** Hence, temporary disk space that is approximately 2x the size of the
** original database is required. Every page of the database is written
** approximately 3 times: Once for step (2) and twice for step (3).
** Two writes per page are required in step (3) because the original
** database content must be written into the rollback journal prior to
** overwriting the database with the vacuumed content.
**
** Only 1x temporary space and only 1x writes would be required if
** the copy of step (3) were replaced by deleting the original database
** and renaming the transient database as the original. But that will
** not work if other processes are attached to the original database.
** And a power loss in between deleting the original and renaming the
** transient would cause the database file to appear to be deleted
** following reboot.
*/
void sqlite3Vacuum(Parse *pParse, Token *pNm, Expr *pInto){
Vdbe *v = sqlite3GetVdbe(pParse);
int iDb = 0;
if( v==0 ) goto build_vacuum_end;
if( pNm ){
#ifndef SQLITE_BUG_COMPATIBLE_20160819
/* Default behavior: Report an error if the argument to VACUUM is
** not recognized */
iDb = sqlite3TwoPartName(pParse, pNm, pNm, &pNm);
if( iDb<0 ) goto build_vacuum_end;
#else
/* When SQLITE_BUG_COMPATIBLE_20160819 is defined, unrecognized arguments
** to VACUUM are silently ignored. This is a back-out of a bug fix that
** occurred on 2016-08-19 (https://www.sqlite.org/src/info/083f9e6270).
** The buggy behavior is required for binary compatibility with some
** legacy applications. */
iDb = sqlite3FindDb(pParse->db, pNm);
if( iDb<0 ) iDb = 0;
#endif
}
if( iDb!=1 ){
int iIntoReg = 0;
if( pInto && sqlite3ResolveSelfReference(pParse,0,0,pInto,0)==0 ){
iIntoReg = ++pParse->nMem;
sqlite3ExprCode(pParse, pInto, iIntoReg);
}
sqlite3VdbeAddOp2(v, OP_Vacuum, iDb, iIntoReg);
sqlite3VdbeUsesBtree(v, iDb);
}
build_vacuum_end:
sqlite3ExprDelete(pParse->db, pInto);
return;
}
/*
** Check to see if zRight and zLeft refer to a pragma that queries
** or changes one of the flags in db->flags. Return 1 if so and 0 if not.
** Also, implement the pragma.
*/
static int flagPragma(Parse *pParse, const char *zLeft, const char *zRight){
static const struct sPragmaType {
const char *zName; /* Name of the pragma */
int mask; /* Mask for the db->flags value */
} aPragma[] = {
{ "full_column_names", SQLITE_FullColNames },
{ "short_column_names", SQLITE_ShortColNames },
{ "count_changes", SQLITE_CountRows },
{ "empty_result_callbacks", SQLITE_NullCallback },
{ "legacy_file_format", SQLITE_LegacyFileFmt },
{ "fullfsync", SQLITE_FullFSync },
#ifdef SQLITE_DEBUG
{ "sql_trace", SQLITE_SqlTrace },
{ "vdbe_listing", SQLITE_VdbeListing },
{ "vdbe_trace", SQLITE_VdbeTrace },
#endif
#ifndef SQLITE_OMIT_CHECK
{ "ignore_check_constraints", SQLITE_IgnoreChecks },
#endif
/* The following is VERY experimental */
{ "writable_schema", SQLITE_WriteSchema|SQLITE_RecoveryMode },
{ "omit_readlock", SQLITE_NoReadlock },
/* TODO: Maybe it shouldn't be possible to change the ReadUncommitted
** flag if there are any active statements. */
{ "read_uncommitted", SQLITE_ReadUncommitted },
};
int i;
const struct sPragmaType *p;
for(i=0, p=aPragma; i<sizeof(aPragma)/sizeof(aPragma[0]); i++, p++){
if( sqlite3StrICmp(zLeft, p->zName)==0 ){
sqlite3 *db = pParse->db;
Vdbe *v;
v = sqlite3GetVdbe(pParse);
if( v ){
if( zRight==0 ){
returnSingleInt(pParse, p->zName, (db->flags & p->mask)!=0 );
}else{
if( getBoolean(zRight) ){
db->flags |= p->mask;
}else{
db->flags &= ~p->mask;
}
/* Many of the flag-pragmas modify the code generated by the SQL
** compiler (eg. count_changes). So add an opcode to expire all
** compiled SQL statements after modifying a pragma value.
*/
sqlite3VdbeAddOp2(v, OP_Expire, 0, 0);
}
}
return 1;
}
}
return 0;
}
/*
** Generate code to return a single integer value.
*/
static void returnSingleInt(Parse *pParse, const char *zLabel, int value){
Vdbe *v = sqlite3GetVdbe(pParse);
sqlite3VdbeAddOp(v, OP_Integer, value, 0);
if( pParse->explain==0 ){
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, zLabel, P3_STATIC);
}
sqlite3VdbeAddOp(v, OP_Callback, 1, 0);
}
/*
** Generate code to return a single integer value.
*/
static void returnSingleInt(Parse *pParse, const char *zLabel, int value){
Vdbe *v = sqlite3GetVdbe(pParse);
int mem = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Integer, value, mem);
if( pParse->explain==0 ){
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, zLabel, P4_STATIC);
}
sqlite3VdbeAddOp2(v, OP_ResultRow, mem, 1);
}
/*
** Drop a trigger given a pointer to that trigger.
*/
void sqlite3DropTriggerPtr(Parse *pParse, Trigger *pTrigger){
Table *pTable;
Vdbe *v;
sqlite3 *db = pParse->db;
int iDb;
iDb = sqlite3SchemaToIndex(pParse->db, pTrigger->pSchema);
assert( iDb>=0 && iDb<db->nDb );
pTable = tableOfTrigger(pTrigger);
assert( pTable );
assert( pTable->pSchema==pTrigger->pSchema || iDb==1 );
#ifndef SQLITE_OMIT_AUTHORIZATION
{
int code = SQLITE_DROP_TRIGGER;
const char *zDb = db->aDb[iDb].zName;
const char *zTab = SCHEMA_TABLE(iDb);
if( iDb==1 ) code = SQLITE_DROP_TEMP_TRIGGER;
if( sqlite3AuthCheck(pParse, code, pTrigger->zName, pTable->zName, zDb) ||
sqlite3AuthCheck(pParse, SQLITE_DELETE, zTab, 0, zDb) ){
return;
}
}
#endif
/* Generate code to destroy the database record of the trigger.
*/
assert( pTable!=0 );
if( (v = sqlite3GetVdbe(pParse))!=0 ){
int base;
static const int iLn = VDBE_OFFSET_LINENO(2);
static const VdbeOpList dropTrigger[] = {
{ OP_Rewind, 0, ADDR(9), 0},
{ OP_String8, 0, 1, 0}, /* 1 */
{ OP_Column, 0, 1, 2},
{ OP_Ne, 2, ADDR(8), 1},
{ OP_String8, 0, 1, 0}, /* 4: "trigger" */
{ OP_Column, 0, 0, 2},
{ OP_Ne, 2, ADDR(8), 1},
{ OP_Delete, 0, 0, 0},
{ OP_Next, 0, ADDR(1), 0}, /* 8 */
};
sqlite3BeginWriteOperation(pParse, 0, iDb);
sqlite3OpenMasterTable(pParse, iDb);
base = sqlite3VdbeAddOpList(v, ArraySize(dropTrigger), dropTrigger, iLn);
sqlite3VdbeChangeP4(v, base+1, pTrigger->zName, P4_TRANSIENT);
sqlite3VdbeChangeP4(v, base+4, "trigger", P4_STATIC);
sqlite3ChangeCookie(pParse, iDb);
sqlite3VdbeAddOp2(v, OP_Close, 0, 0);
sqlite3VdbeAddOp4(v, OP_DropTrigger, iDb, 0, 0, pTrigger->zName, 0);
if( pParse->nMem<3 ){
pParse->nMem = 3;
}
}
}
/*
** This routine generates code that opens the sqlite_stat1 table on cursor
** iStatCur.
**
** If the sqlite_stat1 tables does not previously exist, it is created.
** If it does previously exist, all entires associated with table zWhere
** are removed. If zWhere==0 then all entries are removed.
*/
static void openStatTable(
Parse *pParse, /* Parsing context */
int iDb, /* The database we are looking in */
int iStatCur, /* Open the sqlite_stat1 table on this cursor */
const char *zWhere /* Delete entries associated with this table */
){
sqlite3 *db = pParse->db;
Db *pDb;
int iRootPage;
Table *pStat;
Vdbe *v = sqlite3GetVdbe(pParse);
if( v==0 ) return;
assert( sqlite3BtreeHoldsAllMutexes(db) );
assert( sqlite3VdbeDb(v)==db );
pDb = &db->aDb[iDb];
if( (pStat = sqlite3FindTable(db, "sqlite_stat1", pDb->zName))==0 ){
/* The sqlite_stat1 tables does not exist. Create it.
** Note that a side-effect of the CREATE TABLE statement is to leave
** the rootpage of the new table on the top of the stack. This is
** important because the OpenWrite opcode below will be needing it. */
sqlite3NestedParse(pParse,
"CREATE TABLE %Q.sqlite_stat1(tbl,idx,stat)",
pDb->zName
);
iRootPage = 0; /* Cause rootpage to be taken from top of stack */
}else if( zWhere ){
/* The sqlite_stat1 table exists. Delete all entries associated with
** the table zWhere. */
sqlite3NestedParse(pParse,
"DELETE FROM %Q.sqlite_stat1 WHERE tbl=%Q",
pDb->zName, zWhere
);
iRootPage = pStat->tnum;
}else{
/* The sqlite_stat1 table already exists. Delete all rows. */
iRootPage = pStat->tnum;
sqlite3VdbeAddOp(v, OP_Clear, pStat->tnum, iDb);
}
/* Open the sqlite_stat1 table for writing. Unless it was created
** by this vdbe program, lock it for writing at the shared-cache level.
** If this vdbe did create the sqlite_stat1 table, then it must have
** already obtained a schema-lock, making the write-lock redundant.
*/
if( iRootPage>0 ){
sqlite3TableLock(pParse, iDb, iRootPage, 1, "sqlite_stat1");
}
sqlite3VdbeAddOp(v, OP_Integer, iDb, 0);
sqlite3VdbeAddOp(v, OP_OpenWrite, iStatCur, iRootPage);
sqlite3VdbeAddOp(v, OP_SetNumColumns, iStatCur, 3);
}
/*
** Drop a trigger given a pointer to that trigger. If nested is false,
** then also generate code to remove the trigger from the SQLITE_MASTER
** table.
*/
void sqlite3DropTriggerPtr(Parse *pParse, Trigger *pTrigger, int nested){
Table *pTable;
Vdbe *v;
sqlite3 *db = pParse->db;
int iDb;
iDb = pTrigger->iDb;
assert( iDb>=0 && iDb<db->nDb );
pTable = tableOfTrigger(db, pTrigger);
assert(pTable);
assert( pTable->iDb==iDb || iDb==1 );
#ifndef SQLITE_OMIT_AUTHORIZATION
{
int code = SQLITE_DROP_TRIGGER;
const char *zDb = db->aDb[iDb].zName;
const char *zTab = SCHEMA_TABLE(iDb);
if( iDb==1 ) code = SQLITE_DROP_TEMP_TRIGGER;
if( sqlite3AuthCheck(pParse, code, pTrigger->name, pTable->zName, zDb) ||
sqlite3AuthCheck(pParse, SQLITE_DELETE, zTab, 0, zDb) ){
return;
}
}
#endif
/* Generate code to destroy the database record of the trigger.
*/
if( pTable!=0 && (v = sqlite3GetVdbe(pParse))!=0 ){
int base;
static const VdbeOpList dropTrigger[] = {
{ OP_Rewind, 0, ADDR(9), 0},
{ OP_String8, 0, 0, 0}, /* 1 */
{ OP_Column, 0, 1, 0},
{ OP_Ne, 0, ADDR(8), 0},
{ OP_String8, 0, 0, "trigger"},
{ OP_Column, 0, 0, 0},
{ OP_Ne, 0, ADDR(8), 0},
{ OP_Delete, 0, 0, 0},
{ OP_Next, 0, ADDR(1), 0}, /* 8 */
};
sqlite3BeginWriteOperation(pParse, 0, iDb);
sqlite3OpenMasterTable(v, iDb);
base = sqlite3VdbeAddOpList(v, ArraySize(dropTrigger), dropTrigger);
sqlite3VdbeChangeP3(v, base+1, pTrigger->name, 0);
sqlite3ChangeCookie(db, v, iDb);
sqlite3VdbeAddOp(v, OP_Close, 0, 0);
sqlite3VdbeOp3(v, OP_DropTrigger, iDb, 0, pTrigger->name, 0);
}
}
/*
** Generate code that will open a table for reading.
*/
void sqlite3OpenTable(
Parse *p, /* Generate code into this VDBE */
int iCur, /* The cursor number of the table */
int iDb, /* The database index in sqlite3.aDb[] */
Table *pTab, /* The table to be opened */
int opcode /* OP_OpenRead or OP_OpenWrite */
){
Vdbe *v = sqlite3GetVdbe(p);
assert( opcode==OP_OpenWrite || opcode==OP_OpenRead );
sqlite3TableLock(p, iDb, pTab->tnum, (opcode==OP_OpenWrite), pTab->zName);
sqlite3VdbeAddOp(v, OP_Integer, iDb, 0);
VdbeComment((v, "# %s", pTab->zName));
sqlite3VdbeAddOp(v, opcode, iCur, pTab->tnum);
sqlite3VdbeAddOp(v, OP_SetNumColumns, iCur, pTab->nCol);
}
/*
** This routine generates code to finish the INSERT or UPDATE operation
** that was started by a prior call to sqlite3GenerateConstraintChecks.
** The stack must contain keys for all active indices followed by data
** and the rowid for the new entry. This routine creates the new
** entries in all indices and in the main table.
**
** The arguments to this routine should be the same as the first six
** arguments to sqlite3GenerateConstraintChecks.
*/
void sqlite3CompleteInsertion(
Parse *pParse, /* The parser context */
Table *pTab, /* the table into which we are inserting */
int base, /* Index of a read/write cursor pointing at pTab */
char *aIdxUsed, /* Which indices are used. NULL means all are used */
int rowidChng, /* True if the record number will change */
int isUpdate, /* True for UPDATE, False for INSERT */
int newIdx /* Index of NEW table for triggers. -1 if none */
){
int i;
Vdbe *v;
int nIdx;
Index *pIdx;
int pik_flags;
v = sqlite3GetVdbe(pParse);
assert( v!=0 );
assert( pTab->pSelect==0 ); /* This table is not a VIEW */
for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){}
for(i=nIdx-1; i>=0; i--){
if( aIdxUsed && aIdxUsed[i]==0 ) continue;
sqlite3VdbeAddOp(v, OP_IdxInsert, base+i+1, 0);
}
sqlite3VdbeAddOp(v, OP_MakeRecord, pTab->nCol, 0);
sqlite3TableAffinityStr(v, pTab);
#ifndef SQLITE_OMIT_TRIGGER
if( newIdx>=0 ){
sqlite3VdbeAddOp(v, OP_Dup, 1, 0);
sqlite3VdbeAddOp(v, OP_Dup, 1, 0);
sqlite3VdbeAddOp(v, OP_Insert, newIdx, 0);
}
#endif
if( pParse->nested ){
pik_flags = 0;
}else{
pik_flags = OPFLAG_NCHANGE;
pik_flags |= (isUpdate?OPFLAG_ISUPDATE:OPFLAG_LASTROWID);
}
sqlite3VdbeAddOp(v, OP_Insert, base, pik_flags);
if( !pParse->nested ){
sqlite3VdbeChangeP3(v, -1, pTab->zName, P3_STATIC);
}
if( isUpdate && rowidChng ){
sqlite3VdbeAddOp(v, OP_Pop, 1, 0);
}
}
/*
** Check to see if zRight and zLeft refer to a pragma that queries
** or changes one of the flags in db->flags. Return 1 if so and 0 if not.
** Also, implement the pragma.
*/
static int flagPragma(Parse *pParse, const char *zLeft, const char *zRight){
static const struct sPragmaType {
const char *zName; /* Name of the pragma */
int mask; /* Mask for the db->flags value */
} aPragma[] = {
{ "vdbe_trace", SQLITE_VdbeTrace },
{ "sql_trace", SQLITE_SqlTrace },
{ "vdbe_listing", SQLITE_VdbeListing },
{ "full_column_names", SQLITE_FullColNames },
{ "short_column_names", SQLITE_ShortColNames },
{ "count_changes", SQLITE_CountRows },
{ "empty_result_callbacks", SQLITE_NullCallback },
/* The following is VERY experimental */
{ "writable_schema", SQLITE_WriteSchema },
{ "omit_readlock", SQLITE_NoReadlock },
};
int i;
const struct sPragmaType *p;
for(i=0, p=aPragma; i<sizeof(aPragma)/sizeof(aPragma[0]); i++, p++){
if( sqlite3StrICmp(zLeft, p->zName)==0 ){
sqlite3 *db = pParse->db;
Vdbe *v;
v = sqlite3GetVdbe(pParse);
if( v ){
if( zRight==0 ){
returnSingleInt(pParse, p->zName, (db->flags & p->mask)!=0 );
}else{
if( getBoolean(zRight) ){
db->flags |= p->mask;
}else{
db->flags &= ~p->mask;
}
}
/* If one of these pragmas is executed, any prepared statements
** need to be recompiled.
*/
sqlite3VdbeAddOp(v, OP_Expire, 0, 0);
}
return 1;
}
}
return 0;
}
/*
** This routine generates code that opens the sqlite_stat1 table on cursor
** iStatCur.
**
** If the sqlite_stat1 tables does not previously exist, it is created.
** If it does previously exist, all entires associated with table zWhere
** are removed. If zWhere==0 then all entries are removed.
*/
static void openStatTable(
Parse *pParse, /* Parsing context */
int iDb, /* The database we are looking in */
int iStatCur, /* Open the sqlite_stat1 table on this cursor */
const char *zWhere /* Delete entries associated with this table */
){
sqlite3 *db = pParse->db;
Db *pDb;
int iRootPage;
Table *pStat;
Vdbe *v = sqlite3GetVdbe(pParse);
pDb = &db->aDb[iDb];
if( (pStat = sqlite3FindTable(db, "sqlite_stat1", pDb->zName))==0 ){
/* The sqlite_stat1 tables does not exist. Create it.
** Note that a side-effect of the CREATE TABLE statement is to leave
** the rootpage of the new table on the top of the stack. This is
** important because the OpenWrite opcode below will be needing it. */
sqlite3NestedParse(pParse,
"CREATE TABLE %Q.sqlite_stat1(tbl,idx,stat)",
pDb->zName
);
iRootPage = 0; /* Cause rootpage to be taken from top of stack */
}else if( zWhere ){
/* The sqlite_stat1 table exists. Delete all entries associated with
** the table zWhere. */
sqlite3NestedParse(pParse,
"DELETE FROM %Q.sqlite_stat1 WHERE tbl=%Q",
pDb->zName, zWhere
);
iRootPage = pStat->tnum;
}else{
/* The sqlite_stat1 table already exists. Delete all rows. */
iRootPage = pStat->tnum;
sqlite3VdbeAddOp(v, OP_Clear, pStat->tnum, iDb);
}
/* Open the sqlite_stat1 table for writing.
*/
sqlite3VdbeAddOp(v, OP_Integer, iDb, 0);
sqlite3VdbeAddOp(v, OP_OpenWrite, iStatCur, iRootPage);
sqlite3VdbeAddOp(v, OP_SetNumColumns, iStatCur, 3);
}
/*
** This routine is called by the parser to process a DETACH statement:
**
** DETACH DATABASE dbname
**
** The pDbname argument is the name of the database in the DETACH statement.
*/
void sqlite3Detach(Parse *pParse, Token *pDbname){
int i;
sqlite3 *db;
Vdbe *v;
Db *pDb = 0;
char *zName;
v = sqlite3GetVdbe(pParse);
if( !v ) return;
sqlite3VdbeAddOp(v, OP_Expire, 0, 0);
sqlite3VdbeAddOp(v, OP_Halt, 0, 0);
if( pParse->explain ) return;
db = pParse->db;
zName = sqlite3NameFromToken(pDbname);
if( zName==0 ) return;
for(i=0; i<db->nDb; i++){
pDb = &db->aDb[i];
if( pDb->pBt==0 ) continue;
if( sqlite3StrICmp(pDb->zName, zName)==0 ) break;
}
if( i>=db->nDb ){
sqlite3ErrorMsg(pParse, "no such database: %z", zName);
return;
}
if( i<2 ){
sqlite3ErrorMsg(pParse, "cannot detach database %z", zName);
return;
}
sqliteFree(zName);
if( !db->autoCommit ){
sqlite3ErrorMsg(pParse, "cannot DETACH database within transaction");
pParse->rc = SQLITE_ERROR;
return;
}
#ifndef SQLITE_OMIT_AUTHORIZATION
if( sqlite3AuthCheck(pParse,SQLITE_DETACH,db->aDb[i].zName,0,0)!=SQLITE_OK ){
return;
}
#endif /* SQLITE_OMIT_AUTHORIZATION */
sqlite3BtreeClose(pDb->pBt);
pDb->pBt = 0;
sqlite3ResetInternalSchema(db, 0);
}
/*
** Generate code to drop and reload the internal representation of table
** pTab from the database, including triggers and temporary triggers.
** Argument zName is the name of the table in the database schema at
** the time the generated code is executed. This can be different from
** pTab->zName if this function is being called to code part of an
** "ALTER TABLE RENAME TO" statement.
生成代码删除和重新加载从数据库表pTab的内部表达示,
包括触发器和临时触发器。
参数zName在数据库模式中的表的名称生成的代码执行。
这可以不同于pTab - > zName如果这个函数被调用的代码的一部分“ALTER TABLE RENAME TO”声明。
*/
static void reloadTableSchema(Parse *pParse, Table *pTab, const char *zName){
Vdbe *v;
char *zWhere;
int iDb; /* Index of database containing pTab 包含pTab数据库索引*/
#ifndef SQLITE_OMIT_TRIGGER
Trigger *pTrig;
#endif
v = sqlite3GetVdbe(pParse);
if( NEVER(v==0) ) return;
assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );
iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
assert( iDb>=0 );
#ifndef SQLITE_OMIT_TRIGGER
/* Drop any table triggers from the internal schema. 降低任何表触发器内部模式。*/
for(pTrig=sqlite3TriggerList(pParse, pTab); pTrig; pTrig=pTrig->pNext){
int iTrigDb = sqlite3SchemaToIndex(pParse->db, pTrig->pSchema);
assert( iTrigDb==iDb || iTrigDb==1 );
sqlite3VdbeAddOp4(v, OP_DropTrigger, iTrigDb, 0, 0, pTrig->zName, 0);
}
#endif
/* Drop the table and index from the internal schema. 从内部模式中降低表和索引*/
sqlite3VdbeAddOp4(v, OP_DropTable, iDb, 0, 0, pTab->zName, 0);
/* Reload the table, index and permanent trigger schemas. 重载表、索引和不变的触发器模式*/
zWhere = sqlite3MPrintf(pParse->db, "tbl_name=%Q", zName);
if( !zWhere ) return;
sqlite3VdbeAddParseSchemaOp(v, iDb, zWhere);
#ifndef SQLITE_OMIT_TRIGGER
/* Now, if the table is not stored in the temp database, reload any temp
** triggers. Don't use IN(...) in case SQLITE_OMIT_SUBQUERY is defined.
现在，如果表没有在临时数据库中存储，那么重载任何临时触发器。
不要用IN(...)在 SQLITE_OMIT_SUBQUERY被默认的情况下。
*/
if( (zWhere=whereTempTriggers(pParse, pTab))!=0 ){
sqlite3VdbeAddParseSchemaOp(v, 1, zWhere);
}
#endif
}
/*
** Generate code to make sure the file format number is at least minFormat.
** The generated code will increase the file format number if necessary.
*/
void sqlite3MinimumFileFormat(Parse *pParse, int iDb, int minFormat){
Vdbe *v;
v = sqlite3GetVdbe(pParse);
/* The VDBE should have been allocated before this routine is called.
** If that allocation failed, we would have quit before reaching this
** point */
if( ALWAYS(v) ){
int r1 = sqlite3GetTempReg(pParse);
int r2 = sqlite3GetTempReg(pParse);
int j1;
sqlite3VdbeAddOp3(v, OP_ReadCookie, iDb, r1, BTREE_FILE_FORMAT);
sqlite3VdbeUsesBtree(v, iDb);
sqlite3VdbeAddOp2(v, OP_Integer, minFormat, r2);
j1 = sqlite3VdbeAddOp3(v, OP_Ge, r2, 0, r1);
sqlite3VdbeAddOp3(v, OP_SetCookie, iDb, BTREE_FILE_FORMAT, r2);
sqlite3VdbeJumpHere(v, j1);
sqlite3ReleaseTempReg(pParse, r1);
sqlite3ReleaseTempReg(pParse, r2);
}
}
/*
** Generate code to drop and reload the internal representation of table
** pTab from the database, including triggers and temporary triggers.
** Argument zName is the name of the table in the database schema at
** the time the generated code is executed. This can be different from
** pTab->zName if this function is being called to code part of an
** "ALTER TABLE RENAME TO" statement.
*/
static void reloadTableSchema(Parse *pParse, Table *pTab, const char *zName){
Vdbe *v;
char *zWhere;
int iDb; /* Index of database containing pTab */
#ifndef SQLITE_OMIT_TRIGGER
Trigger *pTrig;
#endif
v = sqlite3GetVdbe(pParse);
if( !v ) return;
assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );
iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
assert( iDb>=0 );
#ifndef SQLITE_OMIT_TRIGGER
/* Drop any table triggers from the internal schema. */
for(pTrig=pTab->pTrigger; pTrig; pTrig=pTrig->pNext){
int iTrigDb = sqlite3SchemaToIndex(pParse->db, pTrig->pSchema);
assert( iTrigDb==iDb || iTrigDb==1 );
sqlite3VdbeAddOp4(v, OP_DropTrigger, iTrigDb, 0, 0, pTrig->name, 0);
}
#endif
/* Drop the table and index from the internal schema */
sqlite3VdbeAddOp4(v, OP_DropTable, iDb, 0, 0, pTab->zName, 0);
/* Reload the table, index and permanent trigger schemas. */
zWhere = sqlite3MPrintf(pParse->db, "tbl_name=%Q", zName);
if( !zWhere ) return;
sqlite3VdbeAddOp4(v, OP_ParseSchema, iDb, 0, 0, zWhere, P4_DYNAMIC);
#ifndef SQLITE_OMIT_TRIGGER
/* Now, if the table is not stored in the temp database, reload any temp
** triggers. Don't use IN(...) in case SQLITE_OMIT_SUBQUERY is defined.
*/
if( (zWhere=whereTempTriggers(pParse, pTab))!=0 ){
sqlite3VdbeAddOp4(v, OP_ParseSchema, 1, 0, 0, zWhere, P4_DYNAMIC);
}
#endif
}
/*
** This function is called to generate code that runs when table pTab is
** being dropped from the database. The SrcList passed as the second argument
** to this function contains a single entry guaranteed to resolve to
** table pTab.
**
** Normally, no code is required. However, if either
**
** (a) The table is the parent table of a FK constraint, or
** (b) The table is the child table of a deferred FK constraint and it is
** determined at runtime that there are outstanding deferred FK
** constraint violations in the database,
**
** then the equivalent of "DELETE FROM <tbl>" is executed before dropping
** the table from the database. Triggers are disabled while running this
** DELETE, but foreign key actions are not.
*/
void sqlite3FkDropTable(Parse *pParse, SrcList *pName, Table *pTab){
sqlite3 *db = pParse->db;
if( (db->flags&SQLITE_ForeignKeys) && !IsVirtual(pTab) && !pTab->pSelect ){
int iSkip = 0;
Vdbe *v = sqlite3GetVdbe(pParse);
assert( v ); /* VDBE has already been allocated */
if( sqlite3FkReferences(pTab)==0 ){
/* Search for a deferred foreign key constraint for which this table
** is the child table. If one cannot be found, return without
** generating any VDBE code. If one can be found, then jump over
** the entire DELETE if there are no outstanding deferred constraints
** when this statement is run. */
FKey *p;
for(p=pTab->pFKey; p; p=p->pNextFrom){
if( p->isDeferred ) break;
}
if( !p ) return;
iSkip = sqlite3VdbeMakeLabel(v);
sqlite3VdbeAddOp2(v, OP_FkIfZero, 1, iSkip);
}
pParse->disableTriggers = 1;
sqlite3DeleteFrom(pParse, sqlite3SrcListDup(db, pName, 0), 0);
pParse->disableTriggers = 0;
/* If the DELETE has generated immediate foreign key constraint
** violations, halt the VDBE and return an error at this point, before
** any modifications to the schema are made. This is because statement
** transactions are not able to rollback schema changes. */
sqlite3VdbeAddOp2(v, OP_FkIfZero, 0, sqlite3VdbeCurrentAddr(v)+2);
sqlite3HaltConstraint(
pParse, OE_Abort, "foreign key constraint failed", P4_STATIC
);
if( iSkip ){
sqlite3VdbeResolveLabel(v, iSkip);
}
}
}
/*
** Generate code that will open cursors for a table and for all
** indices of that table. The "base" parameter is the cursor number used
** for the table. Indices are opened on subsequent cursors.
*/
void sqlite3OpenTableAndIndices(
Parse *pParse, /* Parsing context */
Table *pTab, /* Table to be opened */
int base, /* Cursor number assigned to the table */
int op /* OP_OpenRead or OP_OpenWrite */
){
int i;
Index *pIdx;
Vdbe *v = sqlite3GetVdbe(pParse);
assert( v!=0 );
sqlite3VdbeAddOp(v, OP_Integer, pTab->iDb, 0);
sqlite3VdbeAddOp(v, op, base, pTab->tnum);
sqlite3VdbeAddOp(v, OP_SetNumColumns, base, pTab->nCol);
for(i=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
sqlite3VdbeAddOp(v, OP_Integer, pIdx->iDb, 0);
sqlite3VdbeOp3(v, op, i+base, pIdx->tnum,
(char*)&pIdx->keyInfo, P3_KEYINFO);
}
if( pParse->nTab<=base+i ){
pParse->nTab = base+i;
}
}
/*
** Generate code that will open cursors for a table and for all
** indices of that table. The "base" parameter is the cursor number used
** for the table. Indices are opened on subsequent cursors.
*/
void sqlite3OpenTableAndIndices(
Parse *pParse, /* Parsing context */
Table *pTab, /* Table to be opened */
int base, /* Cursor number assigned to the table */
int op /* OP_OpenRead or OP_OpenWrite */
){
int i;
int iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
Index *pIdx;
Vdbe *v = sqlite3GetVdbe(pParse);
assert( v!=0 );
sqlite3OpenTable(pParse, base, iDb, pTab, op);
for(i=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);
assert( pIdx->pSchema==pTab->pSchema );
sqlite3VdbeAddOp(v, OP_Integer, iDb, 0);
VdbeComment((v, "# %s", pIdx->zName));
sqlite3VdbeOp3(v, op, i+base, pIdx->tnum, (char*)pKey, P3_KEYINFO_HANDOFF);
}
if( pParse->nTab<=base+i ){
pParse->nTab = base+i;
}
}
/*
** This routine generates code to finish the INSERT or UPDATE operation
** that was started by a prior call to sqlite3GenerateConstraintChecks.
** The stack must contain keys for all active indices followed by data
** and the recno for the new entry. This routine creates the new
** entries in all indices and in the main table.
**
** The arguments to this routine should be the same as the first six
** arguments to sqlite3GenerateConstraintChecks.
*/
void sqlite3CompleteInsertion(
Parse *pParse, /* The parser context */
Table *pTab, /* the table into which we are inserting */
int base, /* Index of a read/write cursor pointing at pTab */
char *aIdxUsed, /* Which indices are used. NULL means all are used */
int recnoChng, /* True if the record number will change */
int isUpdate, /* True for UPDATE, False for INSERT */
int newIdx /* Index of NEW table for triggers. -1 if none */
){
int i;
Vdbe *v;
int nIdx;
Index *pIdx;
int pik_flags;
v = sqlite3GetVdbe(pParse);
assert( v!=0 );
assert( pTab->pSelect==0 ); /* This table is not a VIEW */
for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){}
for(i=nIdx-1; i>=0; i--){
if( aIdxUsed && aIdxUsed[i]==0 ) continue;
sqlite3VdbeAddOp(v, OP_IdxPut, base+i+1, 0);
}
sqlite3VdbeAddOp(v, OP_MakeRecord, pTab->nCol, 0);
sqlite3TableAffinityStr(v, pTab);
if( newIdx>=0 ){
sqlite3VdbeAddOp(v, OP_Dup, 1, 0);
sqlite3VdbeAddOp(v, OP_Dup, 1, 0);
sqlite3VdbeAddOp(v, OP_PutIntKey, newIdx, 0);
}
pik_flags = (OPFLAG_NCHANGE|(isUpdate?0:OPFLAG_LASTROWID));
sqlite3VdbeAddOp(v, OP_PutIntKey, base, pik_flags);
if( isUpdate && recnoChng ){
sqlite3VdbeAddOp(v, OP_Pop, 1, 0);
}
}
/*
** Generate code to drop and reload the internal representation of table
** pTab from the database, including triggers and temporary triggers.
** Argument zName is the name of the table in the database schema at
** the time the generated code is executed. This can be different from
** pTab->zName if this function is being called to code part of an
** "ALTER TABLE RENAME TO" statement.
*/
static void reloadTableSchema(Parse *pParse, Table *pTab, const char *zName){
Vdbe *v;
char *zWhere;
int iDb;
#ifndef SQLITE_OMIT_TRIGGER
Trigger *pTrig;
#endif
v = sqlite3GetVdbe(pParse);
if( !v ) return;
iDb = pTab->iDb;
#ifndef SQLITE_OMIT_TRIGGER
/* Drop any table triggers from the internal schema. */
for(pTrig=pTab->pTrigger; pTrig; pTrig=pTrig->pNext){
assert( pTrig->iDb==iDb || pTrig->iDb==1 );
sqlite3VdbeOp3(v, OP_DropTrigger, pTrig->iDb, 0, pTrig->name, 0);
}
#endif
/* Drop the table and index from the internal schema */
sqlite3VdbeOp3(v, OP_DropTable, iDb, 0, pTab->zName, 0);
/* Reload the table, index and permanent trigger schemas. */
zWhere = sqlite3MPrintf("tbl_name=%Q", zName);
if( !zWhere ) return;
sqlite3VdbeOp3(v, OP_ParseSchema, iDb, 0, zWhere, P3_DYNAMIC);
#ifndef SQLITE_OMIT_TRIGGER
/* Now, if the table is not stored in the temp database, reload any temp
** triggers. Don't use IN(...) in case SQLITE_OMIT_SUBQUERY is defined.
*/
if( (zWhere=whereTempTriggers(pParse, pTab)) ){
sqlite3VdbeOp3(v, OP_ParseSchema, 1, 0, zWhere, P3_DYNAMIC);
}
#endif
}
/*
** Check to see if zRight and zLeft refer to a pragma that queries
** or changes one of the flags in db->flags. Return 1 if so and 0 if not.
** Also, implement the pragma.
*/
static int flagPragma(Parse *pParse, const char *zLeft, const char *zRight){
static const struct {
const char *zName; /* Name of the pragma */
int mask; /* Mask for the db->flags value */
} aPragma[] = {
{ "vdbe_trace", SQLITE_VdbeTrace },
{ "sql_trace", SQLITE_SqlTrace },
{ "vdbe_listing", SQLITE_VdbeListing },
#if 1 /* FIX ME: Remove the following pragmas */
{ "full_column_names", SQLITE_FullColNames },
{ "short_column_names", SQLITE_ShortColNames },
{ "count_changes", SQLITE_CountRows },
{ "empty_result_callbacks", SQLITE_NullCallback },
#endif
};
int i;
for(i=0; i<sizeof(aPragma)/sizeof(aPragma[0]); i++){
if( sqlite3StrICmp(zLeft, aPragma[i].zName)==0 ){
sqlite3 *db = pParse->db;
Vdbe *v;
if( zRight==0 ){
v = sqlite3GetVdbe(pParse);
if( v ){
returnSingleInt(pParse,
aPragma[i].zName, (db->flags&aPragma[i].mask)!=0);
}
}else if( getBoolean(zRight) ){
db->flags |= aPragma[i].mask;
}else{
db->flags &= ~aPragma[i].mask;
}
return 1;
}
}
return 0;
}
/*
** Drop a trigger given a pointer to that trigger.
*/
void sqlite3DropTriggerPtr(Parse *pParse, Trigger *pTrigger){
Table *pTable;
Vdbe *v;
sqlite3 *db = pParse->db;
int iDb;
iDb = sqlite3SchemaToIndex(pParse->db, pTrigger->pSchema);
assert( iDb>=0 && iDb<db->nDb );
pTable = tableOfTrigger(pTrigger);
assert( pTable );
assert( pTable->pSchema==pTrigger->pSchema || iDb==1 );
#ifndef SQLITE_OMIT_AUTHORIZATION
{
int code = SQLITE_DROP_TRIGGER;
const char *zDb = db->aDb[iDb].zDbSName;
const char *zTab = SCHEMA_TABLE(iDb);
if( iDb==1 ) code = SQLITE_DROP_TEMP_TRIGGER;
if( sqlite3AuthCheck(pParse, code, pTrigger->zName, pTable->zName, zDb) ||
sqlite3AuthCheck(pParse, SQLITE_DELETE, zTab, 0, zDb) ){
return;
}
}
#endif
/* Generate code to destroy the database record of the trigger.
*/
assert( pTable!=0 );
if( (v = sqlite3GetVdbe(pParse))!=0 ){
sqlite3NestedParse(pParse,
"DELETE FROM %Q.%s WHERE name=%Q AND type='trigger'",
db->aDb[iDb].zDbSName, MASTER_NAME, pTrigger->zName
);
sqlite3ChangeCookie(pParse, iDb);
sqlite3VdbeAddOp4(v, OP_DropTrigger, iDb, 0, 0, pTrigger->zName, 0);
}
}
/*
** 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 */
int i; /* Loop counter */
WhereInfo *pWInfo; /* Information about the WHERE clause */
Index *pIdx; /* For looping over indices of the table */
int iTabCur; /* Cursor number for the table */
int iDataCur = 0; /* VDBE cursor for the canonical data source */
int iIdxCur = 0; /* Cursor number of the first index */
int nIdx; /* Number of indices */
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 */
int eOnePass; /* ONEPASS_OFF or _SINGLE or _MULTI */
int aiCurOnePass[2]; /* The write cursors opened by WHERE_ONEPASS */
u8 *aToOpen = 0; /* Open cursor iTabCur+j if aToOpen[j] is true */
Index *pPk; /* The PRIMARY KEY index on the table */
int iPk = 0; /* First of nPk registers holding PRIMARY KEY value */
i16 nPk = 1; /* Number of columns in the PRIMARY KEY */
int iKey; /* Memory cell holding key of row to be deleted */
i16 nKey; /* Number of memory cells in the row key */
int iEphCur = 0; /* Ephemeral table holding all primary key values */
int iRowSet = 0; /* Register for rowset of rows to delete */
int addrBypass = 0; /* Address of jump over the delete logic */
int addrLoop = 0; /* Top of the delete loop */
int addrEphOpen = 0; /* Instruction to open the Ephemeral table */
int bComplex; /* True if there are triggers or FKs or
** subqueries in the WHERE clause */
#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;
bComplex = pTrigger || sqlite3FkRequired(pParse, pTab, 0, 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 );
rcauth = sqlite3AuthCheck(pParse, SQLITE_DELETE, pTab->zName, 0,
db->aDb[iDb].zDbSName);
assert( rcauth==SQLITE_OK || rcauth==SQLITE_DENY || rcauth==SQLITE_IGNORE );
if( rcauth==SQLITE_DENY ){
goto delete_from_cleanup;
}
assert(!isView || pTrigger);
/* Assign cursor numbers to the table and all its indices.
*/
assert( pTabList->nSrc==1 );
iTabCur = pTabList->a[0].iCursor = pParse->nTab++;
for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){
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
** an ephemeral table.
*/
#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
if( isView ){
sqlite3MaterializeView(pParse, pTab, pWhere, iTabCur);
iDataCur = iIdxCur = iTabCur;
}
#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
&& !bComplex
&& !IsVirtual(pTab)
#ifdef SQLITE_ENABLE_PREUPDATE_HOOK
&& db->xPreUpdateCallback==0
#endif
){
assert( !isView );
sqlite3TableLock(pParse, iDb, pTab->tnum, 1, pTab->zName);
if( HasRowid(pTab) ){
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 */
{
u16 wcf = WHERE_ONEPASS_DESIRED|WHERE_DUPLICATES_OK|WHERE_SEEK_TABLE;
if( sNC.ncFlags & NC_VarSelect ) bComplex = 1;
wcf |= (bComplex ? 0 : WHERE_ONEPASS_MULTIROW);
if( HasRowid(pTab) ){
/* For a rowid table, initialize the RowSet to an empty set */
pPk = 0;
nPk = 1;
iRowSet = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Null, 0, iRowSet);
}else{
/* For a WITHOUT ROWID table, create an ephemeral table used to
** hold all primary keys for rows to be deleted. */
pPk = sqlite3PrimaryKeyIndex(pTab);
assert( pPk!=0 );
nPk = pPk->nKeyCol;
iPk = pParse->nMem+1;
pParse->nMem += nPk;
iEphCur = pParse->nTab++;
addrEphOpen = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, iEphCur, nPk);
sqlite3VdbeSetP4KeyInfo(pParse, pPk);
}
/* Construct a query to find the rowid or primary key for every row
** to be deleted, based on the WHERE clause. Set variable eOnePass
** to indicate the strategy used to implement this delete:
**
** ONEPASS_OFF: Two-pass approach - use a FIFO for rowids/PK values.
** ONEPASS_SINGLE: One-pass approach - at most one row deleted.
** ONEPASS_MULTI: One-pass approach - any number of rows may be deleted.
*/
pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0, 0, wcf, iTabCur+1);
if( pWInfo==0 ) goto delete_from_cleanup;
eOnePass = sqlite3WhereOkOnePass(pWInfo, aiCurOnePass);
assert( IsVirtual(pTab)==0 || eOnePass!=ONEPASS_MULTI );
assert( IsVirtual(pTab) || bComplex || eOnePass!=ONEPASS_OFF );
/* Keep track of the number of rows to be deleted */
if( db->flags & SQLITE_CountRows ){
sqlite3VdbeAddOp2(v, OP_AddImm, memCnt, 1);
}
/* Extract the rowid or primary key for the current row */
if( pPk ){
for(i=0; i<nPk; i++){
assert( pPk->aiColumn[i]>=0 );
sqlite3ExprCodeGetColumnOfTable(v, pTab, iTabCur,
pPk->aiColumn[i], iPk+i);
}
iKey = iPk;
}else{
iKey = pParse->nMem + 1;
iKey = sqlite3ExprCodeGetColumn(pParse, pTab, -1, iTabCur, iKey, 0);
if( iKey>pParse->nMem ) pParse->nMem = iKey;
}
if( eOnePass!=ONEPASS_OFF ){
/* For ONEPASS, no need to store the rowid/primary-key. There is only
** one, so just keep it in its register(s) and fall through to the
** delete code. */
nKey = nPk; /* OP_Found will use an unpacked key */
aToOpen = sqlite3DbMallocRawNN(db, nIdx+2);
if( aToOpen==0 ){
sqlite3WhereEnd(pWInfo);
goto delete_from_cleanup;
}
memset(aToOpen, 1, nIdx+1);
aToOpen[nIdx+1] = 0;
if( aiCurOnePass[0]>=0 ) aToOpen[aiCurOnePass[0]-iTabCur] = 0;
if( aiCurOnePass[1]>=0 ) aToOpen[aiCurOnePass[1]-iTabCur] = 0;
if( addrEphOpen ) sqlite3VdbeChangeToNoop(v, addrEphOpen);
}else{
if( pPk ){
/* Add the PK key for this row to the temporary table */
iKey = ++pParse->nMem;
nKey = 0; /* Zero tells OP_Found to use a composite key */
sqlite3VdbeAddOp4(v, OP_MakeRecord, iPk, nPk, iKey,
sqlite3IndexAffinityStr(pParse->db, pPk), nPk);
sqlite3VdbeAddOp2(v, OP_IdxInsert, iEphCur, iKey);
}else{
/* Add the rowid of the row to be deleted to the RowSet */
nKey = 1; /* OP_Seek always uses a single rowid */
sqlite3VdbeAddOp2(v, OP_RowSetAdd, iRowSet, iKey);
}
}
/* If this DELETE cannot use the ONEPASS strategy, this is the
** end of the WHERE loop */
if( eOnePass!=ONEPASS_OFF ){
addrBypass = sqlite3VdbeMakeLabel(v);
}else{
sqlite3WhereEnd(pWInfo);
}
/* 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 ){
int iAddrOnce = 0;
if( eOnePass==ONEPASS_MULTI ){
iAddrOnce = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v);
}
testcase( IsVirtual(pTab) );
sqlite3OpenTableAndIndices(pParse, pTab, OP_OpenWrite, OPFLAG_FORDELETE,
iTabCur, aToOpen, &iDataCur, &iIdxCur);
assert( pPk || IsVirtual(pTab) || iDataCur==iTabCur );
assert( pPk || IsVirtual(pTab) || iIdxCur==iDataCur+1 );
if( eOnePass==ONEPASS_MULTI ) sqlite3VdbeJumpHere(v, iAddrOnce);
}
/* Set up a loop over the rowids/primary-keys that were found in the
** where-clause loop above.
*/
if( eOnePass!=ONEPASS_OFF ){
assert( nKey==nPk ); /* OP_Found will use an unpacked key */
if( !IsVirtual(pTab) && aToOpen[iDataCur-iTabCur] ){
assert( pPk!=0 || pTab->pSelect!=0 );
sqlite3VdbeAddOp4Int(v, OP_NotFound, iDataCur, addrBypass, iKey, nKey);
VdbeCoverage(v);
}
}else if( pPk ){
addrLoop = sqlite3VdbeAddOp1(v, OP_Rewind, iEphCur); VdbeCoverage(v);
sqlite3VdbeAddOp2(v, OP_RowKey, iEphCur, iKey);
assert( nKey==0 ); /* OP_Found will use a composite key */
}else{
addrLoop = sqlite3VdbeAddOp3(v, OP_RowSetRead, iRowSet, 0, iKey);
VdbeCoverage(v);
assert( nKey==1 );
}
/* 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, iKey, pVTab, P4_VTAB);
sqlite3VdbeChangeP5(v, OE_Abort);
assert( eOnePass==ONEPASS_OFF || eOnePass==ONEPASS_SINGLE );
sqlite3MayAbort(pParse);
if( eOnePass==ONEPASS_SINGLE && sqlite3IsToplevel(pParse) ){
pParse->isMultiWrite = 0;
}
}else
#endif
{
int count = (pParse->nested==0); /* True to count changes */
int iIdxNoSeek = -1;
if( bComplex==0 && aiCurOnePass[1]!=iDataCur ){
iIdxNoSeek = aiCurOnePass[1];
}
sqlite3GenerateRowDelete(pParse, pTab, pTrigger, iDataCur, iIdxCur,
iKey, nKey, count, OE_Default, eOnePass, iIdxNoSeek);
}
/* End of the loop over all rowids/primary-keys. */
if( eOnePass!=ONEPASS_OFF ){
sqlite3VdbeResolveLabel(v, addrBypass);
sqlite3WhereEnd(pWInfo);
}else if( pPk ){
sqlite3VdbeAddOp2(v, OP_Next, iEphCur, addrLoop+1); VdbeCoverage(v);
sqlite3VdbeJumpHere(v, addrLoop);
}else{
sqlite3VdbeGoto(v, addrLoop);
sqlite3VdbeJumpHere(v, addrLoop);
}
/* Close the cursors open on the table and its indexes. */
if( !isView && !IsVirtual(pTab) ){
if( !pPk ) sqlite3VdbeAddOp1(v, OP_Close, iDataCur);
for(i=0, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
sqlite3VdbeAddOp1(v, OP_Close, iIdxCur + i);
}
}
} /* End non-truncate path */
/* 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);
sqlite3DbFree(db, aToOpen);
return;
}
/*
** 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 *nt = 0; /* The trigger whose construction is finishing up */
sqlite *db = pParse->db; /* The database */
DbFixer sFix;
if( pParse->nErr || pParse->pNewTrigger==0 ) goto triggerfinish_cleanup;
nt = pParse->pNewTrigger;
pParse->pNewTrigger = 0;
nt->step_list = pStepList;
while( pStepList ){
pStepList->pTrig = nt;
pStepList = pStepList->pNext;
}
if( sqlite3FixInit(&sFix, pParse, nt->iDb, "trigger", &nt->nameToken)
&& sqlite3FixTriggerStep(&sFix, nt->step_list) ){
goto triggerfinish_cleanup;
}
/* if we are not initializing, and this trigger is not on a TEMP table,
** build the sqlite_master entry
*/
if( !db->init.busy ){
static VdbeOpList insertTrig[] = {
{ OP_NewRecno, 0, 0, 0 },
{ OP_String8, 0, 0, "trigger" },
{ OP_String8, 0, 0, 0 }, /* 2: trigger name */
{ OP_String8, 0, 0, 0 }, /* 3: table name */
{ OP_Integer, 0, 0, 0 },
{ OP_String8, 0, 0, "CREATE TRIGGER "},
{ OP_String8, 0, 0, 0 }, /* 6: SQL */
{ OP_Concat8, 2, 0, 0 },
{ OP_MakeRecord, 5, 0, "tttit" },
{ OP_PutIntKey, 0, 0, 0 },
};
int addr;
Vdbe *v;
/* Make an entry in the sqlite_master table */
v = sqlite3GetVdbe(pParse);
if( v==0 ) goto triggerfinish_cleanup;
sqlite3BeginWriteOperation(pParse, 0, nt->iDb);
sqlite3OpenMasterTable(v, nt->iDb);
addr = sqlite3VdbeAddOpList(v, ArraySize(insertTrig), insertTrig);
sqlite3VdbeChangeP3(v, addr+2, nt->name, 0);
sqlite3VdbeChangeP3(v, addr+3, nt->table, 0);
sqlite3VdbeChangeP3(v, addr+6, pAll->z, pAll->n);
if( nt->iDb!=0 ){
sqlite3ChangeCookie(db, v, nt->iDb);
}
sqlite3VdbeAddOp(v, OP_Close, 0, 0);
sqlite3EndWriteOperation(pParse);
}
if( !pParse->explain ){
Table *pTab;
sqlite3HashInsert(&db->aDb[nt->iDb].trigHash,
nt->name, strlen(nt->name)+1, nt);
pTab = sqlite3LocateTable(pParse, nt->table, db->aDb[nt->iTabDb].zName);
assert( pTab!=0 );
nt->pNext = pTab->pTrigger;
pTab->pTrigger = nt;
nt = 0;
}
triggerfinish_cleanup:
sqlite3DeleteTrigger(nt);
sqlite3DeleteTrigger(pParse->pNewTrigger);
pParse->pNewTrigger = 0;
sqlite3DeleteTriggerStep(pStepList);
}
/*
** Drop a trigger given a pointer to that trigger. If nested is false,
** then also generate code to remove the trigger from the SQLITE_MASTER
** table.
*/
void sqlite3DropTriggerPtr(Parse *pParse, Trigger *pTrigger, int nested){
Table *pTable;
Vdbe *v;
sqlite *db = pParse->db;
assert( pTrigger->iDb<db->nDb );
pTable = sqlite3FindTable(db,pTrigger->table,db->aDb[pTrigger->iTabDb].zName);
assert(pTable);
assert( pTable->iDb==pTrigger->iDb || pTrigger->iDb==1 );
#ifndef SQLITE_OMIT_AUTHORIZATION
{
int code = SQLITE_DROP_TRIGGER;
const char *zDb = db->aDb[pTrigger->iDb].zName;
const char *zTab = SCHEMA_TABLE(pTrigger->iDb);
if( pTrigger->iDb==1 ) code = SQLITE_DROP_TEMP_TRIGGER;
if( sqlite3AuthCheck(pParse, code, pTrigger->name, pTable->zName, zDb) ||
sqlite3AuthCheck(pParse, SQLITE_DELETE, zTab, 0, zDb) ){
return;
}
}
#endif
/* Generate code to destroy the database record of the trigger.
*/
if( pTable!=0 && (v = sqlite3GetVdbe(pParse))!=0 ){
int base;
static VdbeOpList dropTrigger[] = {
{ OP_Rewind, 0, ADDR(9), 0},
{ OP_String8, 0, 0, 0}, /* 1 */
{ OP_Column, 0, 1, 0},
{ OP_Ne, 0, ADDR(8), 0},
{ OP_String8, 0, 0, "trigger"},
{ OP_Column, 0, 0, 0},
{ OP_Ne, 0, ADDR(8), 0},
{ OP_Delete, 0, 0, 0},
{ OP_Next, 0, ADDR(1), 0}, /* 8 */
};
sqlite3BeginWriteOperation(pParse, 0, pTrigger->iDb);
sqlite3OpenMasterTable(v, pTrigger->iDb);
base = sqlite3VdbeAddOpList(v, ArraySize(dropTrigger), dropTrigger);
sqlite3VdbeChangeP3(v, base+1, pTrigger->name, 0);
sqlite3ChangeCookie(db, v, pTrigger->iDb);
sqlite3VdbeAddOp(v, OP_Close, 0, 0);
}
/*
** If this is not an "explain", then delete the trigger structure.
*/
if( !pParse->explain ){
const char *zName = pTrigger->name;
int nName = strlen(zName);
if( pTable->pTrigger == pTrigger ){
pTable->pTrigger = pTrigger->pNext;
}else{
Trigger *cc = pTable->pTrigger;
while( cc ){
if( cc->pNext == pTrigger ){
cc->pNext = cc->pNext->pNext;
break;
}
cc = cc->pNext;
}
assert(cc);
}
sqlite3HashInsert(&(db->aDb[pTrigger->iDb].trigHash), zName, nName+1, 0);
sqlite3DeleteTrigger(pTrigger);
}
}
/*
** 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;
int iReg;
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].zDbSName, MASTER_NAME,
pTab->zName,
pTab->zName,
zStmt,
pParse->regRowid
);
sqlite3DbFree(db, zStmt);
v = sqlite3GetVdbe(pParse);
sqlite3ChangeCookie(pParse, iDb);
sqlite3VdbeAddOp0(v, OP_Expire);
zWhere = sqlite3MPrintf(db, "name='%q' AND type='table'", pTab->zName);
sqlite3VdbeAddParseSchemaOp(v, iDb, zWhere);
iReg = ++pParse->nMem;
sqlite3VdbeLoadString(v, iReg, pTab->zName);
sqlite3VdbeAddOp2(v, OP_VCreate, iDb, iReg);
}
/* 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;
assert( sqlite3SchemaMutexHeld(db, 0, pSchema) );
pOld = sqlite3HashInsert(&pSchema->tblHash, zName, pTab);
if( pOld ){
sqlite3OomFault(db);
assert( pTab==pOld ); /* Malloc must have failed inside HashInsert() */
return;
}
pParse->pNewTable = 0;
}
}
