SQLite

  if( iLangidCons>=0 ){
    pInfo->aConstraintUsage[iLangidCons].argvIndex = 2;
  } 

  /* Regardless of the strategy selected, FTS can deliver rows in rowid (or
  ** docid) order. Both ascending and descending are possible. 
  */
  assert( pInfo->orderByConsumed==0 );
  if( pInfo->nOrderBy==1 ){
    struct sqlite3_index_orderby *pOrder = &pInfo->aOrderBy[0];
    if( pOrder->iColumn<0 || (
          (pOrder->iColumn==p->nColumn+1)
       && (pInfo->idxNum>=FTS3_FULLTEXT_SEARCH || p->nLanguageidBits==0)
    )){
      if( pOrder->desc ){
        pInfo->idxStr = "DESC";
      }else{
        pInfo->idxStr = "ASC";
      }
      pInfo->orderByConsumed = 1;
    }

  return rc;
}

/*
** Convert a docid (iDocid) and a language id (iLangid) to a rowid,
** according to the configured languageid_bits= value belonging to
** FTS table *p.
**
** The conversion is as follows:
**
**   * The sign bit of iDocid becomes the sign bit of the rowid.
**
**   * iLangid is converted to an unsigned integer and stored in
**     the next most significant Fts3Table.nLanguageidBits bits
**     of the returned rowid.
**
**   * The least signficant (63-nLanguageidBits) of iDocid are
**     copied to the (63-nLanguageidBits) least signifcant bits of
**     the returned rowid.
*/
i64 sqlite3Fts3DocidToRowid(Fts3Table *p, i64 iDocid, int iLangid){
  u64 iRet = iDocid;

  if( p->nLanguageidBits ){
    int iShift = (63 - p->nLanguageidBits);
    u64 mask = ((((u64)1 << p->nLanguageidBits) - 1) << iShift);

    iRet &= ~mask;
    iRet |= (u64)iLangid << iShift;
  }

  assert( sqlite3Fts3RowidToDocid(p, (i64)iRet)==iDocid );
  return (i64)iRet;
}

/*
** Convert a rowid (iRowid) to a docid according to the languageid_bits=
** value belonging to FTS table *p.
*/
i64 sqlite3Fts3RowidToDocid(Fts3Table *p, i64 iRowid){
  u64 iRet = iRowid;
  if( p->nLanguageidBits ){
    static const u64 signbit = ((u64)1 << 63);
    u64 mask = ((((u64)1 << p->nLanguageidBits)-1) << (63-p->nLanguageidBits));

    if( iRet & signbit ){
      iRet |= mask;
    }else{
      iRet &= ~mask;
    }
  }
  return (i64)iRet;
}

/*
** This function does the work for the xUpdate method of FTS3 virtual
** tables. The schema of the virtual table being:
**
**     CREATE TABLE <table name>( 

# If SQLITE_ENABLE_FTS3 is defined, omit this file.
ifcapable !fts3 {
  finish_test
  return
}


#-------------------------------------------------------------------------
# Test out-of-range values for the languageid_bits= parameter.
#
do_catchsql_test 1.1 {
  CREATE VIRTUAL TABLE t1 USING fts4(languageid=lid, languageid_bits=31);
} {1 {languageid_bits parameter out of range}}

  SELECT docid, mit(matchinfo(t1)) FROM t1 WHERE t1 MATCH 'B' AND lid=1;
} {}
do_execsql_test 6.3.4 {
  SELECT docid, mit(matchinfo(t1)) FROM t1 WHERE t1 MATCH 'B' AND lid=2;
} {4 {1 1 1 1 1}}

do_execsql_test 6.4 {
  CREATE VIRTUAL TABLE t2 USING fts4(languageid_bits=8, languageid=lid);
  INSERT INTO t2(docid,lid,content) VALUES(-1, 0, 'A B C D');
  INSERT INTO t2(docid,lid,content) VALUES(-2, 0, 'D C B A');
  INSERT INTO t2(docid,lid,content) VALUES(-3, 0, 'C B D A');
  INSERT INTO t2(docid,lid,content) VALUES(-4, 0, 'A D B C');

  INSERT INTO t2(docid,lid,content) VALUES(-1, 1, 'A A A A');
  INSERT INTO t2(docid,lid,content) VALUES(-2, 1, 'B B B B');
  INSERT INTO t2(docid,lid,content) VALUES(-3, 1, 'C C C C');
  INSERT INTO t2(docid,lid,content) VALUES(-4, 1, 'D D D D');
}

do_execsql_test 6.4.1 {
  SELECT docid, mit(matchinfo(t2)) FROM t2 WHERE t2 MATCH 'B';
} {
  -4 {1 1 1 4 4}
  -3 {1 1 1 4 4}
  -2 {1 1 1 4 4}
  -1 {1 1 1 4 4}
}
do_execsql_test 6.4.2 {
  SELECT docid, mit(matchinfo(t2)) FROM t2 WHERE t2 MATCH 'B' AND lid=1;
} {-2 {1 1 4 4 1}}

do_execsql_test 6.5 {
  DROP TABLE t1;
  DROP TABLE t2;
}

#-------------------------------------------------------------------------
# Tests for querying by docid.
#

do_execsql_test 7.1 {
  CREATE VIRTUAL TABLE t1 USING fts4(languageid_bits=8, languageid=lid);
  INSERT INTO t1(docid,lid,content) VALUES(10, 10, 'abc def');
}

do_execsql_test 7.2 {
  SELECT docid,lid,content FROM t1 WHERE docid=10;
} {10 10 {abc def}}

do_execsql_test 7.3 {
  SELECT docid,lid,content FROM t1 WHERE docid<11;
} {10 10 {abc def}}

do_execsql_test 7.4 {
  DROP TABLE t1;
}

#-------------------------------------------------------------------------
# Tests for sorting by docid.
#
do_execsql_test 8.1 {
  CREATE VIRTUAL TABLE t1 USING fts4(languageid_bits=6, languageid=lid);
  INSERT INTO t1 (docid,lid,content) VALUES(1, 0, 'abc def');
  INSERT INTO t1 (docid,lid,content) VALUES(3, 0, 'abc ghi');
  INSERT INTO t1 (docid,lid,content) VALUES(2, 0, 'def ghi');

  INSERT INTO t1 (docid,lid,content) VALUES(1, 5, 'A B');
  INSERT INTO t1 (docid,lid,content) VALUES(3, 5, 'A C');
  INSERT INTO t1 (docid,lid,content) VALUES(2, 5, 'B C');
}

do_execsql_test 8.2 {
  SELECT docid FROM t1 ORDER BY docid;
} {1 1 2 2 3 3}

do_execsql_test 8.2 {
  SELECT docid FROM t1 WHERE t1 MATCH 'ghi' ORDER BY docid;
} {2 3}

do_execsql_test 8.2 {
  SELECT docid FROM t1 WHERE t1 MATCH 'ghi' ORDER BY docid DESC;
} {3 2}

finish_test