-C Fix\sa\sproblem\sin\san\slsmtest\stest\scase\scaused\sby\swriting\sdata\sin\s"text"\smode\ninstead\sof\s"binary".
-D 2017-07-12T14:03:13.542
+C Clarification\sand\ssimplification\sand\sresult\scolumn\snaming\slogic.
+D 2017-07-12T14:10:19.869
F Makefile.in 081e48dfe7f995d57ce1a88ddf4d2917b4349158648a6cd45b42beae30de3a12
F Makefile.linux-gcc 7bc79876b875010e8c8f9502eb935ca92aa3c434
F Makefile.msc 20850e3e8d4d4791e0531955852d768eb06f24138214870d543abb1a47346fba
F src/random.c 80f5d666f23feb3e6665a6ce04c7197212a88384
F src/resolve.c 6aa1fb1212e601f65b983ee1215d69a591986c8f97a3805c425c625a53839539
F src/rowset.c 7b7e7e479212e65b723bf40128c7b36dc5afdfac
-F src/select.c 6aa7e8ee53dcb9d0b77b05670bb44a1076d6747bc9b2c1f12a365b553ab6c828
+F src/select.c 95659b7990e390f9bd8dc30b8975c675fcd1d46e569bc4f5a14e22a8d03e3d14
F src/shell.c 0401a716fc5343594b8ee60ce065d9a71373d3403f0b81f9fed684741e6401d1
F src/shell.c.in 98bfdeeb0808418b37f59e6d380568a76e0733efe2494377096f434b39940cad
F src/sqlite.h.in 03a422ba13da1dfef7f1aaa1ba344acf18dc867112620b1fdb2a1426cabba634
F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 783100b801703577e35ec12fe7623e1797e49699f3b8deb0694ef061a142b844
-R ab6ba7417c8ef7732b2a8b211358e460
-U dan
-Z df42a5b7a8146f5aa8e5ac6a01bf086c
+P 3e56a79ad8754e6da3181883154fa1c8b227a8d16c9b2a3eba925371595ae1f9
+R 262c8bdac1ac6c4d0dad5be8958ad15e
+U drh
+Z 4894df80f0f6930b7360c2bd22600907
/*
-** Generate code that will tell the VDBE the names of columns
-** in the result set. This information is used to provide the
-** azCol[] values in the callback.
+** Compute the column names for a SELECT statement.
+**
+** The only guarantee that SQLite makes about column names is that if the
+** column has an AS clause assigning it a name, that will be the name used.
+** That is the only documented guarantee. However, countless applications
+** developed over the years have made baseless assumptions about column names
+** and will break if those assumptions changes. Hence, use extreme caution
+** when modifying this routine to avoid breaking legacy.
+**
+** See Also: sqlite3ColumnsFromExprList()
+**
+** The PRAGMA short_column_names and PRAGMA full_column_names settings are
+** deprecated. The default setting is short=ON, full=OFF. 99.9% of all
+** applications should operate this way. Nevertheless, we need to support the
+** other modes for legacy:
+**
+** short=OFF, full=OFF: Column name is the text of the expression has it
+** originally appears in the SELECT statement. In
+** other words, the zSpan of the result expression.
+**
+** short=ON, full=OFF: (This is the default setting). If the result
+** refers directly to a table column, then the result
+** column name is just the table column name: COLUMN.
+** Otherwise use zSpan.
+**
+** full=ON, short=ANY: If the result refers directly to a table column,
+** then the result column name with the table name
+** prefix, ex: TABLE.COLUMN. Otherwise use zSpan.
*/
static void generateColumnNames(
Parse *pParse, /* Parser context */
- SrcList *pTabList, /* List of tables */
+ SrcList *pTabList, /* The FROM clause of the SELECT */
ExprList *pEList /* Expressions defining the result set */
){
Vdbe *v = pParse->pVdbe;
int i;
Table *pTab;
sqlite3 *db = pParse->db;
- int fullNames, shortNames;
+ int fullName; /* TABLE.COLUMN if no AS clause and is a direct table ref */
+ int srcName; /* COLUMN or TABLE.COLUMN if no AS clause and is direct */
#ifndef SQLITE_OMIT_EXPLAIN
/* If this is an EXPLAIN, skip this step */
assert( v!=0 );
assert( pTabList!=0 );
pParse->colNamesSet = 1;
- fullNames = (db->flags & SQLITE_FullColNames)!=0;
- shortNames = (db->flags & SQLITE_ShortColNames)!=0;
+ fullName = (db->flags & SQLITE_FullColNames)!=0;
+ srcName = (db->flags & SQLITE_ShortColNames)!=0 || fullName;
sqlite3VdbeSetNumCols(v, pEList->nExpr);
for(i=0; i<pEList->nExpr; i++){
- Expr *p;
- p = pEList->a[i].pExpr;
- if( NEVER(p==0) ) continue;
+ Expr *p = pEList->a[i].pExpr;
+
+ assert( p!=0 );
if( pEList->a[i].zName ){
+ /* An AS clause always takes first priority */
char *zName = pEList->a[i].zName;
sqlite3VdbeSetColName(v, i, COLNAME_NAME, zName, SQLITE_TRANSIENT);
- }else if( (p->op==TK_COLUMN || p->op==TK_AGG_COLUMN)
+ }else if( srcName
+ && (p->op==TK_COLUMN || p->op==TK_AGG_COLUMN)
&& (pTab = tableWithCursor(pTabList, p->iTable))!=0
){
char *zCol;
}else{
zCol = pTab->aCol[iCol].zName;
}
- if( !shortNames && !fullNames ){
- sqlite3VdbeSetColName(v, i, COLNAME_NAME,
- sqlite3DbStrDup(db, pEList->a[i].zSpan), SQLITE_DYNAMIC);
- }else if( fullNames ){
+ if( fullName ){
char *zName = 0;
zName = sqlite3MPrintf(db, "%s.%s", pTab->zName, zCol);
sqlite3VdbeSetColName(v, i, COLNAME_NAME, zName, SQLITE_DYNAMIC);
**
** Return SQLITE_OK on success. If a memory allocation error occurs,
** store NULL in *paCol and 0 in *pnCol and return SQLITE_NOMEM.
+**
+** The only guarantee that SQLite makes about column names is that if the
+** column has an AS clause assigning it a name, that will be the name used.
+** That is the only documented guarantee. However, countless applications
+** developed over the years have made baseless assumptions about column names
+** and will break if those assumptions changes. Hence, use extreme caution
+** when modifying this routine to avoid breaking legacy.
+**
+** See Also: generateColumnNames()
*/
int sqlite3ColumnsFromExprList(
Parse *pParse, /* Parsing context */
u32 cnt; /* Index added to make the name unique */
Column *aCol, *pCol; /* For looping over result columns */
int nCol; /* Number of columns in the result set */
- Expr *p; /* Expression for a single result column */
char *zName; /* Column name */
int nName; /* Size of name in zName[] */
Hash ht; /* Hash table of column names */
for(i=0, pCol=aCol; i<nCol && !db->mallocFailed; i++, pCol++){
/* Get an appropriate name for the column
*/
- p = sqlite3ExprSkipCollate(pEList->a[i].pExpr);
if( (zName = pEList->a[i].zName)!=0 ){
/* If the column contains an "AS <name>" phrase, use <name> as the name */
}else{
- Expr *pColExpr = p; /* The expression that is the result column name */
- Table *pTab; /* Table associated with this expression */
+ Expr *pColExpr = sqlite3ExprSkipCollate(pEList->a[i].pExpr);
while( pColExpr->op==TK_DOT ){
pColExpr = pColExpr->pRight;
assert( pColExpr!=0 );
if( pColExpr->op==TK_COLUMN && pColExpr->pTab!=0 ){
/* For columns use the column name name */
int iCol = pColExpr->iColumn;
- pTab = pColExpr->pTab;
+ Table *pTab = pColExpr->pTab;
if( iCol<0 ) iCol = pTab->iPKey;
zName = iCol>=0 ? pTab->aCol[iCol].zName : "rowid";
}else if( pColExpr->op==TK_ID ){
projects / thirdparty / sqlite.git / commitdiff
