insert.c

sqlite-source-2_8_16.zip 轻量级嵌入式数据库源码

** initially pointing to an entry that is being updated.  The isUpdate
** flag causes extra code to be generated so that the "base" cursor
** is still pointing at the same entry after the routine returns.
** Without the isUpdate flag, the "base" cursor might be moved.
*/
void sqliteGenerateConstraintChecks(
  Parse *pParse,      /* The parser context */
  Table *pTab,        /* the table into which we are inserting */
  int base,           /* Index of a read/write cursor pointing at pTab */
  char *aIdxUsed,     /* Which indices are used.  NULL means all are used */
  int recnoChng,      /* True if the record number will change */
  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 addr;
  int extra;
  int iCur;
  Index *pIdx;
  int seenReplace = 0;
  int jumpInst1, jumpInst2;
  int contAddr;
  int hasTwoRecnos = (isUpdate && recnoChng);

  v = sqliteGetVdbe(pParse);
  assert( v!=0 );
  assert( pTab->pSelect==0 );  /* This table is not a VIEW */
  nCol = pTab->nCol;

  /* 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( pParse->db->onError!=OE_Default ){
      onError = pParse->db->onError;
    }else if( onError==OE_Default ){
      onError = OE_Abort;
    }
    if( onError==OE_Replace && pTab->aCol[i].zDflt==0 ){
      onError = OE_Abort;
    }
    sqliteVdbeAddOp(v, OP_Dup, nCol-1-i, 1);
    addr = sqliteVdbeAddOp(v, OP_NotNull, 1, 0);
    switch( onError ){
      case OE_Rollback:
      case OE_Abort:
      case OE_Fail: {
        char *zMsg = 0;
        sqliteVdbeAddOp(v, OP_Halt, SQLITE_CONSTRAINT, onError);
        sqliteSetString(&zMsg, pTab->zName, ".", pTab->aCol[i].zName,
                        " may not be NULL", (char*)0);
        sqliteVdbeChangeP3(v, -1, zMsg, P3_DYNAMIC);
        break;
      }
      case OE_Ignore: {
        sqliteVdbeAddOp(v, OP_Pop, nCol+1+hasTwoRecnos, 0);
        sqliteVdbeAddOp(v, OP_Goto, 0, ignoreDest);
        break;
      }
      case OE_Replace: {
        sqliteVdbeOp3(v, OP_String, 0, 0, pTab->aCol[i].zDflt, P3_STATIC);
        sqliteVdbeAddOp(v, OP_Push, nCol-i, 0);
        break;
      }
      default: assert(0);
    }
    sqliteVdbeChangeP2(v, addr, sqliteVdbeCurrentAddr(v));
  }

  /* Test all CHECK constraints
  */
  /**** TBD ****/

  /* 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( recnoChng ){
    onError = pTab->keyConf;
    if( overrideError!=OE_Default ){
      onError = overrideError;
    }else if( pParse->db->onError!=OE_Default ){
      onError = pParse->db->onError;
    }else if( onError==OE_Default ){
      onError = OE_Abort;
    }
    
    if( isUpdate ){
      sqliteVdbeAddOp(v, OP_Dup, nCol+1, 1);
      sqliteVdbeAddOp(v, OP_Dup, nCol+1, 1);
      jumpInst1 = sqliteVdbeAddOp(v, OP_Eq, 0, 0);
    }
    sqliteVdbeAddOp(v, OP_Dup, nCol, 1);
    jumpInst2 = sqliteVdbeAddOp(v, OP_NotExists, base, 0);
    switch( onError ){
      default: {
        onError = OE_Abort;
        /* Fall thru into the next case */
      }
      case OE_Rollback:
      case OE_Abort:
      case OE_Fail: {
        sqliteVdbeOp3(v, OP_Halt, SQLITE_CONSTRAINT, onError,
                         "PRIMARY KEY must be unique", P3_STATIC);
        break;
      }
      case OE_Replace: {
        sqliteGenerateRowIndexDelete(pParse->db, v, pTab, base, 0);
        if( isUpdate ){
          sqliteVdbeAddOp(v, OP_Dup, nCol+hasTwoRecnos, 1);
          sqliteVdbeAddOp(v, OP_MoveTo, base, 0);
        }
        seenReplace = 1;
        break;
      }
      case OE_Ignore: {
        assert( seenReplace==0 );
        sqliteVdbeAddOp(v, OP_Pop, nCol+1+hasTwoRecnos, 0);
        sqliteVdbeAddOp(v, OP_Goto, 0, ignoreDest);
        break;
      }
    }
    contAddr = sqliteVdbeCurrentAddr(v);
    sqliteVdbeChangeP2(v, jumpInst2, contAddr);
    if( isUpdate ){
      sqliteVdbeChangeP2(v, jumpInst1, contAddr);
      sqliteVdbeAddOp(v, OP_Dup, nCol+1, 1);
      sqliteVdbeAddOp(v, OP_MoveTo, base, 0);
    }
  }

  /* 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.
  */
  extra = -1;
  for(iCur=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, iCur++){
    if( aIdxUsed && aIdxUsed[iCur]==0 ) continue;  /* Skip unused indices */
    extra++;

    /* Create a key for accessing the index entry */
    sqliteVdbeAddOp(v, OP_Dup, nCol+extra, 1);
    for(i=0; i<pIdx->nColumn; i++){
      int idx = pIdx->aiColumn[i];
      if( idx==pTab->iPKey ){
        sqliteVdbeAddOp(v, OP_Dup, i+extra+nCol+1, 1);
      }else{
        sqliteVdbeAddOp(v, OP_Dup, i+extra+nCol-idx, 1);
      }
    }
    jumpInst1 = sqliteVdbeAddOp(v, OP_MakeIdxKey, pIdx->nColumn, 0);
    if( pParse->db->file_format>=4 ) sqliteAddIdxKeyType(v, pIdx);

    /* 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( pParse->db->onError!=OE_Default ){
      onError = pParse->db->onError;
    }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 */
    sqliteVdbeAddOp(v, OP_Dup, extra+nCol+1+hasTwoRecnos, 1);
    jumpInst2 = sqliteVdbeAddOp(v, OP_IsUnique, base+iCur+1, 0);

    /* Generate code that executes if the new index entry is not unique */
    switch( onError ){
      case OE_Rollback:
      case OE_Abort:
      case OE_Fail: {
        int j, n1, n2;
        char zErrMsg[200];
        strcpy(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 ){
            strcpy(&zErrMsg[n1], ", ");
            n1 += 2;
          }
          if( n1+n2>sizeof(zErrMsg)-30 ){
            strcpy(&zErrMsg[n1], "...");
            n1 += 3;
            break;
          }else{
            strcpy(&zErrMsg[n1], zCol);
            n1 += n2;
          }
        }
        strcpy(&zErrMsg[n1], 
            pIdx->nColumn>1 ? " are not unique" : " is not unique");
        sqliteVdbeOp3(v, OP_Halt, SQLITE_CONSTRAINT, onError, zErrMsg, 0);
        break;
      }
      case OE_Ignore: {
        assert( seenReplace==0 );
        sqliteVdbeAddOp(v, OP_Pop, nCol+extra+3+hasTwoRecnos, 0);
        sqliteVdbeAddOp(v, OP_Goto, 0, ignoreDest);
        break;
      }
      case OE_Replace: {
        sqliteGenerateRowDelete(pParse->db, v, pTab, base, 0);
        if( isUpdate ){
          sqliteVdbeAddOp(v, OP_Dup, nCol+extra+1+hasTwoRecnos, 1);
          sqliteVdbeAddOp(v, OP_MoveTo, base, 0);
        }
        seenReplace = 1;
        break;
      }
      default: assert(0);
    }
    contAddr = sqliteVdbeCurrentAddr(v);
#if NULL_DISTINCT_FOR_UNIQUE
    sqliteVdbeChangeP2(v, jumpInst1, contAddr);
#endif
    sqliteVdbeChangeP2(v, jumpInst2, contAddr);
  }
}

/*
** This routine generates code to finish the INSERT or UPDATE operation
** that was started by a prior call to sqliteGenerateConstraintChecks.
** The stack must contain keys for all active indices followed by data
** and the recno for the new entry.  This routine creates the new
** entries in all indices and in the main table.
**
** The arguments to this routine should be the same as the first six
** arguments to sqliteGenerateConstraintChecks.
*/
void sqliteCompleteInsertion(
  Parse *pParse,      /* The parser context */
  Table *pTab,        /* the table into which we are inserting */
  int base,           /* Index of a read/write cursor pointing at pTab */
  char *aIdxUsed,     /* Which indices are used.  NULL means all are used */
  int recnoChng,      /* True if the record number will change */
  int isUpdate,       /* True for UPDATE, False for INSERT */
  int newIdx          /* Index of NEW table for triggers.  -1 if none */
){
  int i;
  Vdbe *v;
  int nIdx;
  Index *pIdx;

  v = sqliteGetVdbe(pParse);
  assert( v!=0 );
  assert( pTab->pSelect==0 );  /* This table is not a VIEW */
  for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){}
  for(i=nIdx-1; i>=0; i--){
    if( aIdxUsed && aIdxUsed[i]==0 ) continue;
    sqliteVdbeAddOp(v, OP_IdxPut, base+i+1, 0);
  }
  sqliteVdbeAddOp(v, OP_MakeRecord, pTab->nCol, 0);
  if( newIdx>=0 ){
    sqliteVdbeAddOp(v, OP_Dup, 1, 0);
    sqliteVdbeAddOp(v, OP_Dup, 1, 0);
    sqliteVdbeAddOp(v, OP_PutIntKey, newIdx, 0);
  }
  sqliteVdbeAddOp(v, OP_PutIntKey, base,
    (pParse->trigStack?0:OPFLAG_NCHANGE) |
    (isUpdate?0:OPFLAG_LASTROWID) | OPFLAG_CSCHANGE);
  if( isUpdate && recnoChng ){
    sqliteVdbeAddOp(v, OP_Pop, 1, 0);
  }
}

/*
** Generate code that will open write cursors for a table and for all
** indices of that table.  The "base" parameter is the cursor number used
** for the table.  Indices are opened on subsequent cursors.
**
** Return the total number of cursors opened.  This is always at least
** 1 (for the main table) plus more for each cursor.
*/
int sqliteOpenTableAndIndices(Parse *pParse, Table *pTab, int base){
  int i;
  Index *pIdx;
  Vdbe *v = sqliteGetVdbe(pParse);
  assert( v!=0 );
  sqliteVdbeAddOp(v, OP_Integer, pTab->iDb, 0);
  sqliteVdbeOp3(v, OP_OpenWrite, base, pTab->tnum, pTab->zName, P3_STATIC);
  for(i=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
    sqliteVdbeAddOp(v, OP_Integer, pIdx->iDb, 0);
    sqliteVdbeOp3(v, OP_OpenWrite, i+base, pIdx->tnum, pIdx->zName, P3_STATIC);
  }
  return i;
}