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Diffstat (limited to '')
| -rw-r--r-- | src/upsert.c | 316 |
1 files changed, 316 insertions, 0 deletions
diff --git a/src/upsert.c b/src/upsert.c new file mode 100644 index 0000000..8599402 --- /dev/null +++ b/src/upsert.c @@ -0,0 +1,316 @@ +/* +** 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 +*/ +static void SQLITE_NOINLINE upsertDelete(sqlite3 *db, Upsert *p){ + do{ + Upsert *pNext = p->pNextUpsert; + sqlite3ExprListDelete(db, p->pUpsertTarget); + sqlite3ExprDelete(db, p->pUpsertTargetWhere); + sqlite3ExprListDelete(db, p->pUpsertSet); + sqlite3ExprDelete(db, p->pUpsertWhere); + sqlite3DbFree(db, p->pToFree); + sqlite3DbFree(db, p); + p = pNext; + }while( p ); +} +void sqlite3UpsertDelete(sqlite3 *db, Upsert *p){ + if( p ) upsertDelete(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), + sqlite3UpsertDup(db, p->pNextUpsert) + ); +} + +/* +** 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 *pNext /* Next ON CONFLICT clause in the list */ +){ + Upsert *pNew; + pNew = sqlite3DbMallocZero(db, sizeof(Upsert)); + if( pNew==0 ){ + sqlite3ExprListDelete(db, pTarget); + sqlite3ExprDelete(db, pTargetWhere); + sqlite3ExprListDelete(db, pSet); + sqlite3ExprDelete(db, pWhere); + sqlite3UpsertDelete(db, pNext); + return 0; + }else{ + pNew->pUpsertTarget = pTarget; + pNew->pUpsertTargetWhere = pTargetWhere; + pNew->pUpsertSet = pSet; + pNew->pUpsertWhere = pWhere; + pNew->isDoUpdate = pSet!=0; + pNew->pNextUpsert = pNext; + } + 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 */ + int nClause = 0; /* Counter of ON CONFLICT clauses */ + + 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; + for(; pUpsert && pUpsert->pUpsertTarget; + pUpsert=pUpsert->pNextUpsert, nClause++){ + 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 ); + continue; + } + + /* 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 ); + assert( pIdx->bHasExpr ); + 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; + break; + } + if( pUpsert->pUpsertIdx==0 ){ + char zWhich[16]; + if( nClause==0 && pUpsert->pNextUpsert==0 ){ + zWhich[0] = 0; + }else{ + sqlite3_snprintf(sizeof(zWhich),zWhich,"%r ", nClause+1); + } + sqlite3ErrorMsg(pParse, "%sON CONFLICT clause does not match any " + "PRIMARY KEY or UNIQUE constraint", zWhich); + return SQLITE_ERROR; + } + } + return SQLITE_OK; +} + +/* +** Return true if pUpsert is the last ON CONFLICT clause with a +** conflict target, or if pUpsert is followed by another ON CONFLICT +** clause that targets the INTEGER PRIMARY KEY. +*/ +int sqlite3UpsertNextIsIPK(Upsert *pUpsert){ + Upsert *pNext; + if( NEVER(pUpsert==0) ) return 0; + pNext = pUpsert->pNextUpsert; + if( pNext==0 ) return 1; + if( pNext->pUpsertTarget==0 ) return 1; + if( pNext->pUpsertIdx==0 ) return 1; + return 0; +} + +/* +** Given the list of ON CONFLICT clauses described by pUpsert, and +** a particular index pIdx, return a pointer to the particular ON CONFLICT +** clause that applies to the index. Or, if the index is not subject to +** any ON CONFLICT clause, return NULL. +*/ +Upsert *sqlite3UpsertOfIndex(Upsert *pUpsert, Index *pIdx){ + while( + pUpsert + && pUpsert->pUpsertTarget!=0 + && pUpsert->pUpsertIdx!=pIdx + ){ + pUpsert = pUpsert->pNextUpsert; + } + return pUpsert; +} + +/* +** 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; + Upsert *pTop = pUpsert; + + assert( v!=0 ); + assert( pUpsert!=0 ); + iDataCur = pUpsert->iDataCur; + pUpsert = sqlite3UpsertOfIndex(pTop, pIdx); + VdbeNoopComment((v, "Begin DO UPDATE of UPSERT")); + 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 = sqlite3TableColumnToIndex(pIdx, pPk->aiColumn[i]); + sqlite3VdbeAddOp3(v, OP_Column, iCur, k, iPk+i); + VdbeComment((v, "%s.%s", pIdx->zName, + pTab->aCol[pPk->aiColumn[i]].zCnName)); + } + 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); + sqlite3MayAbort(pParse); + sqlite3VdbeJumpHere(v, i); + } + } + /* pUpsert does not own pTop->pUpsertSrc - the outer INSERT statement does. + ** So we have to make a copy before passing it down into sqlite3Update() */ + pSrc = sqlite3SrcListDup(db, pTop->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, pTop->regData+i); + } + } + sqlite3Update(pParse, pSrc, sqlite3ExprListDup(db,pUpsert->pUpsertSet,0), + sqlite3ExprDup(db,pUpsert->pUpsertWhere,0), OE_Abort, 0, 0, pUpsert); + VdbeNoopComment((v, "End DO UPDATE of UPSERT")); +} + +#endif /* SQLITE_OMIT_UPSERT */ |