insert.c

SQLite is a software library that implements a self-contained, serverless, zero-configuration, trans

      }else if( pSelect ){
        sqlite3VdbeAddOp2(v, OP_SCopy, regFromSelect+j, iRegStore);
      }else{
        sqlite3ExprCode(pParse, pList->a[j].pExpr, iRegStore);
      }
    }

    /* Generate code to check constraints and generate index keys and
    ** do the insertion.
    */
#ifndef SQLITE_OMIT_VIRTUALTABLE
    if( IsVirtual(pTab) ){
      pParse->pVirtualLock = pTab;
      sqlite3VdbeAddOp4(v, OP_VUpdate, 1, pTab->nCol+2, regIns,
                     (const char*)pTab->pVtab, P4_VTAB);
    }else
#endif
    {
      sqlite3GenerateConstraintChecks(
          pParse,
          pTab,
          baseCur,
          regIns,
          aRegIdx,
          keyColumn>=0,
          0,
          onError,
          endOfLoop
      );
      sqlite3CompleteInsertion(
          pParse,
          pTab,
          baseCur,
          regIns,
          aRegIdx,
          0,
          0,
          (triggers_exist & TRIGGER_AFTER)!=0 ? newIdx : -1,
          appendFlag
       );
    }
  }

  /* Update the count of rows that are inserted
  */
  if( (db->flags & SQLITE_CountRows)!=0 ){
    sqlite3VdbeAddOp2(v, OP_AddImm, regRowCount, 1);
  }

  if( triggers_exist ){
    /* Code AFTER triggers */
    if( sqlite3CodeRowTrigger(pParse, TK_INSERT, 0, TRIGGER_AFTER, pTab,
          newIdx, -1, onError, endOfLoop, 0, 0) ){
      goto insert_cleanup;
    }
  }

  /* The bottom of the loop, if the data source is a SELECT statement
  */
  sqlite3VdbeResolveLabel(v, endOfLoop);
  if( useTempTable ){
    sqlite3VdbeAddOp2(v, OP_Next, srcTab, iCont);
    sqlite3VdbeResolveLabel(v, iBreak);
    sqlite3VdbeAddOp2(v, OP_Close, srcTab, 0);
  }else if( pSelect ){
    sqlite3VdbeAddOp2(v, OP_Return, 0, 0);
    sqlite3VdbeResolveLabel(v, iCleanup);
  }

  if( !IsVirtual(pTab) && !isView ){
    /* Close all tables opened */
    sqlite3VdbeAddOp2(v, OP_Close, baseCur, 0);
    for(idx=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, idx++){
      sqlite3VdbeAddOp2(v, OP_Close, idx+baseCur, 0);
    }
  }

  /* Update the sqlite_sequence table by storing the content of the
  ** counter value in memory regAutoinc back into the sqlite_sequence
  ** table.
  */
  autoIncEnd(pParse, iDb, pTab, regAutoinc);

  /*
  ** Return the number of rows inserted. If this routine is 
  ** generating code because of a call to sqlite3NestedParse(), do not
  ** invoke the callback function.
  */
  if( db->flags & SQLITE_CountRows && pParse->nested==0 && !pParse->trigStack ){
    sqlite3VdbeAddOp2(v, OP_ResultRow, regRowCount, 1);
    sqlite3VdbeSetNumCols(v, 1);
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows inserted", P4_STATIC);
  }

insert_cleanup:
  sqlite3SrcListDelete(pTabList);
  sqlite3ExprListDelete(pList);
  sqlite3SelectDelete(pSelect);
  sqlite3IdListDelete(pColumn);
  sqlite3_free(aRegIdx);
}

/*
** Generate code to do constraint checks prior to an INSERT or an UPDATE.
**
** The input is a range of consecutive registers as follows:
**
**    1.  The rowid of the row to be updated before the update.  This
**        value is omitted unless we are doing an UPDATE that involves a
**        change to the record number or writing to a virtual table.
**
**    2.  The rowid of the row after the update.
**
**    3.  The data in the first column of the entry after the update.
**
**    i.  Data from middle columns...
**
**    N.  The data in the last column of the entry after the update.
**
** The regRowid parameter is the index of the register containing (2).
**
** The old rowid shown as entry (1) above is omitted unless both isUpdate
** and rowidChng are 1.  isUpdate is true for UPDATEs and false for
** INSERTs.  RowidChng means that the new rowid is explicitly specified by
** the update or insert statement.  If rowidChng is false, it means that
** the rowid is computed automatically in an insert or that the rowid value
** is not modified by the update.
**
** The code generated by this routine store new index entries into
** registers identified by aRegIdx[].  No index entry is created for
** indices where aRegIdx[i]==0.  The order of indices in aRegIdx[] is
** the same as the order of indices on the linked list of indices
** attached to the table.
**
** This routine also generates code to check constraints.  NOT NULL,
** CHECK, and UNIQUE constraints are all checked.  If a constraint fails,
** then the appropriate action is performed.  There are five possible
** actions: ROLLBACK, ABORT, FAIL, REPLACE, and IGNORE.
**
**  Constraint type  Action       What Happens
**  ---------------  ----------   ----------------------------------------
**  any              ROLLBACK     The current transaction is rolled back and
**                                sqlite3_exec() returns immediately with a
**                                return code of SQLITE_CONSTRAINT.
**
**  any              ABORT        Back out changes from the current command
**                                only (do not do a complete rollback) then
**                                cause sqlite3_exec() to return immediately
**                                with SQLITE_CONSTRAINT.
**
**  any              FAIL         Sqlite_exec() returns immediately with a
**                                return code of SQLITE_CONSTRAINT.  The
**                                transaction is not rolled back and any
**                                prior changes are retained.
**
**  any              IGNORE       The record number and data is popped from
**                                the stack and there is an immediate jump
**                                to label ignoreDest.
**
**  NOT NULL         REPLACE      The NULL value is replace by the default
**                                value for that column.  If the default value
**                                is NULL, the action is the same as ABORT.
**
**  UNIQUE           REPLACE      The other row that conflicts with the row
**                                being inserted is removed.
**
**  CHECK            REPLACE      Illegal.  The results in an exception.
**
** Which action to take is determined by the overrideError parameter.
** Or if overrideError==OE_Default, then the pParse->onError parameter
** is used.  Or if pParse->onError==OE_Default then the onError value
** for the constraint is used.
**
** The calling routine must open a read/write cursor for pTab with
** cursor number "baseCur".  All indices of pTab must also have open
** read/write cursors with cursor number baseCur+i for the i-th cursor.
** Except, if there is no possibility of a REPLACE action then
** cursors do not need to be open for indices where aRegIdx[i]==0.
*/
void sqlite3GenerateConstraintChecks(
  Parse *pParse,      /* The parser context */
  Table *pTab,        /* the table into which we are inserting */
  int baseCur,        /* Index of a read/write cursor pointing at pTab */
  int regRowid,       /* Index of the range of input registers */
  int *aRegIdx,       /* Register used by each index.  0 for unused indices */
  int rowidChng,      /* True if the rowid might collide with existing entry */
  int isUpdate,       /* True for UPDATE, False for INSERT */
  int overrideError,  /* Override onError to this if not OE_Default */
  int ignoreDest      /* Jump to this label on an OE_Ignore resolution */
){
  int i;
  Vdbe *v;
  int nCol;
  int onError;
  int j1, j2, j3;     /* Addresses of jump instructions */
  int regData;        /* Register containing first data column */
  int iCur;
  Index *pIdx;
  int seenReplace = 0;
  int hasTwoRowids = (isUpdate && rowidChng);

  v = sqlite3GetVdbe(pParse);
  assert( v!=0 );
  assert( pTab->pSelect==0 );  /* This table is not a VIEW */
  nCol = pTab->nCol;
  regData = regRowid + 1;


  /* Test all NOT NULL constraints.
  */
  for(i=0; i<nCol; i++){
    if( i==pTab->iPKey ){
      continue;
    }
    onError = pTab->aCol[i].notNull;
    if( onError==OE_None ) continue;
    if( overrideError!=OE_Default ){
      onError = overrideError;
    }else if( onError==OE_Default ){
      onError = OE_Abort;
    }
    if( onError==OE_Replace && pTab->aCol[i].pDflt==0 ){
      onError = OE_Abort;
    }
    j1 = sqlite3VdbeAddOp1(v, OP_NotNull, regData+i);
    assert( onError==OE_Rollback || onError==OE_Abort || onError==OE_Fail
        || onError==OE_Ignore || onError==OE_Replace );
    switch( onError ){
      case OE_Rollback:
      case OE_Abort:
      case OE_Fail: {
        char *zMsg = 0;
        sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_CONSTRAINT, onError);
        sqlite3SetString(&zMsg, pTab->zName, ".", pTab->aCol[i].zName,
                        " may not be NULL", (char*)0);
        sqlite3VdbeChangeP4(v, -1, zMsg, P4_DYNAMIC);
        break;
      }
      case OE_Ignore: {
        sqlite3VdbeAddOp2(v, OP_Goto, 0, ignoreDest);
        break;
      }
      case OE_Replace: {
        sqlite3ExprCode(pParse, pTab->aCol[i].pDflt, regData+i);
        break;
      }
    }
    sqlite3VdbeJumpHere(v, j1);
  }

  /* Test all CHECK constraints
  */
#ifndef SQLITE_OMIT_CHECK
  if( pTab->pCheck && (pParse->db->flags & SQLITE_IgnoreChecks)==0 ){
    int allOk = sqlite3VdbeMakeLabel(v);
    pParse->ckBase = regData;
    sqlite3ExprIfTrue(pParse, pTab->pCheck, allOk, SQLITE_JUMPIFNULL);
    onError = overrideError!=OE_Default ? overrideError : OE_Abort;
    if( onError==OE_Ignore ){
      sqlite3VdbeAddOp2(v, OP_Goto, 0, ignoreDest);
    }else{
      sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_CONSTRAINT, onError);
    }
    sqlite3VdbeResolveLabel(v, allOk);
  }
#endif /* !defined(SQLITE_OMIT_CHECK) */

  /* If we have an INTEGER PRIMARY KEY, make sure the primary key
  ** of the new record does not previously exist.  Except, if this
  ** is an UPDATE and the primary key is not changing, that is OK.
  */
  if( rowidChng ){
    onError = pTab->keyConf;
    if( overrideError!=OE_Default ){
      onError = overrideError;
    }else if( onError==OE_Default ){
      onError = OE_Abort;
    }
    
    if( onError!=OE_Replace || pTab->pIndex ){
      if( isUpdate ){
        j2 = sqlite3VdbeAddOp3(v, OP_Eq, regRowid, 0, regRowid-1);
      }
      j3 = sqlite3VdbeAddOp3(v, OP_NotExists, baseCur, 0, regRowid);
      switch( onError ){
        default: {
          onError = OE_Abort;
          /* Fall thru into the next case */
        }
        case OE_Rollback:
        case OE_Abort:
        case OE_Fail: {
          sqlite3VdbeAddOp4(v, OP_Halt, SQLITE_CONSTRAINT, onError, 0,
                           "PRIMARY KEY must be unique", P4_STATIC);
          break;
        }
        case OE_Replace: {
          sqlite3GenerateRowIndexDelete(pParse, pTab, baseCur, 0);
          seenReplace = 1;
          break;
        }
        case OE_Ignore: {
          assert( seenReplace==0 );
          sqlite3VdbeAddOp2(v, OP_Goto, 0, ignoreDest);
          break;
        }
      }
      sqlite3VdbeJumpHere(v, j3);
      if( isUpdate ){
        sqlite3VdbeJumpHere(v, j2);
      }
    }
  }

  /* Test all UNIQUE constraints by creating entries for each UNIQUE
  ** index and making sure that duplicate entries do not already exist.
  ** Add the new records to the indices as we go.
  */
  for(iCur=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, iCur++){
    int regIdx;
    int regR;

    if( aRegIdx[iCur]==0 ) continue;  /* Skip unused indices */

    /* Create a key for accessing the index entry */
    regIdx = sqlite3GetTempRange(pParse, pIdx->nColumn+1);
    for(i=0; i<pIdx->nColumn; i++){
      int idx = pIdx->aiColumn[i];
      if( idx==pTab->iPKey ){
        sqlite3VdbeAddOp2(v, OP_SCopy, regRowid, regIdx+i);
      }else{
        sqlite3VdbeAddOp2(v, OP_SCopy, regData+idx, regIdx+i);
      }
    }
    sqlite3VdbeAddOp2(v, OP_SCopy, regRowid, regIdx+i);
    sqlite3VdbeAddOp3(v, OP_MakeRecord, regIdx, pIdx->nColumn+1, aRegIdx[iCur]);
    sqlite3IndexAffinityStr(v, pIdx);
    sqlite3ExprCacheAffinityChange(pParse, regIdx, pIdx->nColumn+1);
    sqlite3ReleaseTempRange(pParse, regIdx, pIdx->nColumn+1);

    /* Find out what action to take in case there is an indexing conflict */
    onError = pIdx->onError;
    if( onError==OE_None ) continue;  /* pIdx is not a UNIQUE index */
    if( overrideError!=OE_Default ){
      onError = overrideError;
    }else if( onError==OE_Default ){
      onError = OE_Abort;
    }
    if( seenReplace ){
      if( onError==OE_Ignore ) onError = OE_Replace;
      else if( onError==OE_Fail ) onError = OE_Abort;
    }
    

    /* Check to see if the new index entry will be unique */
    j2 = sqlite3VdbeAddOp3(v, OP_IsNull, regIdx, 0, pIdx->nColumn);
    regR = sqlite3GetTempReg(pParse);
    sqlite3VdbeAddOp2(v, OP_SCopy, regRowid-hasTwoRowids, regR);
    j3 = sqlite3VdbeAddOp4(v, OP_IsUnique, baseCur+iCur+1, 0,
                           regR, (char*)(sqlite3_intptr_t)aRegIdx[iCur],
                           P4_INT32);

    /* Generate code that executes if the new index entry is not unique */
    assert( onError==OE_Rollback || onError==OE_Abort || onError==OE_Fail
        || onError==OE_Ignore || onError==OE_Replace );
    switch( onError ){
      case OE_Rollback:
      case OE_Abort:
      case OE_Fail: {
        int j, n1, n2;
        char zErrMsg[200];
        sqlite3_snprintf(sizeof(zErrMsg), zErrMsg,
                         pIdx->nColumn>1 ? "columns " : "column ");
        n1 = strlen(zErrMsg);
        for(j=0; j<pIdx->nColumn && n1<sizeof(zErrMsg)-30; j++){
          char *zCol = pTab->aCol[pIdx->aiColumn[j]].zName;
          n2 = strlen(zCol);
          if( j>0 ){
            sqlite3_snprintf(sizeof(zErrMsg)-n1, &zErrMsg[n1], ", ");
            n1 += 2;
          }
          if( n1+n2>sizeof(zErrMsg)-30 ){
            sqlite3_snprintf(sizeof(zErrMsg)-n1, &zErrMsg[n1], "...");
            n1 += 3;
            break;
          }else{
            sqlite3_snprintf(sizeof(zErrMsg)-n1, &zErrMsg[n1], "%s", zCol);
            n1 += n2;
          }
        }
        sqlite3_snprintf(sizeof(zErrMsg)-n1, &zErrMsg[n1], 
            pIdx->nColumn>1 ? " are not unique" : " is not unique");
        sqlite3VdbeAddOp4(v, OP_Halt, SQLITE_CONSTRAINT, onError, 0, zErrMsg,0);
        break;
      }
      case OE_Ignore: {
        assert( seenReplace==0 );
        sqlite3VdbeAddOp2(v, OP_Goto, 0, ignoreDest);
        break;
      }
      case OE_Replace: {
        sqlite3GenerateRowDelete(pParse, pTab, baseCur, regR, 0);
        seenReplace = 1;
        break;
      }
    }
    sqlite3VdbeJumpHere(v, j2);
    sqlite3VdbeJumpHere(v, j3);
    sqlite3ReleaseTempReg(pParse, regR);
  }
}

/*
** This routine generates code to finish the INSERT or UPDATE operation
** that was started by a prior call to sqlite3GenerateConstraintChecks.
** A consecutive range of registers starting at regRowid contains the
** rowid and the content to be inserted.
**