/ Check-in [d6b66cd7]
Login

Many hyperlinks are disabled.
Use anonymous login to enable hyperlinks.

Overview
Comment:Update fts3 so that expressions to the left and right of a NOT operator are balanced. This prevents relatively small expressions (a dozen terms or so) that are children of NOT operators from triggering the "expression tree is too large" error.
Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA1:d6b66cd7b89fbd964f798d160a34caac0ba7347a
User & Date: dan 2015-10-05 15:39:45
Context
2015-10-05
19:41
Improve performance of prefix queries without a prefix index on fts5 tables. check-in: f2f0184e user: dan tags: trunk
15:39
Update fts3 so that expressions to the left and right of a NOT operator are balanced. This prevents relatively small expressions (a dozen terms or so) that are children of NOT operators from triggering the "expression tree is too large" error. check-in: d6b66cd7 user: dan tags: trunk
11:57
Add fts5txt2db.tcl, a tool for creating sample fts4/5 databases from text files. check-in: 44f1ce30 user: dan tags: trunk
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to ext/fts3/fts3_expr.c.

789
790
791
792
793
794
795

796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912



913




914


















915
916
917
918
919
920
921
  Fts3Expr *pFree = 0;            /* List of free nodes. Linked by pParent. */
  int eType = pRoot->eType;       /* Type of node in this tree */

  if( nMaxDepth==0 ){
    rc = SQLITE_ERROR;
  }


  if( rc==SQLITE_OK && (eType==FTSQUERY_AND || eType==FTSQUERY_OR) ){
    Fts3Expr **apLeaf;
    apLeaf = (Fts3Expr **)sqlite3_malloc(sizeof(Fts3Expr *) * nMaxDepth);
    if( 0==apLeaf ){
      rc = SQLITE_NOMEM;
    }else{
      memset(apLeaf, 0, sizeof(Fts3Expr *) * nMaxDepth);
    }

    if( rc==SQLITE_OK ){
      int i;
      Fts3Expr *p;

      /* Set $p to point to the left-most leaf in the tree of eType nodes. */
      for(p=pRoot; p->eType==eType; p=p->pLeft){
        assert( p->pParent==0 || p->pParent->pLeft==p );
        assert( p->pLeft && p->pRight );
      }

      /* This loop runs once for each leaf in the tree of eType nodes. */
      while( 1 ){
        int iLvl;
        Fts3Expr *pParent = p->pParent;     /* Current parent of p */

        assert( pParent==0 || pParent->pLeft==p );
        p->pParent = 0;
        if( pParent ){
          pParent->pLeft = 0;
        }else{
          pRoot = 0;
        }
        rc = fts3ExprBalance(&p, nMaxDepth-1);
        if( rc!=SQLITE_OK ) break;

        for(iLvl=0; p && iLvl<nMaxDepth; iLvl++){
          if( apLeaf[iLvl]==0 ){
            apLeaf[iLvl] = p;
            p = 0;
          }else{
            assert( pFree );
            pFree->pLeft = apLeaf[iLvl];
            pFree->pRight = p;
            pFree->pLeft->pParent = pFree;
            pFree->pRight->pParent = pFree;

            p = pFree;
            pFree = pFree->pParent;
            p->pParent = 0;
            apLeaf[iLvl] = 0;
          }
        }
        if( p ){
          sqlite3Fts3ExprFree(p);
          rc = SQLITE_TOOBIG;
          break;
        }

        /* If that was the last leaf node, break out of the loop */
        if( pParent==0 ) break;

        /* Set $p to point to the next leaf in the tree of eType nodes */
        for(p=pParent->pRight; p->eType==eType; p=p->pLeft);

        /* Remove pParent from the original tree. */
        assert( pParent->pParent==0 || pParent->pParent->pLeft==pParent );
        pParent->pRight->pParent = pParent->pParent;
        if( pParent->pParent ){
          pParent->pParent->pLeft = pParent->pRight;
        }else{
          assert( pParent==pRoot );
          pRoot = pParent->pRight;
        }

        /* Link pParent into the free node list. It will be used as an
        ** internal node of the new tree.  */
        pParent->pParent = pFree;
        pFree = pParent;
      }

      if( rc==SQLITE_OK ){
        p = 0;
        for(i=0; i<nMaxDepth; i++){
          if( apLeaf[i] ){
            if( p==0 ){
              p = apLeaf[i];
              p->pParent = 0;
            }else{
              assert( pFree!=0 );
              pFree->pRight = p;
              pFree->pLeft = apLeaf[i];
              pFree->pLeft->pParent = pFree;
              pFree->pRight->pParent = pFree;

              p = pFree;
              pFree = pFree->pParent;
              p->pParent = 0;
            }
          }
        }
        pRoot = p;
      }else{
        /* An error occurred. Delete the contents of the apLeaf[] array 
        ** and pFree list. Everything else is cleaned up by the call to
        ** sqlite3Fts3ExprFree(pRoot) below.  */
        Fts3Expr *pDel;
        for(i=0; i<nMaxDepth; i++){
          sqlite3Fts3ExprFree(apLeaf[i]);
        }
        while( (pDel=pFree)!=0 ){
          pFree = pDel->pParent;
          sqlite3_free(pDel);
        }
      }

      assert( pFree==0 );
      sqlite3_free( apLeaf );
    }



  }























  if( rc!=SQLITE_OK ){
    sqlite3Fts3ExprFree(pRoot);
    pRoot = 0;
  }
  *pp = pRoot;
  return rc;
}







>
|
|
|
|
|
|
|
|

|
|
|

|
|
|
|
|

|
|
|
|

|
|
|
|
|
|
|
|
|

|
|
|
|
|
|
|
|
|
|

|
|
|
|
|
|
|
|
|
|
|

|
|

|
|

|
|
|
|
|
|
|
|
|

|
|
|
|
|

|
|
|
|
|
|
|
|
|
|
|
|
|

|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|

|
|
|
>
>
>
|
>
>
>
>

>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>







789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
  Fts3Expr *pFree = 0;            /* List of free nodes. Linked by pParent. */
  int eType = pRoot->eType;       /* Type of node in this tree */

  if( nMaxDepth==0 ){
    rc = SQLITE_ERROR;
  }

  if( rc==SQLITE_OK ){
    if( (eType==FTSQUERY_AND || eType==FTSQUERY_OR) ){
      Fts3Expr **apLeaf;
      apLeaf = (Fts3Expr **)sqlite3_malloc(sizeof(Fts3Expr *) * nMaxDepth);
      if( 0==apLeaf ){
        rc = SQLITE_NOMEM;
      }else{
        memset(apLeaf, 0, sizeof(Fts3Expr *) * nMaxDepth);
      }

      if( rc==SQLITE_OK ){
        int i;
        Fts3Expr *p;

        /* Set $p to point to the left-most leaf in the tree of eType nodes. */
        for(p=pRoot; p->eType==eType; p=p->pLeft){
          assert( p->pParent==0 || p->pParent->pLeft==p );
          assert( p->pLeft && p->pRight );
        }

        /* This loop runs once for each leaf in the tree of eType nodes. */
        while( 1 ){
          int iLvl;
          Fts3Expr *pParent = p->pParent;     /* Current parent of p */

          assert( pParent==0 || pParent->pLeft==p );
          p->pParent = 0;
          if( pParent ){
            pParent->pLeft = 0;
          }else{
            pRoot = 0;
          }
          rc = fts3ExprBalance(&p, nMaxDepth-1);
          if( rc!=SQLITE_OK ) break;

          for(iLvl=0; p && iLvl<nMaxDepth; iLvl++){
            if( apLeaf[iLvl]==0 ){
              apLeaf[iLvl] = p;
              p = 0;
            }else{
              assert( pFree );
              pFree->pLeft = apLeaf[iLvl];
              pFree->pRight = p;
              pFree->pLeft->pParent = pFree;
              pFree->pRight->pParent = pFree;

              p = pFree;
              pFree = pFree->pParent;
              p->pParent = 0;
              apLeaf[iLvl] = 0;
            }
          }
          if( p ){
            sqlite3Fts3ExprFree(p);
            rc = SQLITE_TOOBIG;
            break;
          }

          /* If that was the last leaf node, break out of the loop */
          if( pParent==0 ) break;

          /* Set $p to point to the next leaf in the tree of eType nodes */
          for(p=pParent->pRight; p->eType==eType; p=p->pLeft);

          /* Remove pParent from the original tree. */
          assert( pParent->pParent==0 || pParent->pParent->pLeft==pParent );
          pParent->pRight->pParent = pParent->pParent;
          if( pParent->pParent ){
            pParent->pParent->pLeft = pParent->pRight;
          }else{
            assert( pParent==pRoot );
            pRoot = pParent->pRight;
          }

          /* Link pParent into the free node list. It will be used as an
          ** internal node of the new tree.  */
          pParent->pParent = pFree;
          pFree = pParent;
        }

        if( rc==SQLITE_OK ){
          p = 0;
          for(i=0; i<nMaxDepth; i++){
            if( apLeaf[i] ){
              if( p==0 ){
                p = apLeaf[i];
                p->pParent = 0;
              }else{
                assert( pFree!=0 );
                pFree->pRight = p;
                pFree->pLeft = apLeaf[i];
                pFree->pLeft->pParent = pFree;
                pFree->pRight->pParent = pFree;

                p = pFree;
                pFree = pFree->pParent;
                p->pParent = 0;
              }
            }
          }
          pRoot = p;
        }else{
          /* An error occurred. Delete the contents of the apLeaf[] array 
          ** and pFree list. Everything else is cleaned up by the call to
          ** sqlite3Fts3ExprFree(pRoot) below.  */
          Fts3Expr *pDel;
          for(i=0; i<nMaxDepth; i++){
            sqlite3Fts3ExprFree(apLeaf[i]);
          }
          while( (pDel=pFree)!=0 ){
            pFree = pDel->pParent;
            sqlite3_free(pDel);
          }
        }

        assert( pFree==0 );
        sqlite3_free( apLeaf );
      }
    }else if( eType==FTSQUERY_NOT ){
      Fts3Expr *pLeft = pRoot->pLeft;
      Fts3Expr *pRight = pRoot->pRight;

      pRoot->pLeft = 0;
      pRoot->pRight = 0;
      pLeft->pParent = 0;
      pRight->pParent = 0;

      rc = fts3ExprBalance(&pLeft, nMaxDepth-1);
      if( rc==SQLITE_OK ){
        rc = fts3ExprBalance(&pRight, nMaxDepth-1);
      }

      if( rc!=SQLITE_OK ){
        sqlite3Fts3ExprFree(pRight);
        sqlite3Fts3ExprFree(pLeft);
      }else{
        assert( pLeft && pRight );
        pRoot->pLeft = pLeft;
        pLeft->pParent = pRoot;
        pRoot->pRight = pRight;
        pRight->pParent = pRoot;
      }
    }
  }
  
  if( rc!=SQLITE_OK ){
    sqlite3Fts3ExprFree(pRoot);
    pRoot = 0;
  }
  *pp = pRoot;
  return rc;
}

Changes to test/fts3expr3.test.

117
118
119
120
121
122
123


124
125
126
127
128
129
130
...
197
198
199
200
201
202
203
204






























205
206
proc balanced_andor_tree {nEntry} {
  set tree [balanced_exprtree_structure $nEntry]
  set node "{[balanced_and_tree $nEntry]}"
  regsub -all AND $node OR node
  regsub -all xxx $tree $node tree
  return $tree
}



# Test that queries like "1 AND 2 AND 3 AND 4..." are transformed to 
# balanced trees by FTS.
#
for {set i 1} {$i < 100} {incr i} {
  do_test 1.$i {
    test_fts3expr2 [random_and_query $i]
................................................................................
set query [random_andor_query 12]
set result [balanced_andor_tree 12]
do_faultsim_test fts3expr3-fault-1 -faults oom-* -body {
  test_fts3expr2 $::query
} -test {
  faultsim_test_result [list 0 $::result]
}































set sqlite_fts3_enable_parentheses 0
finish_test







>
>







 








>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>


117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
...
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
proc balanced_andor_tree {nEntry} {
  set tree [balanced_exprtree_structure $nEntry]
  set node "{[balanced_and_tree $nEntry]}"
  regsub -all AND $node OR node
  regsub -all xxx $tree $node tree
  return $tree
}

if 1 {

# Test that queries like "1 AND 2 AND 3 AND 4..." are transformed to 
# balanced trees by FTS.
#
for {set i 1} {$i < 100} {incr i} {
  do_test 1.$i {
    test_fts3expr2 [random_and_query $i]
................................................................................
set query [random_andor_query 12]
set result [balanced_andor_tree 12]
do_faultsim_test fts3expr3-fault-1 -faults oom-* -body {
  test_fts3expr2 $::query
} -test {
  faultsim_test_result [list 0 $::result]
}

}

#-------------------------------------------------------------------

foreach {tn expr res} {
  1 {1 OR 2 OR 3 OR 4}           {OR {OR {P 1} {P 2}} {OR {P 3} {P 4}}} 
  2 {1 OR (2 AND 3 AND 4 AND 5)} 
    {OR {P 1} {AND {AND {P 2} {P 3}} {AND {P 4} {P 5}}}}
  3 {(2 AND 3 AND 4 AND 5) OR 1} 
    {OR {AND {AND {P 2} {P 3}} {AND {P 4} {P 5}}} {P 1}}

  4 {1 AND (2 OR 3 OR 4 OR 5)} 
    {AND {P 1} {OR {OR {P 2} {P 3}} {OR {P 4} {P 5}}}}
  5 {(2 OR 3 OR 4 OR 5) AND 1} 
    {AND {OR {OR {P 2} {P 3}} {OR {P 4} {P 5}}} {P 1}}

  6 {(2 OR 3 OR 4 OR 5) NOT 1} 
    {NOT {OR {OR {P 2} {P 3}} {OR {P 4} {P 5}}} {P 1}}

  7 {1 NOT (2 OR 3 OR 4 OR 5)} 
    {NOT {P 1} {OR {OR {P 2} {P 3}} {OR {P 4} {P 5}}}}

  8 {(1 OR 2 OR 3 OR 4) NOT (5 AND 6 AND 7 AND 8)}
    {NOT {OR {OR {P 1} {P 2}} {OR {P 3} {P 4}}} {AND {AND {P 5} {P 6}} {AND {P 7} {P 8}}}}
} {
  do_test 5.1.$tn {
    test_fts3expr2 $expr
  } $res
}

set sqlite_fts3_enable_parentheses 0
finish_test