/*
** Make a copy of all components of the given trigger step. This has
** the effect of copying all Expr.token.z values into memory obtained
** from sqlite3_malloc(). As initially created, the Expr.token.z values
** all point to the input string that was fed to the parser. But that
** string is ephemeral - it will go away as soon as the sqlite3_exec()
** call that started the parser exits. This routine makes a persistent
** copy of all the Expr.token.z strings so that the TriggerStep structure
** will be valid even after the sqlite3_exec() call returns.
*/
static void sqlitePersistTriggerStep(sqlite3 *db, TriggerStep *p){
if( p->target.z ){
p->target.z = (u8*)sqlite3DbStrNDup(db, (char*)p->target.z, p->target.n);
p->target.dyn = 1;
}
if( p->pSelect ){
Select *pNew = sqlite3SelectDup(db, p->pSelect);
sqlite3SelectDelete(p->pSelect);
p->pSelect = pNew;
}
if( p->pWhere ){
Expr *pNew = sqlite3ExprDup(db, p->pWhere);
sqlite3ExprDelete(p->pWhere);
p->pWhere = pNew;
}
if( p->pExprList ){
ExprList *pNew = sqlite3ExprListDup(db, p->pExprList);
sqlite3ExprListDelete(p->pExprList);
p->pExprList = pNew;
}
if( p->pIdList ){
IdList *pNew = sqlite3IdListDup(db, p->pIdList);
sqlite3IdListDelete(p->pIdList);
p->pIdList = pNew;
}
}
/*
** Create a new sqlite3_value object, containing the value of pExpr.
**
** This only works for very simple expressions that consist of one constant
** token (i.e. "5", "5.1", "'a string'"). If the expression can
** be converted directly into a value, then the value is allocated and
** a pointer written to *ppVal. The caller is responsible for deallocating
** the value by passing it to sqlite3ValueFree() later on. If the expression
** cannot be converted to a value, then *ppVal is set to NULL.
*/
int sqlite3ValueFromExpr(
sqlite3 *db, /* The database connection */
Expr *pExpr, /* The expression to evaluate */
u8 enc, /* Encoding to use */
u8 affinity, /* Affinity to use */
sqlite3_value **ppVal /* Write the new value here */
){
int op;
char *zVal = 0;
sqlite3_value *pVal = 0;
if( !pExpr ){
*ppVal = 0;
return SQLITE_OK;
}
op = pExpr->op;
if( op==TK_STRING || op==TK_FLOAT || op==TK_INTEGER ){
zVal = sqlite3DbStrNDup(db, (char*)pExpr->token.z, pExpr->token.n);
pVal = sqlite3ValueNew(db);
if( !zVal || !pVal ) goto no_mem;
sqlite3Dequote(zVal);
sqlite3ValueSetStr(pVal, -1, zVal, SQLITE_UTF8, SQLITE_DYNAMIC);
if( (op==TK_INTEGER || op==TK_FLOAT ) && affinity==SQLITE_AFF_NONE ){
sqlite3ValueApplyAffinity(pVal, SQLITE_AFF_NUMERIC, enc);
}else{
sqlite3ValueApplyAffinity(pVal, affinity, enc);
}
}else if( op==TK_UMINUS ) {
if( SQLITE_OK==sqlite3ValueFromExpr(db,pExpr->pLeft,enc,affinity,&pVal) ){
pVal->u.i = -1 * pVal->u.i;
pVal->r = -1.0 * pVal->r;
}
}
#ifndef SQLITE_OMIT_BLOB_LITERAL
else if( op==TK_BLOB ){
int nVal;
assert( pExpr->token.n>=3 );
assert( pExpr->token.z[0]=='x' || pExpr->token.z[0]=='X' );
assert( pExpr->token.z[1]=='\'' );
assert( pExpr->token.z[pExpr->token.n-1]=='\'' );
pVal = sqlite3ValueNew(db);
if( !pVal ) goto no_mem;
nVal = pExpr->token.n - 3;
zVal = (char*)pExpr->token.z + 2;
sqlite3VdbeMemSetStr(pVal, sqlite3HexToBlob(db, zVal, nVal), nVal/2,
0, SQLITE_DYNAMIC);
}
#endif
*ppVal = pVal;
return SQLITE_OK;
no_mem:
db->mallocFailed = 1;
sqlite3DbFree(db, zVal);
sqlite3ValueFree(pVal);
*ppVal = 0;
return SQLITE_NOMEM;
}
/*
** The text between zStart and zEnd represents a phrase within a larger
** SQL statement. Make a copy of this phrase in space obtained form
** sqlite3DbMalloc(). Omit leading and trailing whitespace.
*/
char *sqlite3DbSpanDup(sqlite3 *db, const char *zStart, const char *zEnd){
int n;
while( sqlite3Isspace(zStart[0]) ) zStart++;
n = (int)(zEnd - zStart);
while( ALWAYS(n>0) && sqlite3Isspace(zStart[n-1]) ) n--;
return sqlite3DbStrNDup(db, zStart, n);
}
/*
** This routine takes the module argument that has been accumulating
** in pParse->zArg[] and appends it to the list of arguments on the
** virtual table currently under construction in pParse->pTable.
*/
static void addArgumentToVtab(Parse *pParse){
if( pParse->sArg.z && pParse->pNewTable ){
const char *z = (const char*)pParse->sArg.z;
int n = pParse->sArg.n;
sqlite3 *db = pParse->db;
addModuleArgument(db, pParse->pNewTable, sqlite3DbStrNDup(db, z, n));
}
}
static void renameParentFunc(
sqlite3_context *context,
int NotUsed,
sqlite3_value **argv
){
sqlite3 *db = sqlite3_context_db_handle(context);
char *zOutput = 0;
char *zResult;
unsigned char const *zInput = sqlite3_value_text(argv[0]);
unsigned char const *zOld = sqlite3_value_text(argv[1]);
unsigned char const *zNew = sqlite3_value_text(argv[2]);
unsigned const char *z; /* Pointer to token */
int n; /* Length of token z */
int token; /* Type of token */
UNUSED_PARAMETER(NotUsed);
if( zInput==0 || zOld==0 ) return;
for(z=zInput; *z; z=z+n){
n = sqlite3GetToken(z, &token);
if( token==TK_REFERENCES ){
char *zParent;
do {
z += n;
n = sqlite3GetToken(z, &token);
}while( token==TK_SPACE );
if( token==TK_ILLEGAL ) break;
zParent = sqlite3DbStrNDup(db, (const char *)z, n);
if( zParent==0 ) break;
sqlite3Dequote(zParent);
if( 0==sqlite3StrICmp((const char *)zOld, zParent) ){
char *zOut = sqlite3MPrintf(db, "%s%.*s\"%w\"",
(zOutput?zOutput:""), (int)(z-zInput), zInput, (const char *)zNew
);
sqlite3DbFree(db, zOutput);
zOutput = zOut;
zInput = &z[n];
}
sqlite3DbFree(db, zParent);
}
}
zResult = sqlite3MPrintf(db, "%s%s", (zOutput?zOutput:""), zInput),
sqlite3_result_text(context, zResult, -1, SQLITE_DYNAMIC);
sqlite3DbFree(db, zOutput);
}
/*
** Invoke the 'collation needed' callback to request a collation sequence
** in the database text encoding of name zName, length nName.
** If the collation sequence
*/
static void callCollNeeded(sqlite3 *db, const char *zName, int nName){
assert( !db->xCollNeeded || !db->xCollNeeded16 );
if( nName<0 ) nName = sqlite3Strlen(db, zName);
if( db->xCollNeeded ){
char *zExternal = sqlite3DbStrNDup(db, zName, nName);
if( !zExternal ) return;
db->xCollNeeded(db->pCollNeededArg, db, (int)ENC(db), zExternal);
sqlite3DbFree(db, zExternal);
}
#ifndef SQLITE_OMIT_UTF16
if( db->xCollNeeded16 ){
char const *zExternal;
sqlite3_value *pTmp = sqlite3ValueNew(db);
sqlite3ValueSetStr(pTmp, nName, zName, SQLITE_UTF8, SQLITE_STATIC);
zExternal = sqlite3ValueText(pTmp, SQLITE_UTF16NATIVE);
if( zExternal ){
db->xCollNeeded16(db->pCollNeededArg, db, (int)ENC(db), zExternal);
}
sqlite3ValueFree(pTmp);
}
#endif
}
/*
** Run the parser on the given SQL string. The parser structure is
** passed in. An SQLITE_ status code is returned. If an error occurs
** then an and attempt is made to write an error message into
** memory obtained from sqlite3_malloc() and to make *pzErrMsg point to that
** error message.
*/
int sqlite3RunParser(Parse *pParse, const char *zSql, char **pzErrMsg){
int nErr = 0; /* Number of errors encountered */
void *pEngine; /* The LEMON-generated LALR(1) parser */
int n = 0; /* Length of the next token token */
int tokenType; /* type of the next token */
int lastTokenParsed = -1; /* type of the previous token */
sqlite3 *db = pParse->db; /* The database connection */
int mxSqlLen; /* Max length of an SQL string */
#ifdef sqlite3Parser_ENGINEALWAYSONSTACK
yyParser sEngine; /* Space to hold the Lemon-generated Parser object */
#endif
assert( zSql!=0 );
mxSqlLen = db->aLimit[SQLITE_LIMIT_SQL_LENGTH];
if( db->nVdbeActive==0 ){
db->u1.isInterrupted = 0;
}
pParse->rc = SQLITE_OK;
pParse->zTail = zSql;
assert( pzErrMsg!=0 );
#ifdef SQLITE_DEBUG
if( db->flags & SQLITE_ParserTrace ){
printf("parser: [[[%s]]]\n", zSql);
sqlite3ParserTrace(stdout, "parser: ");
}else{
sqlite3ParserTrace(0, 0);
}
#endif
#ifdef sqlite3Parser_ENGINEALWAYSONSTACK
pEngine = &sEngine;
sqlite3ParserInit(pEngine, pParse);
#else
pEngine = sqlite3ParserAlloc(sqlite3Malloc, pParse);
if( pEngine==0 ){
sqlite3OomFault(db);
return SQLITE_NOMEM_BKPT;
}
#endif
assert( pParse->pNewTable==0 );
assert( pParse->pNewTrigger==0 );
assert( pParse->nVar==0 );
assert( pParse->pVList==0 );
while( 1 ){
n = sqlite3GetToken((u8*)zSql, &tokenType);
mxSqlLen -= n;
if( mxSqlLen<0 ){
pParse->rc = SQLITE_TOOBIG;
break;
}
#ifndef SQLITE_OMIT_WINDOWFUNC
if( tokenType>=TK_WINDOW ){
assert( tokenType==TK_SPACE || tokenType==TK_OVER || tokenType==TK_FILTER
|| tokenType==TK_ILLEGAL || tokenType==TK_WINDOW
);
#else
if( tokenType>=TK_SPACE ){
assert( tokenType==TK_SPACE || tokenType==TK_ILLEGAL );
#endif /* SQLITE_OMIT_WINDOWFUNC */
if( db->u1.isInterrupted ){
pParse->rc = SQLITE_INTERRUPT;
break;
}
if( tokenType==TK_SPACE ){
zSql += n;
continue;
}
if( zSql[0]==0 ){
/* Upon reaching the end of input, call the parser two more times
** with tokens TK_SEMI and 0, in that order. */
if( lastTokenParsed==TK_SEMI ){
tokenType = 0;
}else if( lastTokenParsed==0 ){
break;
}else{
tokenType = TK_SEMI;
}
n = 0;
#ifndef SQLITE_OMIT_WINDOWFUNC
}else if( tokenType==TK_WINDOW ){
assert( n==6 );
tokenType = analyzeWindowKeyword((const u8*)&zSql[6]);
}else if( tokenType==TK_OVER ){
assert( n==4 );
tokenType = analyzeOverKeyword((const u8*)&zSql[4], lastTokenParsed);
}else if( tokenType==TK_FILTER ){
assert( n==6 );
tokenType = analyzeFilterKeyword((const u8*)&zSql[6], lastTokenParsed);
#endif /* SQLITE_OMIT_WINDOWFUNC */
}else{
sqlite3ErrorMsg(pParse, "unrecognized token: \"%.*s\"", n, zSql);
break;
}
}
pParse->sLastToken.z = zSql;
pParse->sLastToken.n = n;
sqlite3Parser(pEngine, tokenType, pParse->sLastToken);
lastTokenParsed = tokenType;
zSql += n;
if( pParse->rc!=SQLITE_OK || db->mallocFailed ) break;
}
assert( nErr==0 );
#ifdef YYTRACKMAXSTACKDEPTH
sqlite3_mutex_enter(sqlite3MallocMutex());
sqlite3StatusHighwater(SQLITE_STATUS_PARSER_STACK,
sqlite3ParserStackPeak(pEngine)
);
sqlite3_mutex_leave(sqlite3MallocMutex());
#endif /* YYDEBUG */
#ifdef sqlite3Parser_ENGINEALWAYSONSTACK
sqlite3ParserFinalize(pEngine);
#else
sqlite3ParserFree(pEngine, sqlite3_free);
#endif
if( db->mallocFailed ){
pParse->rc = SQLITE_NOMEM_BKPT;
}
if( pParse->rc!=SQLITE_OK && pParse->rc!=SQLITE_DONE && pParse->zErrMsg==0 ){
pParse->zErrMsg = sqlite3MPrintf(db, "%s", sqlite3ErrStr(pParse->rc));
}
assert( pzErrMsg!=0 );
if( pParse->zErrMsg ){
*pzErrMsg = pParse->zErrMsg;
sqlite3_log(pParse->rc, "%s in \"%s\"",
*pzErrMsg, pParse->zTail);
pParse->zErrMsg = 0;
nErr++;
}
pParse->zTail = zSql;
if( pParse->pVdbe && pParse->nErr>0 && pParse->nested==0 ){
sqlite3VdbeDelete(pParse->pVdbe);
pParse->pVdbe = 0;
}
#ifndef SQLITE_OMIT_SHARED_CACHE
if( pParse->nested==0 ){
sqlite3DbFree(db, pParse->aTableLock);
pParse->aTableLock = 0;
pParse->nTableLock = 0;
}
#endif
#ifndef SQLITE_OMIT_VIRTUALTABLE
sqlite3_free(pParse->apVtabLock);
#endif
if( !IN_SPECIAL_PARSE ){
/* If the pParse->declareVtab flag is set, do not delete any table
** structure built up in pParse->pNewTable. The calling code (see vtab.c)
** will take responsibility for freeing the Table structure.
*/
sqlite3DeleteTable(db, pParse->pNewTable);
}
if( !IN_RENAME_OBJECT ){
sqlite3DeleteTrigger(db, pParse->pNewTrigger);
}
if( pParse->pWithToFree ) sqlite3WithDelete(db, pParse->pWithToFree);
sqlite3DbFree(db, pParse->pVList);
while( pParse->pAinc ){
AutoincInfo *p = pParse->pAinc;
pParse->pAinc = p->pNext;
sqlite3DbFreeNN(db, p);
}
while( pParse->pZombieTab ){
Table *p = pParse->pZombieTab;
pParse->pZombieTab = p->pNextZombie;
sqlite3DeleteTable(db, p);
}
assert( nErr==0 || pParse->rc!=SQLITE_OK );
return nErr;
}
#ifdef SQLITE_ENABLE_NORMALIZE
/*
** Insert a single space character into pStr if the current string
** ends with an identifier
*/
static void addSpaceSeparator(sqlite3_str *pStr){
if( pStr->nChar && sqlite3IsIdChar(pStr->zText[pStr->nChar-1]) ){
sqlite3_str_append(pStr, " ", 1);
}
}
/*
** Compute a normalization of the SQL given by zSql[0..nSql-1]. Return
** the normalization in space obtained from sqlite3DbMalloc(). Or return
** NULL if anything goes wrong or if zSql is NULL.
*/
char *sqlite3Normalize(
Vdbe *pVdbe, /* VM being reprepared */
const char *zSql /* The original SQL string */
){
sqlite3 *db; /* The database connection */
int i; /* Next unread byte of zSql[] */
int n; /* length of current token */
int tokenType; /* type of current token */
int prevType = 0; /* Previous non-whitespace token */
int nParen; /* Number of nested levels of parentheses */
int iStartIN; /* Start of RHS of IN operator in z[] */
int nParenAtIN; /* Value of nParent at start of RHS of IN operator */
int j; /* Bytes of normalized SQL generated so far */
sqlite3_str *pStr; /* The normalized SQL string under construction */
db = sqlite3VdbeDb(pVdbe);
tokenType = -1;
nParen = iStartIN = nParenAtIN = 0;
pStr = sqlite3_str_new(db);
assert( pStr!=0 ); /* sqlite3_str_new() never returns NULL */
for(i=0; zSql[i] && pStr->accError==0; i+=n){
if( tokenType!=TK_SPACE ){
prevType = tokenType;
}
n = sqlite3GetToken((unsigned char*)zSql+i, &tokenType);
if( NEVER(n<=0) ) break;
switch( tokenType ){
case TK_SPACE: {
break;
}
case TK_NULL: {
if( prevType==TK_IS || prevType==TK_NOT ){
sqlite3_str_append(pStr, " NULL", 5);
break;
}
/* Fall through */
}
case TK_STRING:
case TK_INTEGER:
case TK_FLOAT:
case TK_VARIABLE:
case TK_BLOB: {
sqlite3_str_append(pStr, "?", 1);
break;
}
case TK_LP: {
nParen++;
if( prevType==TK_IN ){
iStartIN = pStr->nChar;
nParenAtIN = nParen;
}
sqlite3_str_append(pStr, "(", 1);
break;
}
case TK_RP: {
if( iStartIN>0 && nParen==nParenAtIN ){
assert( pStr->nChar>=iStartIN );
pStr->nChar = iStartIN+1;
sqlite3_str_append(pStr, "?,?,?", 5);
iStartIN = 0;
}
nParen--;
sqlite3_str_append(pStr, ")", 1);
break;
}
case TK_ID: {
iStartIN = 0;
j = pStr->nChar;
if( sqlite3Isquote(zSql[i]) ){
char *zId = sqlite3DbStrNDup(db, zSql+i, n);
int nId;
int eType = 0;
if( zId==0 ) break;
sqlite3Dequote(zId);
if( zSql[i]=='"' && sqlite3VdbeUsesDoubleQuotedString(pVdbe, zId) ){
sqlite3_str_append(pStr, "?", 1);
sqlite3DbFree(db, zId);
break;
}
nId = sqlite3Strlen30(zId);
if( sqlite3GetToken((u8*)zId, &eType)==nId && eType==TK_ID ){
addSpaceSeparator(pStr);
sqlite3_str_append(pStr, zId, nId);
}else{
sqlite3_str_appendf(pStr, "\"%w\"", zId);
}
sqlite3DbFree(db, zId);
}else{
addSpaceSeparator(pStr);
sqlite3_str_append(pStr, zSql+i, n);
}
while( j<pStr->nChar ){
pStr->zText[j] = sqlite3Tolower(pStr->zText[j]);
j++;
}
break;
}
case TK_SELECT: {
iStartIN = 0;
/* fall through */
}
default: {
if( sqlite3IsIdChar(zSql[i]) ) addSpaceSeparator(pStr);
j = pStr->nChar;
sqlite3_str_append(pStr, zSql+i, n);
while( j<pStr->nChar ){
pStr->zText[j] = sqlite3Toupper(pStr->zText[j]);
j++;
}
break;
}
}
}
if( tokenType!=TK_SEMI ) sqlite3_str_append(pStr, ";", 1);
return sqlite3_str_finish(pStr);
}
/*
** 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->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(db, pDflt, SQLITE_UTF8, SQLITE_AFF_NONE, &pVal) ){
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];
while( (zEnd>zCol && *zEnd==';') || sqlite3Isspace(*zEnd) ){
*zEnd-- = '\0';
}
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);
}
/* 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 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; */
Vdbe *v = pParse->pVdbe; /* The prepared statement under construction */
db = pParse->db;
if( pParse->nErr || db->mallocFailed ) return;
assert( v!=0 );
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 ){
assert( 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 the file
** format to 2. If the default value of the new column is not NULL,
** the file format be 3. Back when this feature was first added
** in 2006, we went to the trouble to upgrade the file format to the
** minimum support values. But 10-years on, we can assume that all
** extent versions of SQLite support file-format 4, so we always and
** unconditionally upgrade to 4.
*/
sqlite3VdbeAddOp3(v, OP_SetCookie, iDb, BTREE_FILE_FORMAT,
SQLITE_MAX_FILE_FORMAT);
/* Reload the schema of the modified table. */
reloadTableSchema(pParse, pTab, pTab->zName);
}
/*
** Compile the UTF-8 encoded SQL statement zSql into a statement handle.
*/
static int sqlite3Prepare(
sqlite3 *db, /* Database handle. */
const char *zSql, /* UTF-8 encoded SQL statement. */
int nBytes, /* Length of zSql in bytes. */
int saveSqlFlag, /* True to copy SQL text into the sqlite3_stmt */
sqlite3_stmt **ppStmt, /* OUT: A pointer to the prepared statement */
const char **pzTail /* OUT: End of parsed string */
){
Parse sParse;
char *zErrMsg = 0;
int rc = SQLITE_OK;
int i;
assert( ppStmt );
*ppStmt = 0;
if( sqlite3SafetyOn(db) ){
return SQLITE_MISUSE;
}
assert( !db->mallocFailed );
assert( sqlite3_mutex_held(db->mutex) );
/* Check to verify that it is possible to get a read lock on all
** database schemas. The inability to get a read lock indicates that
** some other database connection is holding a write-lock, which in
** turn means that the other connection has made uncommitted changes
** to the schema.
**
** Were we to proceed and prepare the statement against the uncommitted
** schema changes and if those schema changes are subsequently rolled
** back and different changes are made in their place, then when this
** prepared statement goes to run the schema cookie would fail to detect
** the schema change. Disaster would follow.
**
** This thread is currently holding mutexes on all Btrees (because
** of the sqlite3BtreeEnterAll() in sqlite3LockAndPrepare()) so it
** is not possible for another thread to start a new schema change
** while this routine is running. Hence, we do not need to hold
** locks on the schema, we just need to make sure nobody else is
** holding them.
**
** Note that setting READ_UNCOMMITTED overrides most lock detection,
** but it does *not* override schema lock detection, so this all still
** works even if READ_UNCOMMITTED is set.
*/
for(i=0; i<db->nDb; i++) {
Btree *pBt = db->aDb[i].pBt;
if( pBt ){
assert( sqlite3BtreeHoldsMutex(pBt) );
rc = sqlite3BtreeSchemaLocked(pBt);
if( rc ){
const char *zDb = db->aDb[i].zName;
sqlite3Error(db, rc, "database schema is locked: %s", zDb);
(void)sqlite3SafetyOff(db);
testcase( db->flags & SQLITE_ReadUncommitted );
return sqlite3ApiExit(db, rc);
}
}
}
memset(&sParse, 0, sizeof(sParse));
sParse.db = db;
if( nBytes>=0 && (nBytes==0 || zSql[nBytes-1]!=0) ){
char *zSqlCopy;
int mxLen = db->aLimit[SQLITE_LIMIT_SQL_LENGTH];
if( nBytes>mxLen ){
sqlite3Error(db, SQLITE_TOOBIG, "statement too long");
(void)sqlite3SafetyOff(db);
return sqlite3ApiExit(db, SQLITE_TOOBIG);
}
zSqlCopy = sqlite3DbStrNDup(db, zSql, nBytes);
if( zSqlCopy ){
sqlite3RunParser(&sParse, zSqlCopy, &zErrMsg);
sqlite3DbFree(db, zSqlCopy);
sParse.zTail = &zSql[sParse.zTail-zSqlCopy];
}else{
sParse.zTail = &zSql[nBytes];
}
}else{
sqlite3RunParser(&sParse, zSql, &zErrMsg);
}
if( db->mallocFailed ){
sParse.rc = SQLITE_NOMEM;
}
if( sParse.rc==SQLITE_DONE ) sParse.rc = SQLITE_OK;
if( sParse.checkSchema && !schemaIsValid(db) ){
sParse.rc = SQLITE_SCHEMA;
}
if( sParse.rc==SQLITE_SCHEMA ){
sqlite3ResetInternalSchema(db, 0);
}
if( db->mallocFailed ){
sParse.rc = SQLITE_NOMEM;
}
if( pzTail ){
*pzTail = sParse.zTail;
}
rc = sParse.rc;
#ifndef SQLITE_OMIT_EXPLAIN
if( rc==SQLITE_OK && sParse.pVdbe && sParse.explain ){
if( sParse.explain==2 ){
sqlite3VdbeSetNumCols(sParse.pVdbe, 3);
sqlite3VdbeSetColName(sParse.pVdbe, 0, COLNAME_NAME, "order", SQLITE_STATIC);
sqlite3VdbeSetColName(sParse.pVdbe, 1, COLNAME_NAME, "from", SQLITE_STATIC);
sqlite3VdbeSetColName(sParse.pVdbe, 2, COLNAME_NAME, "detail", SQLITE_STATIC);
}else{
sqlite3VdbeSetNumCols(sParse.pVdbe, 8);
sqlite3VdbeSetColName(sParse.pVdbe, 0, COLNAME_NAME, "addr", SQLITE_STATIC);
sqlite3VdbeSetColName(sParse.pVdbe, 1, COLNAME_NAME, "opcode", SQLITE_STATIC);
sqlite3VdbeSetColName(sParse.pVdbe, 2, COLNAME_NAME, "p1", SQLITE_STATIC);
sqlite3VdbeSetColName(sParse.pVdbe, 3, COLNAME_NAME, "p2", SQLITE_STATIC);
sqlite3VdbeSetColName(sParse.pVdbe, 4, COLNAME_NAME, "p3", SQLITE_STATIC);
sqlite3VdbeSetColName(sParse.pVdbe, 5, COLNAME_NAME, "p4", SQLITE_STATIC);
sqlite3VdbeSetColName(sParse.pVdbe, 6, COLNAME_NAME, "p5", SQLITE_STATIC);
sqlite3VdbeSetColName(sParse.pVdbe, 7, COLNAME_NAME, "comment", SQLITE_STATIC);
}
}
#endif
if( sqlite3SafetyOff(db) ){
rc = SQLITE_MISUSE;
}
assert( db->init.busy==0 || saveSqlFlag==0 );
if( db->init.busy==0 ){
Vdbe *pVdbe = sParse.pVdbe;
sqlite3VdbeSetSql(pVdbe, zSql, (int)(sParse.zTail-zSql), saveSqlFlag);
}
if( sParse.pVdbe && (rc!=SQLITE_OK || db->mallocFailed) ){
sqlite3VdbeFinalize(sParse.pVdbe);
assert(!(*ppStmt));
}else{
*ppStmt = (sqlite3_stmt*)sParse.pVdbe;
}
if( zErrMsg ){
sqlite3Error(db, rc, "%s", zErrMsg);
sqlite3DbFree(db, zErrMsg);
}else{
sqlite3Error(db, rc, 0);
}
rc = sqlite3ApiExit(db, rc);
assert( (rc&db->errMask)==rc );
return rc;
}
/*
** This routine is called after all of the trigger actions have been parsed
** in order to complete the process of building the trigger.
*/
SQLITE_PRIVATE 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);
}
/*
** Compile the UTF-8 encoded SQL statement zSql into a statement handle.
*/
static int sqlite3Prepare(
sqlite3 *db, /* Database handle. */
const char *zSql, /* UTF-8 encoded SQL statement. */
int nBytes, /* Length of zSql in bytes. */
int saveSqlFlag, /* True to copy SQL text into the sqlite3_stmt */
Vdbe *pReprepare, /* VM being reprepared */
sqlite3_stmt **ppStmt, /* OUT: A pointer to the prepared statement */
const char **pzTail /* OUT: End of parsed string */
){
Parse *pParse; /* Parsing context */
char *zErrMsg = 0; /* Error message */
int rc = SQLITE_OK; /* Result code */
int i; /* Loop counter */
/* Allocate the parsing context */
pParse = sqlite3StackAllocZero(db, sizeof(*pParse));
if( pParse==0 ){
rc = SQLITE_NOMEM;
goto end_prepare;
}
pParse->pReprepare = pReprepare;
if( sqlite3SafetyOn(db) ){
rc = SQLITE_MISUSE;
goto end_prepare;
}
assert( ppStmt && *ppStmt==0 );
assert( !db->mallocFailed );
assert( sqlite3_mutex_held(db->mutex) );
/* Check to verify that it is possible to get a read lock on all
** database schemas. The inability to get a read lock indicates that
** some other database connection is holding a write-lock, which in
** turn means that the other connection has made uncommitted changes
** to the schema.
**
** Were we to proceed and prepare the statement against the uncommitted
** schema changes and if those schema changes are subsequently rolled
** back and different changes are made in their place, then when this
** prepared statement goes to run the schema cookie would fail to detect
** the schema change. Disaster would follow.
**
** This thread is currently holding mutexes on all Btrees (because
** of the sqlite3BtreeEnterAll() in sqlite3LockAndPrepare()) so it
** is not possible for another thread to start a new schema change
** while this routine is running. Hence, we do not need to hold
** locks on the schema, we just need to make sure nobody else is
** holding them.
**
** Note that setting READ_UNCOMMITTED overrides most lock detection,
** but it does *not* override schema lock detection, so this all still
** works even if READ_UNCOMMITTED is set.
*/
for(i=0; i<db->nDb; i++) {
Btree *pBt = db->aDb[i].pBt;
if( pBt ){
assert( sqlite3BtreeHoldsMutex(pBt) );
rc = sqlite3BtreeSchemaLocked(pBt);
if( rc ){
const char *zDb = db->aDb[i].zName;
sqlite3Error(db, rc, "database schema is locked: %s", zDb);
(void)sqlite3SafetyOff(db);
testcase( db->flags & SQLITE_ReadUncommitted );
goto end_prepare;
}
}
}
sqlite3VtabUnlockList(db);
pParse->db = db;
if( nBytes>=0 && (nBytes==0 || zSql[nBytes-1]!=0) ){
char *zSqlCopy;
int mxLen = db->aLimit[SQLITE_LIMIT_SQL_LENGTH];
testcase( nBytes==mxLen );
testcase( nBytes==mxLen+1 );
if( nBytes>mxLen ){
sqlite3Error(db, SQLITE_TOOBIG, "statement too long");
(void)sqlite3SafetyOff(db);
rc = sqlite3ApiExit(db, SQLITE_TOOBIG);
goto end_prepare;
}
zSqlCopy = sqlite3DbStrNDup(db, zSql, nBytes);
if( zSqlCopy ){
sqlite3RunParser(pParse, zSqlCopy, &zErrMsg);
sqlite3DbFree(db, zSqlCopy);
pParse->zTail = &zSql[pParse->zTail-zSqlCopy];
}else{
pParse->zTail = &zSql[nBytes];
}
}else{
sqlite3RunParser(pParse, zSql, &zErrMsg);
}
if( db->mallocFailed ){
pParse->rc = SQLITE_NOMEM;
}
if( pParse->rc==SQLITE_DONE ) pParse->rc = SQLITE_OK;
if( pParse->checkSchema ){
schemaIsValid(pParse);
}
if( pParse->rc==SQLITE_SCHEMA ){
sqlite3ResetInternalSchema(db, 0);
}
if( db->mallocFailed ){
pParse->rc = SQLITE_NOMEM;
}
if( pzTail ){
*pzTail = pParse->zTail;
}
rc = pParse->rc;
#ifndef SQLITE_OMIT_EXPLAIN
if( rc==SQLITE_OK && pParse->pVdbe && pParse->explain ){
static const char * const azColName[] = {
"addr", "opcode", "p1", "p2", "p3", "p4", "p5", "comment",
"order", "from", "detail"
};
int iFirst, mx;
if( pParse->explain==2 ){
sqlite3VdbeSetNumCols(pParse->pVdbe, 3);
iFirst = 8;
mx = 11;
}else{
sqlite3VdbeSetNumCols(pParse->pVdbe, 8);
iFirst = 0;
mx = 8;
}
for(i=iFirst; i<mx; i++){
sqlite3VdbeSetColName(pParse->pVdbe, i-iFirst, COLNAME_NAME,
azColName[i], SQLITE_STATIC);
}
}
#endif
if( sqlite3SafetyOff(db) ){
rc = SQLITE_MISUSE;
}
assert( db->init.busy==0 || saveSqlFlag==0 );
if( db->init.busy==0 ){
Vdbe *pVdbe = pParse->pVdbe;
sqlite3VdbeSetSql(pVdbe, zSql, (int)(pParse->zTail-zSql), saveSqlFlag);
}
if( pParse->pVdbe && (rc!=SQLITE_OK || db->mallocFailed) ){
sqlite3VdbeFinalize(pParse->pVdbe);
assert(!(*ppStmt));
}else{
*ppStmt = (sqlite3_stmt*)pParse->pVdbe;
}
if( zErrMsg ){
sqlite3Error(db, rc, "%s", zErrMsg);
sqlite3DbFree(db, zErrMsg);
}else{
sqlite3Error(db, rc, 0);
}
/* Delete any TriggerPrg structures allocated while parsing this statement. */
while( pParse->pTriggerPrg ){
TriggerPrg *pT = pParse->pTriggerPrg;
pParse->pTriggerPrg = pT->pNext;
sqlite3VdbeProgramDelete(db, pT->pProgram, 0);
sqlite3DbFree(db, pT);
}
end_prepare:
sqlite3StackFree(db, pParse);
rc = sqlite3ApiExit(db, rc);
assert( (rc&db->errMask)==rc );
return rc;
}
/*
** Load the content of the sqlite_stat1 and sqlite_stat2 tables. The
** contents of sqlite_stat1 are used to populate the Index.aiRowEst[]
** arrays. The contents of sqlite_stat2 are used to populate the
** Index.aSample[] arrays.
**
** If the sqlite_stat1 table is not present in the database, SQLITE_ERROR
** is returned. In this case, even if SQLITE_ENABLE_STAT2 was defined
** during compilation and the sqlite_stat2 table is present, no data is
** read from it.
**
** If SQLITE_ENABLE_STAT2 was defined during compilation and the
** sqlite_stat2 table is not present in the database, SQLITE_ERROR is
** returned. However, in this case, data is read from the sqlite_stat1
** table (if it is present) before returning.
**
** If an OOM error occurs, this function always sets db->mallocFailed.
** This means if the caller does not care about other errors, the return
** code may be ignored.
*/
int sqlite3AnalysisLoad(sqlite3 *db, int iDb){
analysisInfo sInfo;
HashElem *i;
char *zSql;
int rc;
assert( iDb>=0 && iDb<db->nDb );
assert( db->aDb[iDb].pBt!=0 );
/* Clear any prior statistics */
assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
for(i=sqliteHashFirst(&db->aDb[iDb].pSchema->idxHash);i;i=sqliteHashNext(i)){
Index *pIdx = (Index *) sqliteHashData(i);
sqlite3DefaultRowEst(pIdx);
sqlite3DeleteIndexSamples(db, pIdx);
pIdx->aSample = 0;
}
/* Check to make sure the sqlite_stat1 table exists */
sInfo.db = db;
sInfo.zDatabase = db->aDb[iDb].zName;
if( sqlite3FindTable(db, "sqlite_stat1", sInfo.zDatabase)==0 ){
return SQLITE_ERROR;
}
/* Load new statistics out of the sqlite_stat1 table */
zSql = sqlite3MPrintf(db,
"SELECT tbl, idx, stat FROM %Q.sqlite_stat1", sInfo.zDatabase);
if( zSql==0 ){
rc = SQLITE_NOMEM;
}else{
rc = sqlite3_exec(db, zSql, analysisLoader, &sInfo, 0);
sqlite3DbFree(db, zSql);
}
/* Load the statistics from the sqlite_stat2 table. */
#ifdef SQLITE_ENABLE_STAT2
if( rc==SQLITE_OK && !sqlite3FindTable(db, "sqlite_stat2", sInfo.zDatabase) ){
rc = SQLITE_ERROR;
}
if( rc==SQLITE_OK ){
sqlite3_stmt *pStmt = 0;
zSql = sqlite3MPrintf(db,
"SELECT idx,sampleno,sample FROM %Q.sqlite_stat2", sInfo.zDatabase);
if( !zSql ){
rc = SQLITE_NOMEM;
}else{
rc = sqlite3_prepare(db, zSql, -1, &pStmt, 0);
sqlite3DbFree(db, zSql);
}
if( rc==SQLITE_OK ){
while( sqlite3_step(pStmt)==SQLITE_ROW ){
char *zIndex; /* Index name */
Index *pIdx; /* Pointer to the index object */
zIndex = (char *)sqlite3_column_text(pStmt, 0);
pIdx = zIndex ? sqlite3FindIndex(db, zIndex, sInfo.zDatabase) : 0;
if( pIdx ){
int iSample = sqlite3_column_int(pStmt, 1);
if( iSample<SQLITE_INDEX_SAMPLES && iSample>=0 ){
int eType = sqlite3_column_type(pStmt, 2);
if( pIdx->aSample==0 ){
static const int sz = sizeof(IndexSample)*SQLITE_INDEX_SAMPLES;
pIdx->aSample = (IndexSample *)sqlite3DbMallocRaw(0, sz);
if( pIdx->aSample==0 ){
db->mallocFailed = 1;
break;
}
memset(pIdx->aSample, 0, sz);
}
assert( pIdx->aSample );
{
IndexSample *pSample = &pIdx->aSample[iSample];
pSample->eType = (u8)eType;
if( eType==SQLITE_INTEGER || eType==SQLITE_FLOAT ){
pSample->u.r = sqlite3_column_double(pStmt, 2);
}else if( eType==SQLITE_TEXT || eType==SQLITE_BLOB ){
const char *z = (const char *)(
(eType==SQLITE_BLOB) ?
sqlite3_column_blob(pStmt, 2):
sqlite3_column_text(pStmt, 2)
);
int n = sqlite3_column_bytes(pStmt, 2);
if( n>24 ){
n = 24;
}
pSample->nByte = (u8)n;
if( n < 1){
pSample->u.z = 0;
}else{
pSample->u.z = sqlite3DbStrNDup(0, z, n);
if( pSample->u.z==0 ){
db->mallocFailed = 1;
break;
}
}
}
}
}
}
}
rc = sqlite3_finalize(pStmt);
}
}
#endif
if( rc==SQLITE_NOMEM ){
db->mallocFailed = 1;
}
return rc;
}
/*
** 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 = 0; /* The trigger whose construction is finishing up */
sqlite3 *db = pParse->db; /* The database */
DbFixer sFix;
int iDb; /* Database containing the trigger */
pTrig = pParse->pNewTrigger;
pParse->pNewTrigger = 0;
if( pParse->nErr || !pTrig ) goto triggerfinish_cleanup;
iDb = sqlite3SchemaToIndex(pParse->db, pTrig->pSchema);
pTrig->step_list = pStepList;
while( pStepList ){
pStepList->pTrig = pTrig;
pStepList = pStepList->pNext;
}
if( sqlite3FixInit(&sFix, pParse, iDb, "trigger", &pTrig->nameToken)
&& sqlite3FixTriggerStep(&sFix, pTrig->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 ){
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), pTrig->name,
pTrig->table, z);
sqlite3DbFree(db, z);
sqlite3ChangeCookie(pParse, iDb);
sqlite3VdbeAddOp4(v, OP_ParseSchema, iDb, 0, 0, sqlite3MPrintf(
db, "type='trigger' AND name='%q'", pTrig->name), P4_DYNAMIC
);
}
if( db->init.busy ){
int n;
Table *pTab;
Trigger *pDel;
pDel = sqlite3HashInsert(&db->aDb[iDb].pSchema->trigHash,
pTrig->name, sqlite3Strlen30(pTrig->name), pTrig);
if( pDel ){
assert( pDel==pTrig );
db->mallocFailed = 1;
goto triggerfinish_cleanup;
}
n = sqlite3Strlen30(pTrig->table) + 1;
pTab = sqlite3HashFind(&pTrig->pTabSchema->tblHash, pTrig->table, n);
assert( pTab!=0 );
pTrig->pNext = pTab->pTrigger;
pTab->pTrigger = pTrig;
pTrig = 0;
}
triggerfinish_cleanup:
sqlite3DeleteTrigger(db, pTrig);
assert( !pParse->pNewTrigger );
sqlite3DeleteTriggerStep(db, pStepList);
}
/*
** 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.
在“ALTER TABLE…添加“声明解析后这个函数被调用。
参数pColDef包含新列定义的文本。
表结构pParse - > pNewTable扩大到包括在解析新列。
*/
void sqlite3AlterFinishAddColumn(Parse *pParse, Token *pColDef){
Table *pNew; /* Copy of pParse->pNewTable pParse->pNew表的副本*/
Table *pTab; /* Table being altered 被修改的表*/
int iDb; /* Database number 数据库数*/
const char *zDb; /* Database name 数据库名*/
const char *zTab; /* Table name 表名*/
char *zCol; /* Null-terminated column definition 空值终止列定义*/
Column *pCol; /* The new column 新列*/
Expr *pDflt; /* Default value for the new column 为新列默认数值*/
sqlite3 *db; /* The database connection; 数据库的连接*/
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 跳过“sqlite_altertab_”前缀的名称*/
pCol = &pNew->aCol[pNew->nCol-1];
pDflt = pCol->pDflt;
pTab = sqlite3FindTable(db, zTab, zDb);
assert( pTab );
#ifndef SQLITE_OMIT_AUTHORIZATION
/* Invoke the authorization callback. 调用授权回调*/
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.
如果新列的默认值是用文字指定NULL,那么pDflt设置为0。
这简化了检查SQL空下面的默认。
*/
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.
检查新列没有指定主键或唯一的。
如果有一个非空约束,然后列的默认值不能为空。
*/
if( pCol->isPrimKey ){
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.)
确保默认表达式是sqlite3ValueFromExpr()可以处理的事(即不是当前时间等。)
*/
if( pDflt ){
sqlite3_value *pVal;
if( sqlite3ValueFromExpr(db, pDflt, SQLITE_UTF8, SQLITE_AFF_NONE, &pVal) ){
db->mallocFailed = 1;
return;
}
if( !pVal ){
sqlite3ErrorMsg(pParse, "Cannot add a column with non-constant default");
return;
}
sqlite3ValueFree(pVal);
}
/* Modify the CREATE TABLE statement. 修改CREATE TABLE语句。*/
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.
如果新列的默认值为空,那么将文件格式设置为2。如果新列的默认值不为空,文件格式变成3。
*/
sqlite3MinimumFileFormat(pParse, iDb, pDflt ? 3 : 2);
/* Reload the schema of the modified table. 重新加载修改后的表的模式。*/
reloadTableSchema(pParse, pTab, pTab->zName);
}