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-rw-r--r--src/vdbe.c99
1 files changed, 38 insertions, 61 deletions
diff --git a/src/vdbe.c b/src/vdbe.c
index 037b02f12..7c8cfe13d 100644
--- a/src/vdbe.c
+++ b/src/vdbe.c
@@ -2946,7 +2946,7 @@ case OP_AutoCommit: {
break;
}
-/* Opcode: Transaction P1 P2 * * *
+/* Opcode: Transaction P1 P2 P3 P4 P5
**
** Begin a transaction. The transaction ends when a Commit or Rollback
** opcode is encountered. Depending on the ON CONFLICT setting, the
@@ -2976,9 +2976,17 @@ case OP_AutoCommit: {
** will automatically commit when the VDBE halts.
**
** If P2 is zero, then a read-lock is obtained on the database file.
+**
+** If P5!=0 then this opcode also checks the schema cookie against P3
+** and the schema generation counter against P4.
+** The cookie changes its value whenever the database schema changes.
+** This operation is used to detect when that the cookie has changed
+** and that the current process needs to reread the schema.
*/
case OP_Transaction: {
Btree *pBt;
+ int iMeta;
+ int iGen;
assert( p->bIsReader );
assert( p->readOnly==0 || pOp->p2==0 );
@@ -3022,6 +3030,35 @@ case OP_Transaction: {
p->nStmtDefCons = db->nDeferredCons;
p->nStmtDefImmCons = db->nDeferredImmCons;
}
+
+ /* Gather the schema version number for checking */
+ sqlite3BtreeGetMeta(pBt, BTREE_SCHEMA_VERSION, (u32 *)&iMeta);
+ iGen = db->aDb[pOp->p1].pSchema->iGeneration;
+ }else{
+ iGen = iMeta = 0;
+ }
+ assert( pOp->p5==0 || pOp->p4type==P4_INT32 );
+ if( pOp->p5 && (iMeta!=pOp->p3 || iGen!=pOp->p4.i) ){
+ sqlite3DbFree(db, p->zErrMsg);
+ p->zErrMsg = sqlite3DbStrDup(db, "database schema has changed");
+ /* If the schema-cookie from the database file matches the cookie
+ ** stored with the in-memory representation of the schema, do
+ ** not reload the schema from the database file.
+ **
+ ** If virtual-tables are in use, this is not just an optimization.
+ ** Often, v-tables store their data in other SQLite tables, which
+ ** are queried from within xNext() and other v-table methods using
+ ** prepared queries. If such a query is out-of-date, we do not want to
+ ** discard the database schema, as the user code implementing the
+ ** v-table would have to be ready for the sqlite3_vtab structure itself
+ ** to be invalidated whenever sqlite3_step() is called from within
+ ** a v-table method.
+ */
+ if( db->aDb[pOp->p1].pSchema->schema_cookie!=iMeta ){
+ sqlite3ResetOneSchema(db, pOp->p1);
+ }
+ p->expired = 1;
+ rc = SQLITE_SCHEMA;
}
break;
}
@@ -3096,66 +3133,6 @@ case OP_SetCookie: { /* in3 */
break;
}
-/* Opcode: VerifyCookie P1 P2 P3 * *
-**
-** Check the value of global database parameter number 0 (the
-** schema version) and make sure it is equal to P2 and that the
-** generation counter on the local schema parse equals P3.
-**
-** P1 is the database number which is 0 for the main database file
-** and 1 for the file holding temporary tables and some higher number
-** for auxiliary databases.
-**
-** The cookie changes its value whenever the database schema changes.
-** This operation is used to detect when that the cookie has changed
-** and that the current process needs to reread the schema.
-**
-** Either a transaction needs to have been started or an OP_Open needs
-** to be executed (to establish a read lock) before this opcode is
-** invoked.
-*/
-case OP_VerifyCookie: {
- int iMeta;
- int iGen;
- Btree *pBt;
-
- assert( pOp->p1>=0 && pOp->p1<db->nDb );
- assert( (p->btreeMask & (((yDbMask)1)<<pOp->p1))!=0 );
- assert( sqlite3SchemaMutexHeld(db, pOp->p1, 0) );
- assert( p->bIsReader );
- pBt = db->aDb[pOp->p1].pBt;
- if( pBt ){
- sqlite3BtreeGetMeta(pBt, BTREE_SCHEMA_VERSION, (u32 *)&iMeta);
- iGen = db->aDb[pOp->p1].pSchema->iGeneration;
- }else{
- iGen = iMeta = 0;
- }
- if( iMeta!=pOp->p2 || iGen!=pOp->p3 ){
- sqlite3DbFree(db, p->zErrMsg);
- p->zErrMsg = sqlite3DbStrDup(db, "database schema has changed");
- /* If the schema-cookie from the database file matches the cookie
- ** stored with the in-memory representation of the schema, do
- ** not reload the schema from the database file.
- **
- ** If virtual-tables are in use, this is not just an optimization.
- ** Often, v-tables store their data in other SQLite tables, which
- ** are queried from within xNext() and other v-table methods using
- ** prepared queries. If such a query is out-of-date, we do not want to
- ** discard the database schema, as the user code implementing the
- ** v-table would have to be ready for the sqlite3_vtab structure itself
- ** to be invalidated whenever sqlite3_step() is called from within
- ** a v-table method.
- */
- if( db->aDb[pOp->p1].pSchema->schema_cookie!=iMeta ){
- sqlite3ResetOneSchema(db, pOp->p1);
- }
-
- p->expired = 1;
- rc = SQLITE_SCHEMA;
- }
- break;
-}
-
/* Opcode: OpenRead P1 P2 P3 P4 P5
** Synopsis: root=P2 iDb=P3
**