SQLite

  */
  pInfo->idxNum = FTS3_FULLSCAN_SEARCH;
  pInfo->estimatedCost = 500000;
  for(i=0; i<pInfo->nConstraint; i++){
    struct sqlite3_index_constraint *pCons = &pInfo->aConstraint[i];
    if( pCons->usable==0 ) continue;

    /* A direct lookup on the rowid or docid column. Assign a cost of 1.0. */


    if( pCons->op==SQLITE_INDEX_CONSTRAINT_EQ 
     && (pCons->iColumn<0 || pCons->iColumn==p->nColumn+1 )
    ){
      pInfo->idxNum = FTS3_DOCID_SEARCH;
      pInfo->estimatedCost = 1.0;
      iCons = i;

    }

    /* A MATCH constraint. Use a full-text search.
    **
    ** If there is more than one MATCH constraint available, use the first
    ** one encountered. If there is both a MATCH constraint and a direct
    ** rowid/docid lookup, prefer the MATCH strategy. This is done even 
    ** though the rowid/docid lookup is faster than a MATCH query, selecting
    ** it would lead to an "unable to use function MATCH in the requested 
    ** context" error.
    */

    if( pCons->op==SQLITE_INDEX_CONSTRAINT_MATCH 
     && pCons->iColumn>=0 && pCons->iColumn<=p->nColumn
    ){
      pInfo->idxNum = FTS3_FULLTEXT_SEARCH + pCons->iColumn;
      pInfo->estimatedCost = 2.0;
      iCons = i;
      break;
    }
  }

  if( iCons>=0 ){
    pInfo->aConstraintUsage[iCons].argvIndex = 1;
    pInfo->aConstraintUsage[iCons].omit = 1;
  } 

  uplevel [list do_select_test e_fts3-$tn $sql $result]
}
proc error_test {tn sql result} {
  uplevel [list do_error_test e_fts3-$tn $sql $result]
}




#-------------------------------------------------------------------------
# The body of the following [foreach] block contains test cases to verify
# that the example code in fts3.html works as expected. The tests run three
# times, with different values for DO_MALLOC_TEST.
# 
#   DO_MALLOC_TEST=0: Run tests with no OOM errors.
#   DO_MALLOC_TEST=1: Run tests with transient OOM errors.

write_test 6.4 t5_content { INSERT INTO t6 VALUES('c'); }
read_test  6.5 { SELECT * FROM t6 WHERE t6 MATCH '' } {}
read_test  6.6 { SELECT * FROM t6 WHERE x MATCH '' } {}
read_test  6.7 { SELECT * FROM t6 WHERE t6 MATCH NULL } {}
read_test  6.8 { SELECT * FROM t6 WHERE x MATCH NULL } {}
#-------------------------------------------------------------------------


#-------------------------------------------------------------------------
# Test a few facets of the FTS3 xFilter() callback implementation:
#
#   1. That the sqlite3_index_constraint.usable flag is respected.
#
#   2. That it is an error to use the "docid" or "rowid" column of
#      an FTS3 table as the LHS of a MATCH operator.
#
#   3. That it is an error to AND together two MATCH expressions in 
#      that refer to a single FTS3 table in a WHERE clause.
#
#
set DO_MALLOC_TEST 0
ddl_test   7.1.1 { CREATE VIRTUAL TABLE t7 USING fts3(a) }
ddl_test   7.1.2 { CREATE VIRTUAL TABLE t8 USING fts3(b) }
write_test 7.1.3 t7_content { INSERT INTO t7(docid, a) VALUES(4,'number four') }
write_test 7.1.4 t7_content { INSERT INTO t7(docid, a) VALUES(5,'number five') }
write_test 7.1.5 t8_content { INSERT INTO t8(docid, b) VALUES(4,'letter D') }
write_test 7.1.6 t8_content { INSERT INTO t8(docid, b) VALUES(5,'letter E') }
read_test  7.1.7 {

} {unable to use function MATCH in the requested context}
error_test 7.3.3 {
  SELECT * FROM t7, t8 WHERE b MATCH 'letter' AND b MATCH 'd'
} {unable to use function MATCH in the requested context}
read_test 7.3.4 {
  SELECT * FROM t7, t8 WHERE a MATCH 'number' AND b MATCH 'letter'
} {{number four} {letter D} {number four} {letter E} {number five} {letter D} {number five} {letter E}}
read_test 7.3.5 {
  SELECT * FROM t7 WHERE a MATCH 'number' AND docid = 4
} {{number four}}

#-------------------------------------------------------------------------
# Test the quoting of FTS3 table column names. Names may be quoted using
# any of "", '', ``` or [].
#
set DO_MALLOC_TEST 0
ddl_test  8.1.1 { CREATE VIRTUAL TABLE t9a USING fts3("c1", [c2]) }