[sql] Import SQLite 3.17.0.

third_party/sqlite/src/ext/fts3/fts3_write.c

 /*
 ** 2009 Oct 23
 **
 ** 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.
 **
@@ skipping 315 matching lines @@
 /* 25 */  "",
 
 /* 26 */ "DELETE FROM %Q.'%q_segdir' WHERE level BETWEEN ? AND ?",
 /* 27 */ "SELECT ? UNION SELECT level / (1024 * ?) FROM %Q.'%q_segdir'",
 
 /* This statement is used to determine which level to read the input from
 ** when performing an incremental merge. It returns the absolute level number
 ** of the oldest level in the db that contains at least ? segments. Or,
 ** if no level in the FTS index contains more than ? segments, the statement
 ** returns zero rows.  */
-/* 28 */ "SELECT level FROM %Q.'%q_segdir' GROUP BY level HAVING count(*)>=?"
+/* 28 */ "SELECT level, count(*) AS cnt FROM %Q.'%q_segdir' "
+         "  GROUP BY level HAVING cnt>=?"
          "  ORDER BY (level %% 1024) ASC LIMIT 1",
 
 /* Estimate the upper limit on the number of leaf nodes in a new segment
 ** created by merging the oldest :2 segments from absolute level :1. See 
 ** function sqlite3Fts3Incrmerge() for details.  */
 /* 29 */ "SELECT 2 * total(1 + leaves_end_block - start_block) "
          "  FROM %Q.'%q_segdir' WHERE level = ? AND idx < ?",
 
 /* SQL_DELETE_SEGDIR_ENTRY
 **   Delete the %_segdir entry on absolute level :1 with index :2.  */
@@ skipping 2840 matching lines @@
   if( iLevel!=FTS3_SEGCURSOR_PENDING ){
     rc = fts3SegmentMaxLevel(p, iLangid, iIndex, &iMaxLevel);
     if( rc!=SQLITE_OK ) goto finished;
   }
 
   if( iLevel==FTS3_SEGCURSOR_ALL ){
     /* This call is to merge all segments in the database to a single
     ** segment. The level of the new segment is equal to the numerically
     ** greatest segment level currently present in the database for this
     ** index. The idx of the new segment is always 0.  */
-    if( csr.nSegment==1 ){
+    if( csr.nSegment==1 && 0==fts3SegReaderIsPending(csr.apSegment[0]) ){
       rc = SQLITE_DONE;
       goto finished;
     }
     iNewLevel = iMaxLevel;
     bIgnoreEmpty = 1;
 
   }else{
     /* This call is to merge all segments at level iLevel. find the next
     ** available segment index at level iLevel+1. The call to
     ** fts3AllocateSegdirIdx() will merge the segments at level iLevel+1 to 
@@ skipping 1621 matching lines @@
     int bUseHint = 0;             /* True if attempting to append */
     int iIdx = 0;                 /* Largest idx in level (iAbsLevel+1) */
 
     /* Search the %_segdir table for the absolute level with the smallest
     ** relative level number that contains at least nMin segments, if any.
     ** If one is found, set iAbsLevel to the absolute level number and
     ** nSeg to nMin. If no level with at least nMin segments can be found, 
     ** set nSeg to -1.
     */
     rc = fts3SqlStmt(p, SQL_FIND_MERGE_LEVEL, &pFindLevel, 0);
-    sqlite3_bind_int(pFindLevel, 1, nMin);
+    sqlite3_bind_int(pFindLevel, 1, MAX(2, nMin));
     if( sqlite3_step(pFindLevel)==SQLITE_ROW ){
       iAbsLevel = sqlite3_column_int64(pFindLevel, 0);
-      nSeg = nMin;
+      nSeg = sqlite3_column_int(pFindLevel, 1);
+      assert( nSeg>=2 );
     }else{
       nSeg = -1;
     }
     rc = sqlite3_reset(pFindLevel);
 
     /* If the hint read from the %_stat table is not empty, check if the
     ** last entry in it specifies a relative level smaller than or equal
     ** to the level identified by the block above (if any). If so, this 
     ** iteration of the loop will work on merging at the hinted level.
     */
@@ skipping 814 matching lines @@
     }else{
       sqlite3_exec(p->db, "ROLLBACK TO fts3", 0, 0, 0);
       sqlite3_exec(p->db, "RELEASE fts3", 0, 0, 0);
     }
   }
   sqlite3Fts3SegmentsClose(p);
   return rc;
 }
 
 #endif