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Add support for the full SQL join syntax. This is just a parser enhancement.

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We now recognize all kinds of joins, but we don't actually do anything with
them yet. (CVS 586)

FossilOrigin-Name: e238643efdbe1394c7ff85e34e486f7c6082b6cc
This commit is contained in:
drh
2002-05-24 16:14:15 +00:00
parent 2e392e2c53
commit 01f3f25376
8 changed files with 157 additions and 38 deletions
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66
src/select.c
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@@ -12,7 +12,7 @@
** This file contains C code routines that are called by the parser
** to handle SELECT statements in SQLite.
**
** $Id: select.c,v 1.82 2002/05/24 02:04:33 drh Exp $
** $Id: select.c,v 1.83 2002/05/24 16:14:15 drh Exp $
*/
#include "sqliteInt.h"
@@ -55,6 +55,70 @@ Select *sqliteSelectNew(
return pNew;
}
/*
** Given 1 to 3 identifiers preceeding the JOIN keyword, determine the
** type of join. Return an integer constant that expresses that type
** in terms of the following bit values:
**
** JT_INNER
** JT_OUTER
** JT_NATURAL
** JT_LEFT
** JT_RIGHT
**
** A full outer join is the combination of JT_LEFT and JT_RIGHT.
**
** If an illegal or unsupported join type is seen, then still return
** a join type, but put an error in the pParse structure.
*/
int sqliteJoinType(Parse *pParse, Token *pA, Token *pB, Token *pC){
int jointype = 0;
Token *apAll[3];
Token *p;
static struct {
const char *zKeyword;
int nChar;
int code;
} keywords[] = {
{ "natural", 7, JT_NATURAL },
{ "left", 4, JT_LEFT },
{ "right", 5, JT_RIGHT },
{ "full", 4, JT_FULL },
{ "outer", 5, JT_OUTER },
{ "inner", 5, JT_INNER },
{ "cross", 5, JT_INNER },
};
int i, j;
apAll[0] = pA;
apAll[1] = pB;
apAll[2] = pC;
for(i=0; apAll[i]; i++){
p = apAll[i];
for(j=0; j<sizeof(keywords)/sizeof(keywords[0]); j++){
if( p->n==keywords[j].nChar
&& sqliteStrNICmp(p->z, keywords[j].zKeyword, p->n)==0 ){
jointype |= keywords[j].code;
break;
}
}
if( j>=sizeof(keywords)/sizeof(keywords[0]) ){
jointype |= JT_ERROR;
break;
}
}
if( (jointype & ~JT_INNER)!=0 ){
static Token dummy = { 0, 0 };
char *zSp1 = " ", *zSp2 = " ";
if( pB==0 ){ pB = &dummy; zSp1 = 0; }
if( pC==0 ){ pC = &dummy; zSp2 = 0; }
sqliteSetNString(&pParse->zErrMsg, "unknown or unsupported join type: ", 0,
pA->z, pA->n, zSp1, 1, pB->z, pB->n, zSp2, 1, pC->z, pC->n, 0);
pParse->nErr++;
jointype = JT_INNER;
}
return jointype;
}
/*
** Delete the given Select structure and all of its substructures.
*/