/*
** 2018-04-12
**
** The author disclaims copyright to this source code. In place of
** a legal notice, here is a blessing:
**
** May you do good and not evil.
** May you find forgiveness for yourself and forgive others.
** May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains code to implement various aspects of UPSERT
** processing and handling of the Upsert object.
*/
#include "sqliteInt.h"
#ifndef SQLITE_OMIT_UPSERT
/*
** Free a list of Upsert objects
*/
void sqlite3UpsertDelete(sqlite3 *db, Upsert *p){
if( p ){
sqlite3ExprListDelete(db, p->pUpsertTarget);
sqlite3ExprDelete(db, p->pUpsertTargetWhere);
sqlite3ExprListDelete(db, p->pUpsertSet);
sqlite3ExprDelete(db, p->pUpsertWhere);
sqlite3DbFree(db, p);
}
}
/*
** Duplicate an Upsert object.
*/
Upsert *sqlite3UpsertDup(sqlite3 *db, Upsert *p){
if( p==0 ) return 0;
return sqlite3UpsertNew(db,
sqlite3ExprListDup(db, p->pUpsertTarget, 0),
sqlite3ExprDup(db, p->pUpsertTargetWhere, 0),
sqlite3ExprListDup(db, p->pUpsertSet, 0),
sqlite3ExprDup(db, p->pUpsertWhere, 0)
);
}
/*
** Create a new Upsert object.
*/
Upsert *sqlite3UpsertNew(
sqlite3 *db, /* Determines which memory allocator to use */
ExprList *pTarget, /* Target argument to ON CONFLICT, or NULL */
Expr *pTargetWhere, /* Optional WHERE clause on the target */
ExprList *pSet, /* UPDATE columns, or NULL for a DO NOTHING */
Expr *pWhere /* WHERE clause for the ON CONFLICT UPDATE */
){
Upsert *pNew;
pNew = sqlite3DbMallocRaw(db, sizeof(Upsert));
if( pNew==0 ){
sqlite3ExprListDelete(db, pTarget);
sqlite3ExprDelete(db, pTargetWhere);
sqlite3ExprListDelete(db, pSet);
sqlite3ExprDelete(db, pWhere);
return 0;
}else{
pNew->pUpsertTarget = pTarget;
pNew->pUpsertTargetWhere = pTargetWhere;
pNew->pUpsertSet = pSet;
pNew->pUpsertWhere = pWhere;
pNew->pUpsertIdx = 0;
}
return pNew;
}
/*
** Analyze the ON CONFLICT clause described by pUpsert. Resolve all
** symbols in the conflict-target.
**
** Return SQLITE_OK if everything works, or an error code is something
** is wrong.
*/
int sqlite3UpsertAnalyzeTarget(
Parse *pParse, /* The parsing context */
SrcList *pTabList, /* Table into which we are inserting */
Upsert *pUpsert /* The ON CONFLICT clauses */
){
Table *pTab; /* That table into which we are inserting */
int rc; /* Result code */
int iCursor; /* Cursor used by pTab */
Index *pIdx; /* One of the indexes of pTab */
ExprList *pTarget; /* The conflict-target clause */
Expr *pTerm; /* One term of the conflict-target clause */
NameContext sNC; /* Context for resolving symbolic names */
Expr sCol[2]; /* Index column converted into an Expr */
assert( pTabList->nSrc==1 );
assert( pTabList->a[0].pTab!=0 );
assert( pUpsert!=0 );
assert( pUpsert->pUpsertTarget!=0 );
/* Resolve all symbolic names in the conflict-target clause, which
** includes both the list of columns and the optional partial-index
** WHERE clause.
*/
memset(&sNC, 0, sizeof(sNC));
sNC.pParse = pParse;
sNC.pSrcList = pTabList;
rc = sqlite3ResolveExprListNames(&sNC, pUpsert->pUpsertTarget);
if( rc ) return rc;
rc = sqlite3ResolveExprNames(&sNC, pUpsert->pUpsertTargetWhere);
if( rc ) return rc;
/* Check to see if the conflict target matches the rowid. */
pTab = pTabList->a[0].pTab;
pTarget = pUpsert->pUpsertTarget;
iCursor = pTabList->a[0].iCursor;
if( HasRowid(pTab)
&& pTarget->nExpr==1
&& (pTerm = pTarget->a[0].pExpr)->op==TK_COLUMN
&& pTerm->iColumn==XN_ROWID
){
/* The conflict-target is the rowid of the primary table */
assert( pUpsert->pUpsertIdx==0 );
return SQLITE_OK;
}
/* Initialize sCol[0..1] to be an expression parse tree for a
** single column of an index. The sCol[0] node will be the TK_COLLATE
** operator and sCol[1] will be the TK_COLUMN operator. Code below
** will populate the specific collation and column number values
** prior to comparing against the conflict-target expression.
*/
memset(sCol, 0, sizeof(sCol));
sCol[0].op = TK_COLLATE;
sCol[0].pLeft = &sCol[1];
sCol[1].op = TK_COLUMN;
sCol[1].iTable = pTabList->a[0].iCursor;
/* Check for matches against other indexes */
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
int ii, jj, nn;
if( !IsUniqueIndex(pIdx) ) continue;
if( pTarget->nExpr!=pIdx->nKeyCol ) continue;
if( pIdx->pPartIdxWhere ){
if( pUpsert->pUpsertTargetWhere==0 ) continue;
if( sqlite3ExprCompare(pParse, pUpsert->pUpsertTargetWhere,
pIdx->pPartIdxWhere, iCursor)!=0 ){
continue;
}
}
nn = pIdx->nKeyCol;
for(ii=0; ii<nn; ii++){
Expr *pExpr;
sCol[0].u.zToken = (char*)pIdx->azColl[ii];
if( pIdx->aiColumn[ii]==XN_EXPR ){
assert( pIdx->aColExpr!=0 );
assert( pIdx->aColExpr->nExpr>ii );
pExpr = pIdx->aColExpr->a[ii].pExpr;
if( pExpr->op!=TK_COLLATE ){
sCol[0].pLeft = pExpr;
pExpr = &sCol[0];
}
}else{
sCol[0].pLeft = &sCol[1];
sCol[1].iColumn = pIdx->aiColumn[ii];
pExpr = &sCol[0];
}
for(jj=0; jj<nn; jj++){
if( sqlite3ExprCompare(pParse, pTarget->a[jj].pExpr, pExpr,iCursor)<2 ){
break; /* Column ii of the index matches column jj of target */
}
}
if( jj>=nn ){
/* The target contains no match for column jj of the index */
break;
}
}
if( ii<nn ){
/* Column ii of the index did not match any term of the conflict target.
** Continue the search with the next index. */
continue;
}
pUpsert->pUpsertIdx = pIdx;
return SQLITE_OK;
}
sqlite3ErrorMsg(pParse, "ON CONFLICT clause does not match any "
"PRIMARY KEY or UNIQUE constraint");
return SQLITE_ERROR;
}
/*
** Generate bytecode that does an UPDATE as part of an upsert.
**
** If pIdx is NULL, then the UNIQUE constraint that failed was the IPK.
** In this case parameter iCur is a cursor open on the table b-tree that
** currently points to the conflicting table row. Otherwise, if pIdx
** is not NULL, then pIdx is the constraint that failed and iCur is a
** cursor points to the conflicting row.
*/
void sqlite3UpsertDoUpdate(
Parse *pParse, /* The parsing and code-generating context */
Upsert *pUpsert, /* The ON CONFLICT clause for the upsert */
Table *pTab, /* The table being updated */
Index *pIdx, /* The UNIQUE constraint that failed */
int iCur /* Cursor for pIdx (or pTab if pIdx==NULL) */
){
Vdbe *v = pParse->pVdbe;
sqlite3 *db = pParse->db;
SrcList *pSrc; /* FROM clause for the UPDATE */
int iDataCur;
int i;
assert( v!=0 );
assert( pUpsert!=0 );
VdbeNoopComment((v, "Begin DO UPDATE of UPSERT"));
iDataCur = pUpsert->iDataCur;
if( pIdx && iCur!=iDataCur ){
if( HasRowid(pTab) ){
int regRowid = sqlite3GetTempReg(pParse);
sqlite3VdbeAddOp2(v, OP_IdxRowid, iCur, regRowid);
sqlite3VdbeAddOp3(v, OP_SeekRowid, iDataCur, 0, regRowid);
VdbeCoverage(v);
sqlite3ReleaseTempReg(pParse, regRowid);
}else{
Index *pPk = sqlite3PrimaryKeyIndex(pTab);
int nPk = pPk->nKeyCol;
int iPk = pParse->nMem+1;
pParse->nMem += nPk;
for(i=0; i<nPk; i++){
int k;
assert( pPk->aiColumn[i]>=0 );
k = sqlite3ColumnOfIndex(pIdx, pPk->aiColumn[i]);
sqlite3VdbeAddOp3(v, OP_Column, iCur, k, iPk+i);
VdbeComment((v, "%s.%s", pIdx->zName,
pTab->aCol[pPk->aiColumn[i]].zName));
}
sqlite3VdbeVerifyAbortable(v, OE_Abort);
i = sqlite3VdbeAddOp4Int(v, OP_Found, iDataCur, 0, iPk, nPk);
VdbeCoverage(v);
sqlite3VdbeAddOp4(v, OP_Halt, SQLITE_CORRUPT, OE_Abort, 0,
"corrupt database", P4_STATIC);
sqlite3VdbeJumpHere(v, i);
}
}
/* pUpsert does not own pUpsertSrc - the outer INSERT statement does. So
** we have to make a copy before passing it down into sqlite3Update() */
pSrc = sqlite3SrcListDup(db, pUpsert->pUpsertSrc, 0);
/* excluded.* columns of type REAL need to be converted to a hard real */
for(i=0; i<pTab->nCol; i++){
if( pTab->aCol[i].affinity==SQLITE_AFF_REAL ){
sqlite3VdbeAddOp1(v, OP_RealAffinity, pUpsert->regData+i);
}
}
sqlite3Update(pParse, pSrc, pUpsert->pUpsertSet,
pUpsert->pUpsertWhere, OE_Abort, 0, 0, pUpsert);
pUpsert->pUpsertSet = 0; /* Will have been deleted by sqlite3Update() */
pUpsert->pUpsertWhere = 0; /* Will have been deleted by sqlite3Update() */
VdbeNoopComment((v, "End DO UPDATE of UPSERT"));
}
#endif /* SQLITE_OMIT_UPSERT */