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Overview
Comment:Only support the magic "__hidden__" column name prefix interpretation when compiled with SQLITE_ENABLE_HIDDEN_COLUMNS.
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SHA1:5490646b2eb74ea8bd5ab2690f69b9c707a0165f
User & Date: drh 2015-11-19 13:53:57
Context
2015-11-19
14:11
If compiled with SQLITE_ENABLE_HIDDEN_COLUMNS, then columns in ordinary tables and views that have names beginning with "__hidden__" are omitted from the "*" expansion in SELECT statements and from the automatic list of columns following the table name in an INSERT INTO statement. check-in: 011904ca user: drh tags: trunk
13:53
Only support the magic "__hidden__" column name prefix interpretation when compiled with SQLITE_ENABLE_HIDDEN_COLUMNS. Closed-Leaf check-in: 5490646b user: drh tags: hidden-columns-in-tables
2015-11-18
21:22
Get the __hidden__ column mechanism working on views with INSTEAD OF triggers. check-in: 20c1e9ce user: drh tags: hidden-columns-in-tables
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to src/build.c.

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  return;

  /* If an error occurs, we jump here */
begin_table_error:
  sqlite3DbFree(db, zName);
  return;
}













/*
** This macro is used to compare two strings in a case-insensitive manner.
** It is slightly faster than calling sqlite3StrICmp() directly, but
** produces larger code.
**
** WARNING: This macro is not compatible with the strcmp() family. It
................................................................................
      return;
    }
    p->aCol = aNew;
  }
  pCol = &p->aCol[p->nCol];
  memset(pCol, 0, sizeof(p->aCol[0]));
  pCol->zName = z;
  if( sqlite3_strnicmp(z, "__hidden__", 10)==0 ){
    pCol->colFlags |= COLFLAG_HIDDEN;
  }
 
  /* If there is no type specified, columns have the default affinity
  ** 'BLOB'. If there is a type specified, then sqlite3AddColumnType() will
  ** be called next to set pCol->affinity correctly.
  */
  pCol->affinity = SQLITE_AFF_BLOB;
  pCol->szEst = 1;







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  return;

  /* If an error occurs, we jump here */
begin_table_error:
  sqlite3DbFree(db, zName);
  return;
}

/* Set properties of a table column based on the (magical)
** name of the column.
*/
void sqlite3ColumnPropertiesFromName(Column *pCol){
#if SQLITE_ENABLE_HIDDEN_COLUMNS
  if( sqlite3_strnicmp(pCol->zName, "__hidden__", 10)==0 ){
    pCol->colFlags |= COLFLAG_HIDDEN;
  }
#endif
}


/*
** This macro is used to compare two strings in a case-insensitive manner.
** It is slightly faster than calling sqlite3StrICmp() directly, but
** produces larger code.
**
** WARNING: This macro is not compatible with the strcmp() family. It
................................................................................
      return;
    }
    p->aCol = aNew;
  }
  pCol = &p->aCol[p->nCol];
  memset(pCol, 0, sizeof(p->aCol[0]));
  pCol->zName = z;
  sqlite3ColumnPropertiesFromName(pCol);


 
  /* If there is no type specified, columns have the default affinity
  ** 'BLOB'. If there is a type specified, then sqlite3AddColumnType() will
  ** be called next to set pCol->affinity correctly.
  */
  pCol->affinity = SQLITE_AFF_BLOB;
  pCol->szEst = 1;

Changes to src/insert.c.

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    for(i=j=0; i<pTab->nCol; i++){
      if( pColumn ){
        for(j=0; j<pColumn->nId; j++){
          if( pColumn->a[j].idx==i ) break;
        }
      }
      if( (!useTempTable && !pList) || (pColumn && j>=pColumn->nId)
            || (pColumn==0 && IsHiddenColumn(&pTab->aCol[i])) ){
        sqlite3ExprCode(pParse, pTab->aCol[i].pDflt, regCols+i+1);
      }else if( useTempTable ){
        sqlite3VdbeAddOp3(v, OP_Column, srcTab, j, regCols+i+1); 
      }else{
        assert( pSelect==0 ); /* Otherwise useTempTable is true */
        sqlite3ExprCodeAndCache(pParse, pList->a[j].pExpr, regCols+i+1);
      }
      if( pColumn==0 && !IsHiddenColumn(&pTab->aCol[i]) ) j++;
    }

    /* If this is an INSERT on a view with an INSTEAD OF INSERT trigger,
    ** do not attempt any conversions before assembling the record.
    ** If this is a real table, attempt conversions as required by the
    ** table column affinities.
    */
................................................................................
        ** taking up data space with information that will never be used.
        ** As there may be shallow copies of this value, make it a soft-NULL */
        sqlite3VdbeAddOp1(v, OP_SoftNull, iRegStore);
        continue;
      }
      if( pColumn==0 ){
        if( IsHiddenColumn(&pTab->aCol[i]) ){
          assert( IsVirtual(pTab)
                || sqlite3_strnicmp(pTab->aCol[i].zName,"__hidden__",10)==0 );
          j = -1;
          nHidden++;
        }else{
          j = i - nHidden;
        }
      }else{
        for(j=0; j<pColumn->nId; j++){







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    for(i=j=0; i<pTab->nCol; i++){
      if( pColumn ){
        for(j=0; j<pColumn->nId; j++){
          if( pColumn->a[j].idx==i ) break;
        }
      }
      if( (!useTempTable && !pList) || (pColumn && j>=pColumn->nId)
            || (pColumn==0 && IsOrdinaryHiddenColumn(&pTab->aCol[i])) ){
        sqlite3ExprCode(pParse, pTab->aCol[i].pDflt, regCols+i+1);
      }else if( useTempTable ){
        sqlite3VdbeAddOp3(v, OP_Column, srcTab, j, regCols+i+1); 
      }else{
        assert( pSelect==0 ); /* Otherwise useTempTable is true */
        sqlite3ExprCodeAndCache(pParse, pList->a[j].pExpr, regCols+i+1);
      }
      if( pColumn==0 && !IsOrdinaryHiddenColumn(&pTab->aCol[i]) ) j++;
    }

    /* If this is an INSERT on a view with an INSTEAD OF INSERT trigger,
    ** do not attempt any conversions before assembling the record.
    ** If this is a real table, attempt conversions as required by the
    ** table column affinities.
    */
................................................................................
        ** taking up data space with information that will never be used.
        ** As there may be shallow copies of this value, make it a soft-NULL */
        sqlite3VdbeAddOp1(v, OP_SoftNull, iRegStore);
        continue;
      }
      if( pColumn==0 ){
        if( IsHiddenColumn(&pTab->aCol[i]) ){


          j = -1;
          nHidden++;
        }else{
          j = i - nHidden;
        }
      }else{
        for(j=0; j<pColumn->nId; j++){

Changes to src/select.c.

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        for(j=nName-1; j>0 && sqlite3Isdigit(zName[j]); j--){}
        if( zName[j]==':' ) nName = j;
      }
      zName = sqlite3MPrintf(db, "%.*z:%u", nName, zName, ++cnt);
      if( cnt>3 ) sqlite3_randomness(sizeof(cnt), &cnt);
    }
    pCol->zName = zName;
    if( zName ){
      if( sqlite3HashInsert(&ht, zName, pCol)==pCol ){
        db->mallocFailed = 1;
      }else if( sqlite3_strnicmp(zName, "__hidden__", 10)==0 ){
        pCol->colFlags |= COLFLAG_HIDDEN;
      }
    }
  }
  sqlite3HashClear(&ht);
  if( db->mallocFailed ){
    for(j=0; j<i; j++){
      sqlite3DbFree(db, aCol[j].zName);
    }
................................................................................
            assert( zName );
            if( zTName && pSub
             && sqlite3MatchSpanName(pSub->pEList->a[j].zSpan, 0, zTName, 0)==0
            ){
              continue;
            }

            /* If a column is marked as 'hidden' (currently only possible
            ** for virtual tables), do not include it in the expanded
            ** result-set list.
            */
            if( IsHiddenColumn(&pTab->aCol[j]) ){
              assert( IsVirtual(pTab)
               || sqlite3_strnicmp(pTab->aCol[j].zName,"__hidden__", 10)==0 );
              continue;
            }
            tableSeen = 1;

            if( i>0 && zTName==0 ){
              if( (pFrom->fg.jointype & JT_NATURAL)!=0
                && tableAndColumnIndex(pTabList, i, zName, 0, 0)







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        for(j=nName-1; j>0 && sqlite3Isdigit(zName[j]); j--){}
        if( zName[j]==':' ) nName = j;
      }
      zName = sqlite3MPrintf(db, "%.*z:%u", nName, zName, ++cnt);
      if( cnt>3 ) sqlite3_randomness(sizeof(cnt), &cnt);
    }
    pCol->zName = zName;
    sqlite3ColumnPropertiesFromName(pCol);
    if( zName && sqlite3HashInsert(&ht, zName, pCol)==pCol ){
      db->mallocFailed = 1;



    }
  }
  sqlite3HashClear(&ht);
  if( db->mallocFailed ){
    for(j=0; j<i; j++){
      sqlite3DbFree(db, aCol[j].zName);
    }
................................................................................
            assert( zName );
            if( zTName && pSub
             && sqlite3MatchSpanName(pSub->pEList->a[j].zSpan, 0, zTName, 0)==0
            ){
              continue;
            }

            /* If a column is marked as 'hidden', do not include it in

            ** the expanded result-set list.
            */
            if( IsHiddenColumn(&pTab->aCol[j]) ){


              continue;
            }
            tableSeen = 1;

            if( i>0 && zTName==0 ){
              if( (pFrom->fg.jointype & JT_NATURAL)!=0
                && tableAndColumnIndex(pTabList, i, zName, 0, 0)

Changes to src/sqliteInt.h.

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/*
** Test to see whether or not a table is a virtual table.  This is
** done as a macro so that it will be optimized out when virtual
** table support is omitted from the build.
*/
#ifndef SQLITE_OMIT_VIRTUALTABLE
#  define IsVirtual(X)      (((X)->tabFlags & TF_Virtual)!=0)
#  define IsHiddenColumn(X) (((X)->colFlags & COLFLAG_HIDDEN)!=0)
#else
#  define IsVirtual(X)      0
#  define IsHiddenColumn(X) 0
#endif



















/* Does the table have a rowid */
#define HasRowid(X)     (((X)->tabFlags & TF_WithoutRowid)==0)
#define VisibleRowid(X) (((X)->tabFlags & TF_NoVisibleRowid)==0)

/*
** Each foreign key constraint is an instance of the following structure.
................................................................................
void sqlite3DeleteColumnNames(sqlite3*,Table*);
int sqlite3ColumnsFromExprList(Parse*,ExprList*,i16*,Column**);
Table *sqlite3ResultSetOfSelect(Parse*,Select*);
void sqlite3OpenMasterTable(Parse *, int);
Index *sqlite3PrimaryKeyIndex(Table*);
i16 sqlite3ColumnOfIndex(Index*, i16);
void sqlite3StartTable(Parse*,Token*,Token*,int,int,int,int);

void sqlite3AddColumn(Parse*,Token*);
void sqlite3AddNotNull(Parse*, int);
void sqlite3AddPrimaryKey(Parse*, ExprList*, int, int, int);
void sqlite3AddCheckConstraint(Parse*, Expr*);
void sqlite3AddColumnType(Parse*,Token*);
void sqlite3AddDefaultValue(Parse*,ExprSpan*);
void sqlite3AddCollateType(Parse*, Token*);







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/*
** Test to see whether or not a table is a virtual table.  This is
** done as a macro so that it will be optimized out when virtual
** table support is omitted from the build.
*/
#ifndef SQLITE_OMIT_VIRTUALTABLE
#  define IsVirtual(X)      (((X)->tabFlags & TF_Virtual)!=0)

#else
#  define IsVirtual(X)      0
#  define IsHiddenColumn(X) 0
#endif

/*
** Macros to determine if a column is hidden.  IsOrdinaryHiddenColumn()
** only works for non-virtual tables (ordinary tables and views) and is
** always false unless SQLITE_ENABLE_HIDDEN_COLUMNS is defined.  The
** IsHiddenColumn() macro is general purpose.
*/
#if defined(SQLITE_ENABLE_HIDDEN_COLUMNS)
#  define IsHiddenColumn(X)         (((X)->colFlags & COLFLAG_HIDDEN)!=0)
#  define IsOrdinaryHiddenColumn(X) (((X)->colFlags & COLFLAG_HIDDEN)!=0)
#elif !defined(SQLITE_OMIT_VIRTUAL)
#  define IsHiddenColumn(X)         (((X)->colFlags & COLFLAG_HIDDEN)!=0)
#  define IsOrdinaryHiddenColumn(X) 0
#else
#  define IsHiddenColumn(X)         0
#  define IsOrdinaryHiddenColumn(X) 0
#endif


/* Does the table have a rowid */
#define HasRowid(X)     (((X)->tabFlags & TF_WithoutRowid)==0)
#define VisibleRowid(X) (((X)->tabFlags & TF_NoVisibleRowid)==0)

/*
** Each foreign key constraint is an instance of the following structure.
................................................................................
void sqlite3DeleteColumnNames(sqlite3*,Table*);
int sqlite3ColumnsFromExprList(Parse*,ExprList*,i16*,Column**);
Table *sqlite3ResultSetOfSelect(Parse*,Select*);
void sqlite3OpenMasterTable(Parse *, int);
Index *sqlite3PrimaryKeyIndex(Table*);
i16 sqlite3ColumnOfIndex(Index*, i16);
void sqlite3StartTable(Parse*,Token*,Token*,int,int,int,int);
void sqlite3ColumnPropertiesFromName(Column*);
void sqlite3AddColumn(Parse*,Token*);
void sqlite3AddNotNull(Parse*, int);
void sqlite3AddPrimaryKey(Parse*, ExprList*, int, int, int);
void sqlite3AddCheckConstraint(Parse*, Expr*);
void sqlite3AddColumnType(Parse*,Token*);
void sqlite3AddDefaultValue(Parse*,ExprSpan*);
void sqlite3AddCollateType(Parse*, Token*);

Changes to src/test_config.c.

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#endif

#ifdef SQLITE_ENABLE_CURSOR_HINTS
  Tcl_SetVar2(interp, "sqlite_options", "cursorhints", "1", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "cursorhints", "0", TCL_GLOBAL_ONLY);
#endif







#ifdef SQLITE_ENABLE_MEMSYS3
  Tcl_SetVar2(interp, "sqlite_options", "mem3", "1", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "mem3", "0", TCL_GLOBAL_ONLY);
#endif








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#endif

#ifdef SQLITE_ENABLE_CURSOR_HINTS
  Tcl_SetVar2(interp, "sqlite_options", "cursorhints", "1", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "cursorhints", "0", TCL_GLOBAL_ONLY);
#endif

#ifdef SQLITE_ENABLE_HIDDEN_COLUMNS
  Tcl_SetVar2(interp, "sqlite_options", "hiddencolumns", "1", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "hiddencolumns", "0", TCL_GLOBAL_ONLY);
#endif

#ifdef SQLITE_ENABLE_MEMSYS3
  Tcl_SetVar2(interp, "sqlite_options", "mem3", "1", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "mem3", "0", TCL_GLOBAL_ONLY);
#endif

Changes to test/hidden.test.

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#
# Test the __hidden__ hack.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix hidden






do_execsql_test 1.1 {
  CREATE TABLE t1(__hidden__a, b);
  INSERT INTO t1 VALUES('1');
  INSERT INTO t1(__hidden__a, b) VALUES('x', 'y');
} {}

................................................................................
  } {1 2 3 4 5 {}}
  
  do_execsql_test 2.$tn.5 {
    INSERT INTO v1(a, b, __hidden__c) VALUES(7, 8, 9);
    SELECT * FROM x1;
  } {1 2 3 4 5 {} 7 8 9}
}




  
finish_test







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#
# Test the __hidden__ hack.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix hidden

ifcapable !hiddencolumns {
  finish_test
  return
}

do_execsql_test 1.1 {
  CREATE TABLE t1(__hidden__a, b);
  INSERT INTO t1 VALUES('1');
  INSERT INTO t1(__hidden__a, b) VALUES('x', 'y');
} {}

................................................................................
  } {1 2 3 4 5 {}}
  
  do_execsql_test 2.$tn.5 {
    INSERT INTO v1(a, b, __hidden__c) VALUES(7, 8, 9);
    SELECT * FROM x1;
  } {1 2 3 4 5 {} 7 8 9}
}
  




finish_test

Changes to test/releasetest.tcl.

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    -DSQLITE_TCL_DEFAULT_FULLMUTEX=1
    -DSQLITE_ENABLE_FTS3=1
    -DSQLITE_ENABLE_RTREE=1
    -DSQLITE_ENABLE_MEMSYS5=1
    -DSQLITE_ENABLE_MEMSYS3=1
    -DSQLITE_ENABLE_COLUMN_METADATA=1
    -DSQLITE_ENABLE_STAT4

    -DSQLITE_MAX_ATTACHED=125
  }
  "Fast-One" {
    -O6
    -DSQLITE_ENABLE_FTS4=1
    -DSQLITE_ENABLE_RTREE=1
    -DSQLITE_ENABLE_STAT4
................................................................................
    -DSQLITE_ENABLE_ATOMIC_WRITE=1
    -DSQLITE_ENABLE_IOTRACE=1
    -DSQLITE_ENABLE_MEMORY_MANAGEMENT=1
    -DSQLITE_MAX_PAGE_SIZE=4096
    -DSQLITE_OMIT_LOAD_EXTENSION=1
    -DSQLITE_OMIT_PROGRESS_CALLBACK=1
    -DSQLITE_OMIT_VIRTUALTABLE=1

    -DSQLITE_TEMP_STORE=3
    --enable-json1
  }
  "Device-Two" {
    -DSQLITE_4_BYTE_ALIGNED_MALLOC=1
    -DSQLITE_DEFAULT_AUTOVACUUM=1
    -DSQLITE_DEFAULT_CACHE_SIZE=1000
................................................................................
    -DSQLITE_OMIT_LOOKASIDE=1
    -DHAVE_USLEEP=1
  }
  "Valgrind" {
    -DSQLITE_ENABLE_STAT4
    -DSQLITE_ENABLE_FTS4
    -DSQLITE_ENABLE_RTREE

    --enable-json1
  }

  # The next group of configurations are used only by the
  # Failure-Detection platform.  They are all the same, but we need
  # different names for them all so that they results appear in separate
  # subdirectories.







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    -DSQLITE_TCL_DEFAULT_FULLMUTEX=1
    -DSQLITE_ENABLE_FTS3=1
    -DSQLITE_ENABLE_RTREE=1
    -DSQLITE_ENABLE_MEMSYS5=1
    -DSQLITE_ENABLE_MEMSYS3=1
    -DSQLITE_ENABLE_COLUMN_METADATA=1
    -DSQLITE_ENABLE_STAT4
    -DSQLITE_ENABLE_HIDDEN_COLUMNS
    -DSQLITE_MAX_ATTACHED=125
  }
  "Fast-One" {
    -O6
    -DSQLITE_ENABLE_FTS4=1
    -DSQLITE_ENABLE_RTREE=1
    -DSQLITE_ENABLE_STAT4
................................................................................
    -DSQLITE_ENABLE_ATOMIC_WRITE=1
    -DSQLITE_ENABLE_IOTRACE=1
    -DSQLITE_ENABLE_MEMORY_MANAGEMENT=1
    -DSQLITE_MAX_PAGE_SIZE=4096
    -DSQLITE_OMIT_LOAD_EXTENSION=1
    -DSQLITE_OMIT_PROGRESS_CALLBACK=1
    -DSQLITE_OMIT_VIRTUALTABLE=1
    -DSQLITE_ENABLE_HIDDEN_COLUMNS
    -DSQLITE_TEMP_STORE=3
    --enable-json1
  }
  "Device-Two" {
    -DSQLITE_4_BYTE_ALIGNED_MALLOC=1
    -DSQLITE_DEFAULT_AUTOVACUUM=1
    -DSQLITE_DEFAULT_CACHE_SIZE=1000
................................................................................
    -DSQLITE_OMIT_LOOKASIDE=1
    -DHAVE_USLEEP=1
  }
  "Valgrind" {
    -DSQLITE_ENABLE_STAT4
    -DSQLITE_ENABLE_FTS4
    -DSQLITE_ENABLE_RTREE
    -DSQLITE_ENABLE_HIDDEN_COLUMNS
    --enable-json1
  }

  # The next group of configurations are used only by the
  # Failure-Detection platform.  They are all the same, but we need
  # different names for them all so that they results appear in separate
  # subdirectories.