SQLite

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle SELECT statements in SQLite.
**
** $Id: select.c,v 1.85 2002/05/25 00:18:21 drh Exp $
*/
#include "sqliteInt.h"

/*
** Allocate a new Select structure and return a pointer to that
** structure.
*/

  Token *p;
  static struct {
    const char *zKeyword;
    int nChar;
    int code;
  } keywords[] = {
    { "natural", 7, JT_NATURAL },
    { "left",    4, JT_LEFT|JT_OUTER },
    { "right",   5, JT_RIGHT|JT_OUTER },
    { "full",    4, JT_LEFT|JT_RIGHT|JT_OUTER },
    { "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; i<3 && 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|JT_OUTER))==(JT_INNER|JT_OUTER) ||
     (jointype & JT_ERROR)!=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;
  }else if( jointype & JT_RIGHT ){
    sqliteSetString(&pParse->zErrMsg, 
      "RIGHT and FULL OUTER JOINs are not currently supported", 0);
    pParse->nErr++;
    jointype = JT_INNER;
  }
  return jointype;
}

/*
** Return the index of a column in a table.  Return -1 if the column

/*
** 2001 September 15
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.116 2002/05/25 00:18:21 drh Exp $
*/
#include "sqlite.h"
#include "hash.h"
#include "vdbe.h"
#include "parse.h"
#include "btree.h"
#include <stdio.h>

};

/*
** Permitted values of the SrcList.a.jointype field
*/
#define JT_INNER     0x0001    /* Any kind of inner or cross join */
#define JT_NATURAL   0x0002    /* True for a "natural" join */
#define JT_LEFT      0x0004    /* Left outer join */
#define JT_RIGHT     0x0008    /* Right outer join */

#define JT_OUTER     0x0010    /* The "OUTER" keyword is present */
#define JT_ERROR     0x0020    /* unknown or unsupported join type */

/*
** For each nested loop in a WHERE clause implementation, the WhereInfo
** structure contains a single instance of this structure.  This structure
** is intended to be private the the where.c module and should not be

#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.
#
# This file implements tests for joins, including outer joins.
#
# $Id: join.test,v 1.2 2002/05/25 00:18:21 drh Exp $

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

do_test join-1.1 {
  execsql {
    CREATE TABLE t1(a,b,c);

} {1 2 3 2 3 4 3 4 5}

do_test join-1.3 {
  execsql2 {
    SELECT * FROM t1 NATURAL JOIN t2;
  }
} {t1.a 1 t1.b 2 t1.c 3 t2.d 4 t1.a 2 t1.b 3 t1.c 4 t2.d 5}
do_test join-1.3.1 {
  execsql2 {
    SELECT * FROM t2 NATURAL JOIN t1;
  }
} {t2.b 2 t2.c 3 t2.d 4 t1.a 1 t2.b 3 t2.c 4 t2.d 5 t1.a 2}
do_test join-1.4 {
  execsql2 {
    SELECT * FROM t1 INNER JOIN t2 USING(b,c);
  }
} {t1.a 1 t1.b 2 t1.c 3 t2.d 4 t1.a 2 t1.b 3 t1.c 4 t2.d 5}
do_test join-1.5 {
  execsql2 {
    SELECT * FROM t1 INNER JOIN t2 USING(b);
  }
} {t1.a 1 t1.b 2 t1.c 3 t2.c 3 t2.d 4 t1.a 2 t1.b 3 t1.c 4 t2.c 4 t2.d 5}
do_test join-1.6 {
  execsql2 {
    SELECT * FROM t1 INNER JOIN t2 USING(c);
  }
} {t1.a 1 t1.b 2 t1.c 3 t2.b 2 t2.d 4 t1.a 2 t1.b 3 t1.c 4 t2.b 3 t2.d 5}
do_test join-1.7 {
  execsql2 {
    SELECT * FROM t1 INNER JOIN t2 USING(c,b);
  }
} {t1.a 1 t1.b 2 t1.c 3 t2.d 4 t1.a 2 t1.b 3 t1.c 4 t2.d 5}

do_test join-1.8 {
  execsql {
    SELECT * FROM t1 NATURAL CROSS JOIN t2;
  }
} {1 2 3 4 2 3 4 5}
do_test join-1.9 {
  execsql {
    SELECT * FROM t1 CROSS JOIN t2 USING(b,c);
  }
} {1 2 3 4 2 3 4 5}
do_test join-1.10 {
  execsql {
    SELECT * FROM t1 NATURAL INNER JOIN t2;
  }
} {1 2 3 4 2 3 4 5}
do_test join-1.11 {
  execsql {
    SELECT * FROM t1 INNER JOIN t2 USING(b,c);
  }
} {1 2 3 4 2 3 4 5}
do_test join-1.12 {
  execsql {
    SELECT * FROM t1 natural inner join t2;
  }
} {1 2 3 4 2 3 4 5}
do_test join-1.13 {
  execsql2 {
    SELECT * FROM t1 NATURAL JOIN 
      (SELECT b as 'c', c as 'd', d as 'e' FROM t2) as t3
  }
} {t1.a 1 t1.b 2 t1.c 3 t3.d 4 t3.e 5}
do_test join-1.14 {
  execsql2 {
    SELECT * FROM (SELECT b as 'c', c as 'd', d as 'e' FROM t2) as 'tx'
        NATURAL JOIN t1
  }
} {tx.c 3 tx.d 4 tx.e 5 t1.a 1 t1.b 2}

do_test join-1.15 {
  execsql {
    CREATE TABLE t3(c,d,e);
    INSERT INTO t3 VALUES(2,3,4);
    INSERT INTO t3 VALUES(3,4,5);
    INSERT INTO t3 VALUES(4,5,6);
    SELECT * FROM t3;
  }  
} {2 3 4 3 4 5 4 5 6}
do_test join-1.16 {
  execsql {
    SELECT * FROM t1 natural join t2 natural join t3;
  }
} {1 2 3 4 5 2 3 4 5 6}
do_test join-1.17 {
  execsql2 {
    SELECT * FROM t1 natural join t2 natural join t3;
  }
} {t1.a 1 t1.b 2 t1.c 3 t2.d 4 t3.e 5 t1.a 2 t1.b 3 t1.c 4 t2.d 5 t3.e 6}
do_test join-1.18 {
  execsql {
    CREATE TABLE t4(d,e,f);
    INSERT INTO t4 VALUES(2,3,4);
    INSERT INTO t4 VALUES(3,4,5);
    INSERT INTO t4 VALUES(4,5,6);
    SELECT * FROM t4;
  }  
} {2 3 4 3 4 5 4 5 6}
do_test join-1.19 {
  execsql {
    SELECT * FROM t1 natural join t2 natural join t4;
  }
} {1 2 3 4 5 6}
do_test join-1.19 {
  execsql2 {
    SELECT * FROM t1 natural join t2 natural join t4;
  }
} {t1.a 1 t1.b 2 t1.c 3 t2.d 4 t4.e 5 t4.f 6}
do_test join-1.20 {
  execsql {
    SELECT * FROM t1 natural join t2 natural join t3 WHERE t1.a=1
  }
} {1 2 3 4 5}

do_test join-2.1 {
  execsql {
    SELECT * FROM t1 NATURAL LEFT JOIN t2;
  }
} {1 2 3 4 2 3 4 5 3 4 5 {}}
do_test join-2.2 {
  execsql {
    SELECT * FROM t2 NATURAL LEFT OUTER JOIN t1;
  }
} {1 2 3 {} 2 3 4 1 3 4 5 2}
do_test join-2.3 {
  catchsql {
    SELECT * FROM t1 NATURAL RIGHT OUTER JOIN t2;
  }
} {1 {RIGHT and FULL OUTER JOINs are not currently supported}}

do_test join-3.1 {
  catchsql {
    SELECT * FROM t1 NATURAL JOIN t2 ON t1.a=t2.b;
  }
} {1 {a NATURAL join may not have an ON or USING clause}}
do_test join-3.2 {
  catchsql {
    SELECT * FROM t1 NATURAL JOIN t2 USING(b);
  }
} {1 {a NATURAL join may not have an ON or USING clause}}
do_test join-3.3 {
  catchsql {
    SELECT * FROM t1 JOIN t2 ON t1.a=t2.b USING(b);
  }
} {1 {cannot have both ON and USING clauses in the same join}}
do_test join-3.4 {
  catchsql {
    SELECT * FROM t1 JOIN t2 USING(a);
  }
} {1 {cannot join using column a - column not present in both tables}}
do_test join-3.5 {
  catchsql {
    SELECT * FROM t1 USING(a);
  }
} {0 {1 2 3 2 3 4 3 4 5}}
do_test join-3.6 {
  catchsql {
    SELECT * FROM t1 JOIN t2 ON t3.a=t2.b;
  }
} {1 {no such column: t3.a}}
do_test join-3.7 {
  catchsql {
    SELECT * FROM t1 INNER OUTER JOIN t2;
  }
} {1 {unknown or unsupported join type: INNER OUTER}}
do_test join-3.7 {
  catchsql {
    SELECT * FROM t1 BOGUS JOIN t2;
  }
} {1 {unknown or unsupported join type: BOGUS}}


finish_test