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Diffstat (limited to 'src/delete.c')
-rw-r--r--src/delete.c435
1 files changed, 310 insertions, 125 deletions
diff --git a/src/delete.c b/src/delete.c
index 634e115..c74d8ea 100644
--- a/src/delete.c
+++ b/src/delete.c
@@ -97,10 +97,8 @@ void sqlite3MaterializeView(
SrcList *pFrom;
sqlite3 *db = pParse->db;
int iDb = sqlite3SchemaToIndex(db, pView->pSchema);
-
pWhere = sqlite3ExprDup(db, pWhere, 0);
pFrom = sqlite3SrcListAppend(db, 0, 0, 0);
-
if( pFrom ){
assert( pFrom->nSrc==1 );
pFrom->a[0].zName = sqlite3DbStrDup(db, pView->zName);
@@ -108,10 +106,7 @@ void sqlite3MaterializeView(
assert( pFrom->a[0].pOn==0 );
assert( pFrom->a[0].pUsing==0 );
}
-
pSel = sqlite3SelectNew(pParse, 0, pFrom, pWhere, 0, 0, 0, 0, 0, 0);
- if( pSel ) pSel->selFlags |= SF_Materialize;
-
sqlite3SelectDestInit(&dest, SRT_EphemTab, iCur);
sqlite3Select(pParse, pSel, &dest);
sqlite3SelectDelete(db, pSel);
@@ -134,7 +129,7 @@ Expr *sqlite3LimitWhere(
ExprList *pOrderBy, /* The ORDER BY clause. May be null */
Expr *pLimit, /* The LIMIT clause. May be null */
Expr *pOffset, /* The OFFSET clause. May be null */
- char *zStmtType /* Either DELETE or UPDATE. For error messages. */
+ char *zStmtType /* Either DELETE or UPDATE. For err msgs. */
){
Expr *pWhereRowid = NULL; /* WHERE rowid .. */
Expr *pInClause = NULL; /* WHERE rowid IN ( select ) */
@@ -209,7 +204,8 @@ limit_where_cleanup_2:
sqlite3ExprDelete(pParse->db, pOffset);
return 0;
}
-#endif /* defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY) */
+#endif /* defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) */
+ /* && !defined(SQLITE_OMIT_SUBQUERY) */
/*
** Generate code for a DELETE FROM statement.
@@ -226,18 +222,34 @@ void sqlite3DeleteFrom(
Vdbe *v; /* The virtual database engine */
Table *pTab; /* The table from which records will be deleted */
const char *zDb; /* Name of database holding pTab */
- int end, addr = 0; /* A couple addresses of generated code */
int i; /* Loop counter */
WhereInfo *pWInfo; /* Information about the WHERE clause */
Index *pIdx; /* For looping over indices of the table */
- int iCur; /* VDBE Cursor number for pTab */
+ int iTabCur; /* Cursor number for the table */
+ int iDataCur; /* VDBE cursor for the canonical data source */
+ int iIdxCur; /* 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 okOnePass; /* True for one-pass algorithm without the FIFO */
+ 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 addrDelete = 0; /* Jump directly to the delete logic */
+ int addrEphOpen = 0; /* Instruction to open the Ephermeral table */
+
#ifndef SQLITE_OMIT_TRIGGER
int isView; /* True if attempting to delete from a view */
Trigger *pTrigger; /* List of table triggers, if required */
@@ -292,11 +304,11 @@ void sqlite3DeleteFrom(
}
assert(!isView || pTrigger);
- /* Assign cursor number to the table and all its indices.
+ /* Assign cursor numbers to the table and all its indices.
*/
assert( pTabList->nSrc==1 );
- iCur = pTabList->a[0].iCursor = pParse->nTab++;
- for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
+ iTabCur = pTabList->a[0].iCursor = pParse->nTab++;
+ for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){
pParse->nTab++;
}
@@ -320,7 +332,8 @@ void sqlite3DeleteFrom(
*/
#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
if( isView ){
- sqlite3MaterializeView(pParse, pTab, pWhere, iCur);
+ sqlite3MaterializeView(pParse, pTab, pWhere, iTabCur);
+ iDataCur = iIdxCur = iTabCur;
}
#endif
@@ -350,78 +363,171 @@ void sqlite3DeleteFrom(
&& 0==sqlite3FkRequired(pParse, pTab, 0, 0)
){
assert( !isView );
- sqlite3VdbeAddOp4(v, OP_Clear, pTab->tnum, iDb, memCnt,
- pTab->zName, P4_STATIC);
+ 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 */
- /* The usual case: There is a WHERE clause so we have to scan through
- ** the table and pick which records to delete.
- */
{
- int iRowSet = ++pParse->nMem; /* Register for rowset of rows to delete */
- int iRowid = ++pParse->nMem; /* Used for storing rowid values. */
- int regRowid; /* Actual register containing rowids */
-
- /* Collect rowids of every row to be deleted.
+ 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 ephermeral 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.
*/
- sqlite3VdbeAddOp2(v, OP_Null, 0, iRowSet);
- pWInfo = sqlite3WhereBegin(
- pParse, pTabList, pWhere, 0, 0, WHERE_DUPLICATES_OK, 0
- );
+ pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0, 0,
+ WHERE_ONEPASS_DESIRED|WHERE_DUPLICATES_OK,
+ iTabCur+1);
if( pWInfo==0 ) goto delete_from_cleanup;
- regRowid = sqlite3ExprCodeGetColumn(pParse, pTab, -1, iCur, iRowid, 0);
- sqlite3VdbeAddOp2(v, OP_RowSetAdd, iRowSet, regRowid);
+ okOnePass = sqlite3WhereOkOnePass(pWInfo, aiCurOnePass);
+
+ /* 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++){
+ 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( okOnePass ){
+ /* 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 = sqlite3DbMallocRaw(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);
+ addrDelete = sqlite3VdbeAddOp0(v, OP_Goto); /* Jump to DELETE logic */
+ }else if( pPk ){
+ /* Construct a composite key for the row to be deleted and remember it */
+ iKey = ++pParse->nMem;
+ nKey = 0; /* Zero tells OP_Found to use a composite key */
+ sqlite3VdbeAddOp4(v, OP_MakeRecord, iPk, nPk, iKey,
+ sqlite3IndexAffinityStr(v, pPk), nPk);
+ sqlite3VdbeAddOp2(v, OP_IdxInsert, iEphCur, iKey);
+ }else{
+ /* Get the rowid of the row to be deleted and remember it in the RowSet */
+ nKey = 1; /* OP_Seek always uses a single rowid */
+ sqlite3VdbeAddOp2(v, OP_RowSetAdd, iRowSet, iKey);
+ }
+
+ /* End of the WHERE loop */
sqlite3WhereEnd(pWInfo);
-
- /* Delete every item whose key was written to the list during the
- ** database scan. We have to delete items after the scan is complete
- ** because deleting an item can change the scan order. */
- end = sqlite3VdbeMakeLabel(v);
-
+ if( okOnePass ){
+ /* Bypass the delete logic below if the WHERE loop found zero rows */
+ addrBypass = sqlite3VdbeMakeLabel(v);
+ sqlite3VdbeAddOp2(v, OP_Goto, 0, addrBypass);
+ sqlite3VdbeJumpHere(v, addrDelete);
+ }
+
/* 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. */
+ ** triggers.
+ */
if( !isView ){
- sqlite3OpenTableAndIndices(pParse, pTab, iCur, OP_OpenWrite);
+ sqlite3OpenTableAndIndices(pParse, pTab, OP_OpenWrite, iTabCur, aToOpen,
+ &iDataCur, &iIdxCur);
+ assert( pPk || iDataCur==iTabCur );
+ assert( pPk || iIdxCur==iDataCur+1 );
}
-
- addr = sqlite3VdbeAddOp3(v, OP_RowSetRead, iRowSet, end, iRowid);
-
+
+ /* Set up a loop over the rowids/primary-keys that were found in the
+ ** where-clause loop above.
+ */
+ if( okOnePass ){
+ /* Just one row. Hence the top-of-loop is a no-op */
+ assert( nKey==nPk ); /* OP_Found will use an unpacked key */
+ if( aToOpen[iDataCur-iTabCur] ){
+ assert( pPk!=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, iRowid, pVTab, P4_VTAB);
+ sqlite3VdbeAddOp4(v, OP_VUpdate, 0, 1, iKey, pVTab, P4_VTAB);
sqlite3VdbeChangeP5(v, OE_Abort);
sqlite3MayAbort(pParse);
}else
#endif
{
int count = (pParse->nested==0); /* True to count changes */
- sqlite3GenerateRowDelete(pParse, pTab, iCur, iRowid, count, pTrigger, OE_Default);
+ sqlite3GenerateRowDelete(pParse, pTab, pTrigger, iDataCur, iIdxCur,
+ iKey, nKey, count, OE_Default, okOnePass);
}
-
- /* End of the delete loop */
- sqlite3VdbeAddOp2(v, OP_Goto, 0, addr);
- sqlite3VdbeResolveLabel(v, end);
-
+
+ /* End of the loop over all rowids/primary-keys. */
+ if( okOnePass ){
+ sqlite3VdbeResolveLabel(v, addrBypass);
+ }else if( pPk ){
+ sqlite3VdbeAddOp2(v, OP_Next, iEphCur, addrLoop+1); VdbeCoverage(v);
+ sqlite3VdbeJumpHere(v, addrLoop);
+ }else{
+ sqlite3VdbeAddOp2(v, OP_Goto, 0, addrLoop);
+ sqlite3VdbeJumpHere(v, addrLoop);
+ }
+
/* Close the cursors open on the table and its indexes. */
if( !isView && !IsVirtual(pTab) ){
- for(i=1, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
- sqlite3VdbeAddOp2(v, OP_Close, iCur + i, pIdx->tnum);
+ if( !pPk ) sqlite3VdbeAddOp1(v, OP_Close, iDataCur);
+ for(i=0, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
+ sqlite3VdbeAddOp1(v, OP_Close, iIdxCur + i);
}
- sqlite3VdbeAddOp1(v, OP_Close, iCur);
}
- }
+ } /* End non-truncate path */
/* Update the sqlite_sequence table by storing the content of the
** maximum rowid counter values recorded while inserting into
@@ -445,6 +551,7 @@ delete_from_cleanup:
sqlite3AuthContextPop(&sContext);
sqlite3SrcListDelete(db, pTabList);
sqlite3ExprDelete(db, pWhere);
+ sqlite3DbFree(db, aToOpen);
return;
}
/* Make sure "isView" and other macros defined above are undefined. Otherwise
@@ -459,50 +566,63 @@ delete_from_cleanup:
/*
** This routine generates VDBE code that causes a single row of a
-** single table to be deleted.
+** single table to be deleted. Both the original table entry and
+** all indices are removed.
**
-** The VDBE must be in a particular state when this routine is called.
-** These are the requirements:
+** Preconditions:
**
-** 1. A read/write cursor pointing to pTab, the table containing the row
-** to be deleted, must be opened as cursor number $iCur.
+** 1. iDataCur is an open cursor on the btree that is the canonical data
+** store for the table. (This will be either the table itself,
+** in the case of a rowid table, or the PRIMARY KEY index in the case
+** of a WITHOUT ROWID table.)
**
** 2. Read/write cursors for all indices of pTab must be open as
-** cursor number base+i for the i-th index.
+** cursor number iIdxCur+i for the i-th index.
**
-** 3. The record number of the row to be deleted must be stored in
-** memory cell iRowid.
-**
-** This routine generates code to remove both the table record and all
-** index entries that point to that record.
+** 3. The primary key for the row to be deleted must be stored in a
+** sequence of nPk memory cells starting at iPk. If nPk==0 that means
+** that a search record formed from OP_MakeRecord is contained in the
+** single memory location iPk.
*/
void sqlite3GenerateRowDelete(
Parse *pParse, /* Parsing context */
Table *pTab, /* Table containing the row to be deleted */
- int iCur, /* Cursor number for the table */
- int iRowid, /* Memory cell that contains the rowid to delete */
- int count, /* If non-zero, increment the row change counter */
Trigger *pTrigger, /* List of triggers to (potentially) fire */
- int onconf /* Default ON CONFLICT policy for triggers */
+ int iDataCur, /* Cursor from which column data is extracted */
+ int iIdxCur, /* First index cursor */
+ int iPk, /* First memory cell containing the PRIMARY KEY */
+ i16 nPk, /* Number of PRIMARY KEY memory cells */
+ u8 count, /* If non-zero, increment the row change counter */
+ u8 onconf, /* Default ON CONFLICT policy for triggers */
+ u8 bNoSeek /* iDataCur is already pointing to the row to delete */
){
Vdbe *v = pParse->pVdbe; /* Vdbe */
int iOld = 0; /* First register in OLD.* array */
int iLabel; /* Label resolved to end of generated code */
+ u8 opSeek; /* Seek opcode */
/* Vdbe is guaranteed to have been allocated by this stage. */
assert( v );
+ VdbeModuleComment((v, "BEGIN: GenRowDel(%d,%d,%d,%d)",
+ iDataCur, iIdxCur, iPk, (int)nPk));
/* Seek cursor iCur to the row to delete. If this row no longer exists
** (this can happen if a trigger program has already deleted it), do
** not attempt to delete it or fire any DELETE triggers. */
iLabel = sqlite3VdbeMakeLabel(v);
- sqlite3VdbeAddOp3(v, OP_NotExists, iCur, iLabel, iRowid);
+ opSeek = HasRowid(pTab) ? OP_NotExists : OP_NotFound;
+ if( !bNoSeek ){
+ sqlite3VdbeAddOp4Int(v, opSeek, iDataCur, iLabel, iPk, nPk);
+ VdbeCoverageIf(v, opSeek==OP_NotExists);
+ VdbeCoverageIf(v, opSeek==OP_NotFound);
+ }
/* If there are any triggers to fire, allocate a range of registers to
** use for the old.* references in the triggers. */
if( sqlite3FkRequired(pParse, pTab, 0, 0) || pTrigger ){
u32 mask; /* Mask of OLD.* columns in use */
int iCol; /* Iterator used while populating OLD.* */
+ int addrStart; /* Start of BEFORE trigger programs */
/* TODO: Could use temporary registers here. Also could attempt to
** avoid copying the contents of the rowid register. */
@@ -515,36 +635,44 @@ void sqlite3GenerateRowDelete(
/* Populate the OLD.* pseudo-table register array. These values will be
** used by any BEFORE and AFTER triggers that exist. */
- sqlite3VdbeAddOp2(v, OP_Copy, iRowid, iOld);
+ sqlite3VdbeAddOp2(v, OP_Copy, iPk, iOld);
for(iCol=0; iCol<pTab->nCol; iCol++){
- if( mask==0xffffffff || mask&(1<<iCol) ){
- sqlite3ExprCodeGetColumnOfTable(v, pTab, iCur, iCol, iOld+iCol+1);
+ testcase( mask!=0xffffffff && iCol==31 );
+ testcase( mask!=0xffffffff && iCol==32 );
+ if( mask==0xffffffff || (iCol<=31 && (mask & MASKBIT32(iCol))!=0) ){
+ sqlite3ExprCodeGetColumnOfTable(v, pTab, iDataCur, iCol, iOld+iCol+1);
}
}
/* Invoke BEFORE DELETE trigger programs. */
+ addrStart = sqlite3VdbeCurrentAddr(v);
sqlite3CodeRowTrigger(pParse, pTrigger,
TK_DELETE, 0, TRIGGER_BEFORE, pTab, iOld, onconf, iLabel
);
- /* Seek the cursor to the row to be deleted again. It may be that
- ** the BEFORE triggers coded above have already removed the row
- ** being deleted. Do not attempt to delete the row a second time, and
- ** do not fire AFTER triggers. */
- sqlite3VdbeAddOp3(v, OP_NotExists, iCur, iLabel, iRowid);
+ /* If any BEFORE triggers were coded, then seek the cursor to the
+ ** row to be deleted again. It may be that the BEFORE triggers moved
+ ** the cursor or of already deleted the row that the cursor was
+ ** pointing to.
+ */
+ if( addrStart<sqlite3VdbeCurrentAddr(v) ){
+ sqlite3VdbeAddOp4Int(v, opSeek, iDataCur, iLabel, iPk, nPk);
+ VdbeCoverageIf(v, opSeek==OP_NotExists);
+ VdbeCoverageIf(v, opSeek==OP_NotFound);
+ }
/* Do FK processing. This call checks that any FK constraints that
** refer to this table (i.e. constraints attached to other tables)
** are not violated by deleting this row. */
- sqlite3FkCheck(pParse, pTab, iOld, 0);
+ sqlite3FkCheck(pParse, pTab, iOld, 0, 0, 0);
}
/* Delete the index and table entries. Skip this step if pTab is really
** a view (in which case the only effect of the DELETE statement is to
** fire the INSTEAD OF triggers). */
if( pTab->pSelect==0 ){
- sqlite3GenerateRowIndexDelete(pParse, pTab, iCur, 0);
- sqlite3VdbeAddOp2(v, OP_Delete, iCur, (count?OPFLAG_NCHANGE:0));
+ sqlite3GenerateRowIndexDelete(pParse, pTab, iDataCur, iIdxCur, 0);
+ sqlite3VdbeAddOp2(v, OP_Delete, iDataCur, (count?OPFLAG_NCHANGE:0));
if( count ){
sqlite3VdbeChangeP4(v, -1, pTab->zName, P4_TRANSIENT);
}
@@ -553,7 +681,7 @@ void sqlite3GenerateRowDelete(
/* Do any ON CASCADE, SET NULL or SET DEFAULT operations required to
** handle rows (possibly in other tables) that refer via a foreign key
** to the row just deleted. */
- sqlite3FkActions(pParse, pTab, 0, iOld);
+ sqlite3FkActions(pParse, pTab, 0, iOld, 0, 0);
/* Invoke AFTER DELETE trigger programs. */
sqlite3CodeRowTrigger(pParse, pTrigger,
@@ -564,58 +692,98 @@ void sqlite3GenerateRowDelete(
** trigger programs were invoked. Or if a trigger program throws a
** RAISE(IGNORE) exception. */
sqlite3VdbeResolveLabel(v, iLabel);
+ VdbeModuleComment((v, "END: GenRowDel()"));
}
/*
** This routine generates VDBE code that causes the deletion of all
-** index entries associated with a single row of a single table.
+** index entries associated with a single row of a single table, pTab
**
-** The VDBE must be in a particular state when this routine is called.
-** These are the requirements:
+** Preconditions:
**
-** 1. A read/write cursor pointing to pTab, the table containing the row
-** to be deleted, must be opened as cursor number "iCur".
+** 1. A read/write cursor "iDataCur" must be open on the canonical storage
+** btree for the table pTab. (This will be either the table itself
+** for rowid tables or to the primary key index for WITHOUT ROWID
+** tables.)
**
** 2. Read/write cursors for all indices of pTab must be open as
-** cursor number iCur+i for the i-th index.
+** cursor number iIdxCur+i for the i-th index. (The pTab->pIndex
+** index is the 0-th index.)
**
-** 3. The "iCur" cursor must be pointing to the row that is to be
-** deleted.
+** 3. The "iDataCur" cursor must be already be positioned on the row
+** that is to be deleted.
*/
void sqlite3GenerateRowIndexDelete(
Parse *pParse, /* Parsing and code generating context */
Table *pTab, /* Table containing the row to be deleted */
- int iCur, /* Cursor number for the table */
+ int iDataCur, /* Cursor of table holding data. */
+ int iIdxCur, /* First index cursor */
int *aRegIdx /* Only delete if aRegIdx!=0 && aRegIdx[i]>0 */
){
- int i;
- Index *pIdx;
- int r1;
-
- for(i=1, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
- if( aRegIdx!=0 && aRegIdx[i-1]==0 ) continue;
- r1 = sqlite3GenerateIndexKey(pParse, pIdx, iCur, 0, 0);
- sqlite3VdbeAddOp3(pParse->pVdbe, OP_IdxDelete, iCur+i, r1,pIdx->nColumn+1);
+ int i; /* Index loop counter */
+ int r1 = -1; /* Register holding an index key */
+ int iPartIdxLabel; /* Jump destination for skipping partial index entries */
+ Index *pIdx; /* Current index */
+ Index *pPrior = 0; /* Prior index */
+ Vdbe *v; /* The prepared statement under construction */
+ Index *pPk; /* PRIMARY KEY index, or NULL for rowid tables */
+
+ v = pParse->pVdbe;
+ pPk = HasRowid(pTab) ? 0 : sqlite3PrimaryKeyIndex(pTab);
+ for(i=0, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
+ assert( iIdxCur+i!=iDataCur || pPk==pIdx );
+ if( aRegIdx!=0 && aRegIdx[i]==0 ) continue;
+ if( pIdx==pPk ) continue;
+ VdbeModuleComment((v, "GenRowIdxDel for %s", pIdx->zName));
+ r1 = sqlite3GenerateIndexKey(pParse, pIdx, iDataCur, 0, 1,
+ &iPartIdxLabel, pPrior, r1);
+ sqlite3VdbeAddOp3(v, OP_IdxDelete, iIdxCur+i, r1,
+ pIdx->uniqNotNull ? pIdx->nKeyCol : pIdx->nColumn);
+ sqlite3ResolvePartIdxLabel(pParse, iPartIdxLabel);
+ pPrior = pIdx;
}
}
/*
-** Generate code that will assemble an index key and put it in register
+** Generate code that will assemble an index key and stores it in register
** regOut. The key with be for index pIdx which is an index on pTab.
** iCur is the index of a cursor open on the pTab table and pointing to
-** the entry that needs indexing.
+** the entry that needs indexing. If pTab is a WITHOUT ROWID table, then
+** iCur must be the cursor of the PRIMARY KEY index.
**
** Return a register number which is the first in a block of
** registers that holds the elements of the index key. The
** block of registers has already been deallocated by the time
** this routine returns.
+**
+** If *piPartIdxLabel is not NULL, fill it in with a label and jump
+** to that label if pIdx is a partial index that should be skipped.
+** The label should be resolved using sqlite3ResolvePartIdxLabel().
+** A partial index should be skipped if its WHERE clause evaluates
+** to false or null. If pIdx is not a partial index, *piPartIdxLabel
+** will be set to zero which is an empty label that is ignored by
+** sqlite3ResolvePartIdxLabel().
+**
+** The pPrior and regPrior parameters are used to implement a cache to
+** avoid unnecessary register loads. If pPrior is not NULL, then it is
+** a pointer to a different index for which an index key has just been
+** computed into register regPrior. If the current pIdx index is generating
+** its key into the same sequence of registers and if pPrior and pIdx share
+** a column in common, then the register corresponding to that column already
+** holds the correct value and the loading of that register is skipped.
+** This optimization is helpful when doing a DELETE or an INTEGRITY_CHECK
+** on a table with multiple indices, and especially with the ROWID or
+** PRIMARY KEY columns of the index.
*/
int sqlite3GenerateIndexKey(
- Parse *pParse, /* Parsing context */
- Index *pIdx, /* The index for which to generate a key */
- int iCur, /* Cursor number for the pIdx->pTable table */
- int regOut, /* Write the new index key to this register */
- int doMakeRec /* Run the OP_MakeRecord instruction if true */
+ Parse *pParse, /* Parsing context */
+ Index *pIdx, /* The index for which to generate a key */
+ int iDataCur, /* Cursor number from which to take column data */
+ int regOut, /* Put the new key into this register if not 0 */
+ int prefixOnly, /* Compute only a unique prefix of the key */
+ int *piPartIdxLabel, /* OUT: Jump to this label to skip partial index */
+ Index *pPrior, /* Previously generated index key */
+ int regPrior /* Register holding previous generated key */
){
Vdbe *v = pParse->pVdbe;
int j;
@@ -623,30 +791,47 @@ int sqlite3GenerateIndexKey(
int regBase;
int nCol;
- nCol = pIdx->nColumn;
- regBase = sqlite3GetTempRange(pParse, nCol+1);
- sqlite3VdbeAddOp2(v, OP_Rowid, iCur, regBase+nCol);
- for(j=0; j<nCol; j++){
- int idx = pIdx->aiColumn[j];
- if( idx==pTab->iPKey ){
- sqlite3VdbeAddOp2(v, OP_SCopy, regBase+nCol, regBase+j);
+ if( piPartIdxLabel ){
+ if( pIdx->pPartIdxWhere ){
+ *piPartIdxLabel = sqlite3VdbeMakeLabel(v);
+ pParse->iPartIdxTab = iDataCur;
+ sqlite3ExprCachePush(pParse);
+ sqlite3ExprIfFalse(pParse, pIdx->pPartIdxWhere, *piPartIdxLabel,
+ SQLITE_JUMPIFNULL);
}else{
- sqlite3VdbeAddOp3(v, OP_Column, iCur, idx, regBase+j);
- sqlite3ColumnDefault(v, pTab, idx, -1);
+ *piPartIdxLabel = 0;
}
}
- if( doMakeRec ){
- const char *zAff;
- if( pTab->pSelect
- || OptimizationDisabled(pParse->db, SQLITE_IdxRealAsInt)
- ){
- zAff = 0;
- }else{
- zAff = sqlite3IndexAffinityStr(v, pIdx);
- }
- sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase, nCol+1, regOut);
- sqlite3VdbeChangeP4(v, -1, zAff, P4_TRANSIENT);
+ nCol = (prefixOnly && pIdx->uniqNotNull) ? pIdx->nKeyCol : pIdx->nColumn;
+ regBase = sqlite3GetTempRange(pParse, nCol);
+ if( pPrior && (regBase!=regPrior || pPrior->pPartIdxWhere) ) pPrior = 0;
+ for(j=0; j<nCol; j++){
+ if( pPrior && pPrior->aiColumn[j]==pIdx->aiColumn[j] ) continue;
+ sqlite3ExprCodeGetColumnOfTable(v, pTab, iDataCur, pIdx->aiColumn[j],
+ regBase+j);
+ /* If the column affinity is REAL but the number is an integer, then it
+ ** might be stored in the table as an integer (using a compact
+ ** representation) then converted to REAL by an OP_RealAffinity opcode.
+ ** But we are getting ready to store this value back into an index, where
+ ** it should be converted by to INTEGER again. So omit the OP_RealAffinity
+ ** opcode if it is present */
+ sqlite3VdbeDeletePriorOpcode(v, OP_RealAffinity);
}
- sqlite3ReleaseTempRange(pParse, regBase, nCol+1);
+ if( regOut ){
+ sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase, nCol, regOut);
+ }
+ sqlite3ReleaseTempRange(pParse, regBase, nCol);
return regBase;
}
+
+/*
+** If a prior call to sqlite3GenerateIndexKey() generated a jump-over label
+** because it was a partial index, then this routine should be called to
+** resolve that label.
+*/
+void sqlite3ResolvePartIdxLabel(Parse *pParse, int iLabel){
+ if( iLabel ){
+ sqlite3VdbeResolveLabel(pParse->pVdbe, iLabel);
+ sqlite3ExprCachePop(pParse);
+ }
+}