From b83524795427e9ad8131fe9827e397f973b37932 Mon Sep 17 00:00:00 2001 From: drh <> Date: Fri, 29 Jan 2021 19:32:17 +0000 Subject: [PATCH] Working prototype. FossilOrigin-Name: b7ef4dc21f187ff4ff679e823782535188c3814aa6ce720b3a01c6d3ba4ef9f5 --- manifest | 26 +++++++++++++------------- manifest.uuid | 2 +- src/build.c | 46 ++++++++++++++++++++++++++++++++++++++++++++-- src/fkey.c | 3 ++- src/parse.y | 4 ++-- src/resolve.c | 11 +++++++---- src/sqliteInt.h | 17 ++++++++++++++++- src/trigger.c | 20 +++++++++++++++++--- src/vdbe.h | 1 + src/vdbeaux.c | 14 ++++++++++++++ 10 files changed, 117 insertions(+), 27 deletions(-) diff --git a/manifest b/manifest index d18146bacc..4720b86680 100644 --- a/manifest +++ b/manifest @@ -1,5 +1,5 @@ -C Incorporate\sthe\ssqlite3TriggerList()\soptimization\sfrom\strunk.\s\sAnd\smove\nthe\spReturning\sfield\sto\sthe\suninitialized\sarea\sin\sthe\sParse\sobject,\sto\nsave\smemset()\stime. -D 2021-01-29T14:22:56.875 +C Working\sprototype. +D 2021-01-29T19:32:17.139 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724 @@ -485,7 +485,7 @@ F src/btmutex.c 8acc2f464ee76324bf13310df5692a262b801808984c1b79defb2503bbafadb6 F src/btree.c 47d9fe97d5c0d74506154e3597f8a23b81a00080751dc4d11fec91ee22796f4c F src/btree.h 285f8377aa1353185a32bf455faafa9ff9a0d40d074d60509534d14990c7829e F src/btreeInt.h 7614cae30f95b6aed0c7cac7718276a55cfe2c77058cbfd8bef5b75329757331 -F src/build.c ba8af18891c07501a185ecd02a2bc13a593de9bfd59dbffa5d126780c0c9fb8e +F src/build.c 2aded84176695b0f885eec582f3afbe667737998a14fb39b3eb6623626a8f2b5 F src/callback.c d0b853dd413255d2e337b34545e54d888ea02f20da5ad0e63585b389624c4a6c F src/complete.c a3634ab1e687055cd002e11b8f43eb75c17da23e F src/ctime.c 2a322b9a3d75771fb4d99e0702851f4f68dda982507a0f798eefb0712969a410 @@ -495,7 +495,7 @@ F src/dbstat.c 3aa79fc3aed7ce906e4ea6c10e85d657299e304f6049861fe300053ac57de36c F src/delete.c 927cf8f900583e79aca8f1a321979e0a8f053babd9a690b44b38f79de2cc09fe F src/expr.c 47c85263e6d179424e6b09e2c79db5704ab5b8cbc2fae2ee3285faa2566f2e74 F src/fault.c 460f3e55994363812d9d60844b2a6de88826e007 -F src/fkey.c 83372403298e6a7dd989a47aaacdbaa5b4307b5199dbd56e07d4896066b3de72 +F src/fkey.c df06098e66c95bb5169e2e79eb59583efe00794e6345e196e776dd6f4b1ea33b F src/func.c 796a7a4a0ff5eee82a04ee3c8265c5ebf9c6a9f5625621c5f97ed94f6224d7d9 F src/global.c ed55af196a9b66e198aaeda3f5454c3aa7d7d050c6c938181fd044b70d180a81 F src/hash.c 8d7dda241d0ebdafb6ffdeda3149a412d7df75102cecfc1021c98d6219823b19 @@ -530,7 +530,7 @@ F src/os_win.c 77d39873836f1831a9b0b91894fec45ab0e9ca8e067dc8c549e1d1eca1566fe9 F src/os_win.h 7b073010f1451abe501be30d12f6bc599824944a F src/pager.c c49952ac5e9cc536778eff528091d79d38b3e45cbeeed4695dc05e207dc6547d F src/pager.h 4bf9b3213a4b2bebbced5eaa8b219cf25d4a82f385d093cd64b7e93e5285f66f -F src/parse.y 6b462c25bae7e0c53f2935f9157f82abeba07754905ef8835c978742c5473ff3 +F src/parse.y 67ba503780de64b967ae195b7e14c33531329228e1bc0b83d63324beb733680b F src/pcache.c 385ff064bca69789d199a98e2169445dc16e4291fa807babd61d4890c3b34177 F src/pcache.h 4f87acd914cef5016fae3030343540d75f5b85a1877eed1a2a19b9f284248586 F src/pcache1.c 6596e10baf3d8f84cc1585d226cf1ab26564a5f5caf85a15757a281ff977d51a @@ -539,14 +539,14 @@ F src/pragma.h 8dc78ab7e9ec6ce3ded8332810a2066f1ef6267e2e03cd7356ee00276125c6cf F src/prepare.c f288cbc35f79eb32e162de7e80a63ebe00d80e639dcfac071bee11570cbdb16f F src/printf.c 30e92b638fac71dcd85cdea1d12ecfae354c9adee2c71e8e1ae4727cde7c91ed F src/random.c 80f5d666f23feb3e6665a6ce04c7197212a88384 -F src/resolve.c 1948a92ca9eab776632816b97e57c61d933474a78aad4f4ef835c916a83dbb1c +F src/resolve.c b714e6f9f3cdfb6ba287bb5ef76888ec8cd9e15c98a608c82bc3300b99a245d7 F src/rowset.c ba9515a922af32abe1f7d39406b9d35730ed65efab9443dc5702693b60854c92 F src/select.c 738cb746189f721f59972993c13085fa2975c4cbfd04ba26445f3b42c81237dc F src/shell.c.in 9ebc74e4f05cfbd0f4a36060fdaeff1da4e9af4458358722bc08c5a1ab9a0879 F src/sqlite.h.in 0af968a1fa3c717261e1df0ed105fa7bddb4d82de7e0adb3eab49e6aa81b4de7 F src/sqlite3.rc 5121c9e10c3964d5755191c80dd1180c122fc3a8 F src/sqlite3ext.h 61b38c073d5e1e96a3d45271b257aef27d0d13da2bea5347692ae579475cd95e -F src/sqliteInt.h aebfa715feaf134b5d0cf6a2dccb4a4d0172d7915658c69abd5b3a0cb3b794d3 +F src/sqliteInt.h e3ad4cc28df195a9676d9f108d2cd1d41da6b505950797dc069094d90fd9f197 F src/sqliteLimit.h d7323ffea5208c6af2734574bae933ca8ed2ab728083caa117c9738581a31657 F src/status.c 4b8bc2a6905163a38b739854a35b826c737333fab5b1f8e03fa7eb9a4799c4c1 F src/table.c 0f141b58a16de7e2fbe81c308379e7279f4c6b50eb08efeec5892794a0ba30d1 @@ -607,17 +607,17 @@ F src/test_wsd.c 41cadfd9d97fe8e3e4e44f61a4a8ccd6f7ca8fe9 F src/threads.c 4ae07fa022a3dc7c5beb373cf744a85d3c5c6c3c F src/tokenize.c c64c49d7c2ec4490c2fef1f24350167ba16b03b0c6cee58ad1a1d70a4325d4e9 F src/treeview.c 4b92992176fb2caefbe06ba5bd06e0e0ebcde3d5564758da672631f17aa51cda -F src/trigger.c 731ea5ed6b308574b7dc2a5d2a9187ef5510a3692cc1ea06a34608a084b8f376 +F src/trigger.c 39ac8d708d6c929817c230fba0cf1ef5bd7ac52ce883df8ab49bcdc28817a787 F src/update.c 9f126204a6acb96bbe47391ae48e0fc579105d8e76a6d9c4fab3271367476580 F src/upsert.c df8f1727d62b5987c4fd302cd4d7c0c84ae57cd65683c5a34a740dfe24039235 F src/utf.c ee39565f0843775cc2c81135751ddd93eceb91a673ea2c57f61c76f288b041a0 F src/util.c 41c7a72da1df47864faa378a1c720b38adb288c6838cb6be5594511b6287a048 F src/vacuum.c 492422c1463c076473bae1858799c7a0a5fe87a133d1223239447c422cd26286 F src/vdbe.c 102d21260bddbb43c845603c3a2d6b4f3762e72f836ccda12991f291485d2539 -F src/vdbe.h 83603854bfa5851af601fc0947671eb260f4363e62e960e8a994fb9bbcd2aaa1 +F src/vdbe.h a71bf43572d3de57923d1928ac01ae8d355cd67e94462ba4f7462265cedbef9a F src/vdbeInt.h 3ca5e9fd6e095a8b6cf6bc3587a46fc93499503b2fe48951e1034ba9e2ce2f6e F src/vdbeapi.c c5e7cb2ab89a24d7f723e87b508f21bfb1359a04db5277d8a99fd1e015c12eb9 -F src/vdbeaux.c e91d74e24babcf61969279b193e228cf4f8bc724a9cc59ed287db064326876f8 +F src/vdbeaux.c 7ae7b2d7d97250d7100065eca7f04324f331b16b8165775f1724af10c7240d11 F src/vdbeblob.c 253ed82894924c362a7fa3079551d3554cd1cdace39aa833da77d3bc67e7c1b1 F src/vdbemem.c 947f2a65910edb4014dc981d33e414a68c51f169f9df8c4c493a0ba840b6eb1f F src/vdbesort.c f5b5e473a7cee44e47a94817b042fd7172cf3aa2c0a7928a8339d612bcfdec5a @@ -1898,7 +1898,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0 -P 5fbcb208d24d45169fc53ad8738dd3545d9bbd26b7434e31afc7f6419cd4e958 0defaf730bdc82212a5d3feeb2e16f16423b1691b0aaa7da1787eb82ea39ae9e -R c5cf37660ce1737a23c63b9fdc43eb3e +P 29fbaf0e3eabda08500f350bc32e9f339e5732a65bfa62822eefb692a2ff0243 +R 0f4eeb3bbbe288c435a7916147e604d5 U drh -Z c6d2a25c829d2b926a3cb0974507f1ba +Z cf32b347d108b527d7c22e05c5929805 diff --git a/manifest.uuid b/manifest.uuid index 64051cb566..9c5f6afd5b 100644 --- a/manifest.uuid +++ b/manifest.uuid @@ -1 +1 @@ -29fbaf0e3eabda08500f350bc32e9f339e5732a65bfa62822eefb692a2ff0243 \ No newline at end of file +b7ef4dc21f187ff4ff679e823782535188c3814aa6ce720b3a01c6d3ba4ef9f5 \ No newline at end of file diff --git a/src/build.c b/src/build.c index 5b4bbe499b..99ecad4d63 100644 --- a/src/build.c +++ b/src/build.c @@ -1243,13 +1243,55 @@ void sqlite3ColumnPropertiesFromName(Table *pTab, Column *pCol){ } #endif +/* +** Name of the magic TEMP trigger used to implement RETURNING +*/ +#define RETURNING_TRIGGER "sqlite_returning" + +/* +** Delete the data structures associated with the RETURNING clause. +*/ +static void sqlite3DeleteReturning(sqlite3 *db, Returning *pRet){ + Hash *pHash; + pHash = &(db->aDb[1].pSchema->trigHash); + assert( sqlite3HashFind(pHash, RETURNING_TRIGGER)==&pRet->retTrig ); + sqlite3HashInsert(pHash, RETURNING_TRIGGER, 0); + sqlite3ExprListDelete(db, pRet->pReturnEL); + sqlite3DbFree(db, pRet); +} + /* ** Add the RETURNING clause to the parser currently underway. */ void sqlite3AddReturning(Parse *pParse, ExprList *pList){ + Returning *pRet; + Hash *pHash; + sqlite3 *db = pParse->db; + pRet = sqlite3DbMallocZero(db, sizeof(*pRet)); + if( pRet==0 ){ + sqlite3ExprListDelete(db, pList); + return; + } + pRet->pParse = pParse; + pRet->pReturnEL = pList; sqlite3ParserAddCleanup(pParse, - (void(*)(sqlite3*,void*))sqlite3ExprListDelete, pList); - pParse->pReturning = pList; + (void(*)(sqlite3*,void*))sqlite3DeleteReturning, pRet); + pRet->retTrig.zName = "sqlite_returning"; + pRet->retTrig.op = TK_RETURNING; + pRet->retTrig.tr_tm = TRIGGER_AFTER; + pRet->retTrig.bReturning = 1; + pRet->retTrig.pSchema = db->aDb[1].pSchema; + pRet->retTrig.step_list = &pRet->retTStep; + pRet->retTStep.op = TK_SELECT; + pRet->retTStep.eTrigDest = SRT_Output; + pRet->retTStep.pTrig = &pRet->retTrig; + pRet->retTStep.pSelect = &pRet->retSel; + pRet->retSel.op = TK_ALL; + pRet->retSel.pEList = pList; + pRet->retSel.pSrc = (SrcList*)&pRet->retSrcList; + pHash = &(db->aDb[1].pSchema->trigHash); + assert( sqlite3HashFind(pHash, RETURNING_TRIGGER)==0 ); + sqlite3HashInsert(pHash, "sqlite_returning", &pRet->retTrig); } /* diff --git a/src/fkey.c b/src/fkey.c index 959e994d17..4cb92e2915 100644 --- a/src/fkey.c +++ b/src/fkey.c @@ -1352,7 +1352,8 @@ static Trigger *fkActionTrigger( switch( action ){ case OE_Restrict: - pStep->op = TK_SELECT; + pStep->op = TK_SELECT; + pStep->eTrigDest = SRT_Discard; break; case OE_Cascade: if( !pChanges ){ diff --git a/src/parse.y b/src/parse.y index 4c79d4a87a..591cde3b9d 100644 --- a/src/parse.y +++ b/src/parse.y @@ -905,7 +905,7 @@ where_opt_ret(A) ::= WHERE expr(X) RETURNING selcollist(Y). // %if SQLITE_ENABLE_UPDATE_DELETE_LIMIT || SQLITE_UDL_CAPABLE_PARSER cmd ::= with UPDATE orconf(R) xfullname(X) indexed_opt(I) SET setlist(Y) from(F) - where_opt(W) orderby_opt(O) limit_opt(L). { + where_opt_ret(W) orderby_opt(O) limit_opt(L). { sqlite3SrcListIndexedBy(pParse, X, &I); X = sqlite3SrcListAppendList(pParse, X, F); sqlite3ExprListCheckLength(pParse,Y,"set list"); @@ -920,7 +920,7 @@ cmd ::= with UPDATE orconf(R) xfullname(X) indexed_opt(I) SET setlist(Y) from(F) } %else cmd ::= with UPDATE orconf(R) xfullname(X) indexed_opt(I) SET setlist(Y) from(F) - where_opt(W). { + where_opt_ret(W). { sqlite3SrcListIndexedBy(pParse, X, &I); sqlite3ExprListCheckLength(pParse,Y,"set list"); X = sqlite3SrcListAppendList(pParse, X, F); diff --git a/src/resolve.c b/src/resolve.c index b55bdc4187..fa46954da8 100644 --- a/src/resolve.c +++ b/src/resolve.c @@ -371,23 +371,26 @@ static int lookupName( ** it is a new.* or old.* trigger argument reference. Or ** maybe it is an excluded.* from an upsert. */ - if( zDb==0 && zTab!=0 && cntTab==0 ){ + if( zDb==0 && cntTab==0 ){ pTab = 0; #ifndef SQLITE_OMIT_TRIGGER if( pParse->pTriggerTab!=0 ){ int op = pParse->eTriggerOp; assert( op==TK_DELETE || op==TK_UPDATE || op==TK_INSERT ); - if( op!=TK_DELETE && sqlite3StrICmp("new",zTab) == 0 ){ + if( op!=TK_DELETE && zTab && sqlite3StrICmp("new",zTab) == 0 ){ pExpr->iTable = 1; pTab = pParse->pTriggerTab; - }else if( op!=TK_INSERT && sqlite3StrICmp("old",zTab)==0 ){ + }else if( op!=TK_INSERT && zTab && sqlite3StrICmp("old",zTab)==0 ){ pExpr->iTable = 0; pTab = pParse->pTriggerTab; + }else if( pParse->bReturning ){ + pExpr->iTable = op!=TK_DELETE; + pTab = pParse->pTriggerTab; } } #endif /* SQLITE_OMIT_TRIGGER */ #ifndef SQLITE_OMIT_UPSERT - if( (pNC->ncFlags & NC_UUpsert)!=0 ){ + if( (pNC->ncFlags & NC_UUpsert)!=0 && zTab ){ Upsert *pUpsert = pNC->uNC.pUpsert; if( pUpsert && sqlite3StrICmp("excluded",zTab)==0 ){ pTab = pUpsert->pUpsertSrc->a[0].pTab; diff --git a/src/sqliteInt.h b/src/sqliteInt.h index c66b44290c..231ead5062 100644 --- a/src/sqliteInt.h +++ b/src/sqliteInt.h @@ -1159,6 +1159,7 @@ typedef struct ParseCleanup ParseCleanup; typedef struct PreUpdate PreUpdate; typedef struct PrintfArguments PrintfArguments; typedef struct RenameToken RenameToken; +typedef struct Returning Returning; typedef struct RowSet RowSet; typedef struct Savepoint Savepoint; typedef struct Select Select; @@ -3429,6 +3430,7 @@ struct Parse { u32 oldmask; /* Mask of old.* columns referenced */ u32 newmask; /* Mask of new.* columns referenced */ u8 eTriggerOp; /* TK_UPDATE, TK_INSERT or TK_DELETE */ + u8 bReturning; /* Coding a RETURNING trigger */ u8 eOrconf; /* Default ON CONFLICT policy for trigger steps */ u8 disableTriggers; /* True to disable triggers */ @@ -3441,7 +3443,6 @@ struct Parse { int aTempReg[8]; /* Holding area for temporary registers */ Token sNameToken; /* Token with unqualified schema object name */ - ExprList *pReturning; /* The RETURNING clause, if any */ /************************************************************************ ** Above is constant between recursions. Below is reset before and after @@ -3579,6 +3580,7 @@ struct Trigger { char *table; /* The table or view to which the trigger applies */ u8 op; /* One of TK_DELETE, TK_UPDATE, TK_INSERT */ u8 tr_tm; /* One of TRIGGER_BEFORE, TRIGGER_AFTER */ + u8 bReturning; /* This trigger implements a RETURNING clause */ Expr *pWhen; /* The WHEN clause of the expression (may be NULL) */ IdList *pColumns; /* If this is an UPDATE OF trigger, the is stored here */ @@ -3639,6 +3641,7 @@ struct Trigger { struct TriggerStep { u8 op; /* One of TK_DELETE, TK_UPDATE, TK_INSERT, TK_SELECT */ u8 orconf; /* OE_Rollback etc. */ + u8 eTrigDest; /* SRT_ destination value for SELECT */ Trigger *pTrig; /* The trigger that this step is a part of */ Select *pSelect; /* SELECT statement or RHS of INSERT INTO SELECT ... */ char *zTarget; /* Target table for DELETE, UPDATE, INSERT */ @@ -3652,6 +3655,18 @@ struct TriggerStep { TriggerStep *pLast; /* Last element in link-list. Valid for 1st elem only */ }; +/* +** Information about a RETURNING clause +*/ +struct Returning { + Parse *pParse; /* The parse that includes the RETURNING clause */ + ExprList *pReturnEL; /* List of expressions to return */ + Trigger retTrig; /* The transient trigger that implements RETURNING */ + TriggerStep retTStep; /* The trigger step */ + Select retSel; /* The SELECT statement that implements RETURNING */ + u64 retSrcList; /* The empty FROM clause of the SELECT */ +}; + /* ** An objected used to accumulate the text of a string where we ** do not necessarily know how big the string will be in the end. diff --git a/src/trigger.c b/src/trigger.c index a9378fd3a3..5508e4d151 100644 --- a/src/trigger.c +++ b/src/trigger.c @@ -65,11 +65,16 @@ Trigger *sqlite3TriggerList(Parse *pParse, Table *pTab){ while( p ){ Trigger *pTrig = (Trigger *)sqliteHashData(p); if( pTrig->pTabSchema==pTab->pSchema - && 0==sqlite3StrICmp(pTrig->table, pTab->zName) + && 0==sqlite3StrICmp(pTrig->table, pTab->zName) ){ pTrig->pNext = pList; pList = pTrig; - } + }else if( pTrig->op==TK_RETURNING ){ + pTrig->table = pTab->zName; + pTrig->pTabSchema = pTab->pSchema; + pTrig->pNext = pList; + pList = pTrig; + } p = sqliteHashNext(p); } } @@ -405,6 +410,7 @@ TriggerStep *sqlite3TriggerSelectStep( return 0; } pTriggerStep->op = TK_SELECT; + pTriggerStep->eTrigDest = SRT_Discard; pTriggerStep->pSelect = pSelect; pTriggerStep->orconf = OE_Default; pTriggerStep->zSpan = triggerSpanDup(db, zStart, zEnd); @@ -563,6 +569,7 @@ TriggerStep *sqlite3TriggerDeleteStep( */ void sqlite3DeleteTrigger(sqlite3 *db, Trigger *pTrigger){ if( pTrigger==0 ) return; + assert( !pTrigger->bReturning ); sqlite3DeleteTriggerStep(db, pTrigger->step_list); sqlite3DbFree(db, pTrigger->zName); sqlite3DbFree(db, pTrigger->table); @@ -734,6 +741,9 @@ Trigger *sqlite3TriggersExist( for(p=pList; p; p=p->pNext){ if( p->op==op && checkColumnOverlap(p->pColumns, pChanges) ){ mask |= p->tr_tm; + }else if( p->op==TK_RETURNING ){ + p->op = op; + mask |= TRIGGER_AFTER; } } if( pMask ){ @@ -849,7 +859,7 @@ static int codeTriggerProgram( default: assert( pStep->op==TK_SELECT ); { SelectDest sDest; Select *pSelect = sqlite3SelectDup(db, pStep->pSelect, 0); - sqlite3SelectDestInit(&sDest, SRT_Discard, 0); + sqlite3SelectDestInit(&sDest, pStep->eTrigDest, 0); sqlite3Select(pParse, pSelect, &sDest); sqlite3SelectDelete(db, pSelect); break; @@ -947,6 +957,7 @@ static TriggerPrg *codeRowTrigger( pSubParse->pToplevel = pTop; pSubParse->zAuthContext = pTrigger->zName; pSubParse->eTriggerOp = pTrigger->op; + pSubParse->bReturning = pTrigger->bReturning; pSubParse->nQueryLoop = pParse->nQueryLoop; pSubParse->disableVtab = pParse->disableVtab; @@ -996,6 +1007,9 @@ static TriggerPrg *codeRowTrigger( if( db->mallocFailed==0 && pParse->nErr==0 ){ pProgram->aOp = sqlite3VdbeTakeOpArray(v, &pProgram->nOp, &pTop->nMaxArg); } + if( pTrigger->bReturning ){ + sqlite3VdbeColumnInfoXfer(pParse->pVdbe, v); + } pProgram->nMem = pSubParse->nMem; pProgram->nCsr = pSubParse->nTab; pProgram->token = (void *)pTrigger; diff --git a/src/vdbe.h b/src/vdbe.h index 17f11fdd77..48be53df7f 100644 --- a/src/vdbe.h +++ b/src/vdbe.h @@ -259,6 +259,7 @@ void sqlite3VdbeResetStepResult(Vdbe*); void sqlite3VdbeRewind(Vdbe*); int sqlite3VdbeReset(Vdbe*); void sqlite3VdbeSetNumCols(Vdbe*,int); +void sqlite3VdbeColumnInfoXfer(Vdbe*,Vdbe*); int sqlite3VdbeSetColName(Vdbe*, int, int, const char *, void(*)(void*)); void sqlite3VdbeCountChanges(Vdbe*); sqlite3 *sqlite3VdbeDb(Vdbe*); diff --git a/src/vdbeaux.c b/src/vdbeaux.c index 7b9b792054..9ea20628fe 100644 --- a/src/vdbeaux.c +++ b/src/vdbeaux.c @@ -2595,6 +2595,20 @@ void sqlite3VdbeSetNumCols(Vdbe *p, int nResColumn){ initMemArray(p->aColName, n, db, MEM_Null); } +/* +** Transfer the column count and name information from one Vdbe to +** another. +*/ +void sqlite3VdbeColumnInfoXfer(Vdbe *pTo, Vdbe *pFrom){ + sqlite3 *db = pTo->db; + assert( db==pFrom->db ); + sqlite3DbFree(db, pTo->aColName); + pTo->aColName = pFrom->aColName; + pFrom->aColName = 0; + pTo->nResColumn = pFrom->nResColumn; + pFrom->nResColumn = 0; +} + /* ** Set the name of the idx'th column to be returned by the SQL statement. ** zName must be a pointer to a nul terminated string. -- 2.47.2