struct InLoop {
        int iCur;              /* The VDBE cursor used by this IN operator */
        int addrInTop;         /* Top of the IN loop */
      } *aInLoop;           /* Information about each nested IN operator */
    } in;                 /* Used when plan.wsFlags&WHERE_IN_ABLE */
    Index *pCovidx;       /* Possible covering index for WHERE_MULTI_OR */
  } u;
  double rOptCost;      /* "Optimal" cost for this level */

  /* The following field is really not part of the current level.  But
  ** we need a place to cache virtual table index information for each
  ** virtual table in the FROM clause and the WhereLevel structure is
  ** a convenient place since there is one WhereLevel for each FROM clause
  ** element.
  */

        assert( sWBI.pSrc->pIndex==0 
                  || (sWBI.cost.plan.wsFlags & WHERE_NOT_FULLSCAN)==0
                  || sWBI.cost.plan.u.pIdx==sWBI.pSrc->pIndex );

        if( isOptimal && (sWBI.cost.plan.wsFlags & WHERE_NOT_FULLSCAN)==0 ){
          notIndexed |= m;
        }
        if( isOptimal ){
          pWInfo->a[j].rOptCost = sWBI.cost.rCost;
        }else if( iFrom<nTabList-1 ){
          /* If two or more tables have nearly the same outer loop cost,
          ** very different inner loop (optimal) cost, we want to choose
          ** for the outer loop that table which benefits the least from
          ** being in the inner loop.  The following code scales the 
          ** outer loop cost estimate to accomplish that. */
          WHERETRACE(("   scaling cost from %.1f to %.1f\n",
                      sWBI.cost.rCost,
                      sWBI.cost.rCost/pWInfo->a[j].rOptCost));
          sWBI.cost.rCost /= pWInfo->a[j].rOptCost;
        }

        /* Conditions under which this table becomes the best so far:
        **
        **   (1) The table must not depend on other tables that have not
        **       yet run.  (In other words, it must not depend on tables
        **       in inner loops.)
        **
        **   (2) (This rule was removed on 2012-11-09.  The scaling of the
        **       cost using the optimal scan cost made this rule obsolete.)
        **
        **   (3) All tables have an INDEXED BY clause or this table lacks an
        **       INDEXED BY clause or this table uses the specific
        **       index specified by its INDEXED BY clause.  This rule ensures
        **       that a best-so-far is always selected even if an impossible
        **       combination of INDEXED BY clauses are given.  The error
        **       will be detected and relayed back to the application later.
        **       The NEVER() comes about because rule (2) above prevents
        **       An indexable full-table-scan from reaching rule (3).
        **
        **   (4) The plan cost must be lower than prior plans, where "cost"
        **       is defined by the compareCost() function above. 
        */
        if( (sWBI.cost.used&sWBI.notValid)==0                    /* (1) */



            && (nUnconstrained==0 || sWBI.pSrc->pIndex==0        /* (3) */
                || NEVER((sWBI.cost.plan.wsFlags & WHERE_NOT_FULLSCAN)!=0))
            && (bestJ<0 || compareCost(&sWBI.cost, &bestPlan))   /* (4) */
        ){
          WHERETRACE(("   === table %d (%s) is best so far\n"
                      "       cost=%.1f, nRow=%.1f, nOBSat=%d, wsFlags=%08x\n",
                      j, sWBI.pSrc->pTab->zName,

        (NULL, 2, 1, 'two-a'),
        (NULL, 3, 1, 'three-a');
    COMMIT;
  }
} {}
do_test 1.1a {
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title, tn
  }
} {one-a one-c two-a two-b three-a three-c}

# Verify that the ORDER BY clause is optimized out
#
do_test 1.1b {
  db eval {
    EXPLAIN QUERY PLAN
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title, tn
  }
} {~/ORDER BY/}  ;# ORDER BY optimized out

# The same query with ORDER BY clause optimization disabled via + operators
# should give exactly the same answer.
#
do_test 1.2a {
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY +title, +tn
  }
} {one-a one-c two-a two-b three-a three-c}

# The output is sorted manually in this case.
#
do_test 1.2b {
  db eval {
    EXPLAIN QUERY PLAN
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY +title, +tn
  }
} {/ORDER BY/}   ;# separate sorting pass due to "+" on ORDER BY terms

# The same query with ORDER BY optimizations turned off via built-in test.
#
do_test 1.3a {
  optimization_control db order-by-idx-join 0
  db cache flush
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title, tn
  }
} {one-a one-c two-a two-b three-a three-c}
do_test 1.3b {
  db eval {
    EXPLAIN QUERY PLAN
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title, tn
  }
} {/ORDER BY/}   ;# separate sorting pass due to disabled optimization
optimization_control db all 1
db cache flush

# Reverse order sorts
#
do_test 1.4a {
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title DESC, tn
  }
} {three-a three-c two-a two-b one-a one-c}
do_test 1.4b {
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY +title DESC, +tn
  }
} {three-a three-c two-a two-b one-a one-c}  ;# verify same order after sorting
do_test 1.4c {
  db eval {
    EXPLAIN QUERY PLAN
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title DESC, tn
  }
} {~/ORDER BY/}  ;# optimized out


do_test 1.5a {
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title, tn DESC
  }
} {one-c one-a two-b two-a three-c three-a}
do_test 1.5b {
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY +title, +tn DESC
  }
} {one-c one-a two-b two-a three-c three-a}  ;# verify same order after sorting
do_test 1.5c {
  db eval {
    EXPLAIN QUERY PLAN
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title, tn DESC
  }
} {~/ORDER BY/}  ;# optimized out

do_test 1.6a {
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title DESC, tn DESC
  }
} {three-c three-a two-b two-a one-c one-a}
do_test 1.6b {
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY +title DESC, +tn DESC
  }
} {three-c three-a two-b two-a one-c one-a}  ;# verify same order after sorting
do_test 1.6c {
  db eval {
    EXPLAIN QUERY PLAN
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title DESC, tn DESC
  }
} {~/ORDER BY/}  ;# ORDER BY optimized-out


# Reconstruct the test data to use indices rather than integer primary keys.
#
do_test 2.0 {

        (20, 1, 'two-a'),
        (3,  1, 'three-a');
    COMMIT;
  }
} {}
do_test 2.1a {
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title, tn
  }
} {one-a one-c two-a two-b three-a three-c}

# Verify that the ORDER BY clause is optimized out
#
do_test 2.1b {
  db eval {
    EXPLAIN QUERY PLAN
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title, tn
  }
} {~/ORDER BY/}  ;# ORDER BY optimized out

do_test 2.1c {
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title, aid, tn
  }
} {one-a one-c two-a two-b three-a three-c}
do_test 2.1d {
  db eval {
    EXPLAIN QUERY PLAN
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title, aid, tn
  }
} {~/ORDER BY/}  ;# ORDER BY optimized out

# The same query with ORDER BY clause optimization disabled via + operators
# should give exactly the same answer.
#
do_test 2.2a {
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY +title, +tn
  }
} {one-a one-c two-a two-b three-a three-c}

# The output is sorted manually in this case.
#
do_test 2.2b {
  db eval {
    EXPLAIN QUERY PLAN
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY +title, +tn
  }
} {/ORDER BY/}   ;# separate sorting pass due to "+" on ORDER BY terms

# The same query with ORDER BY optimizations turned off via built-in test.
#
do_test 2.3a {
  optimization_control db order-by-idx-join 0
  db cache flush
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title, tn
  }
} {one-a one-c two-a two-b three-a three-c}
do_test 2.3b {
  db eval {
    EXPLAIN QUERY PLAN
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title, tn
  }
} {/ORDER BY/}   ;# separate sorting pass due to disabled optimization
optimization_control db all 1
db cache flush

# Reverse order sorts
#
do_test 2.4a {
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title DESC, tn
  }
} {three-a three-c two-a two-b one-a one-c}
do_test 2.4b {
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY +title DESC, +tn
  }
} {three-a three-c two-a two-b one-a one-c}  ;# verify same order after sorting
do_test 2.4c {
  db eval {
    EXPLAIN QUERY PLAN
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title DESC, tn
  }
} {~/ORDER BY/}  ;# optimized out


do_test 2.5a {
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title, tn DESC
  }
} {one-c one-a two-b two-a three-c three-a}
do_test 2.5b {
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY +title, +tn DESC
  }
} {one-c one-a two-b two-a three-c three-a}  ;# verify same order after sorting
do_test 2.5c {
  db eval {
    EXPLAIN QUERY PLAN
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title, tn DESC
  }
} {~/ORDER BY/}  ;# optimized out

do_test 2.6a {
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title DESC, tn DESC
  }
} {three-c three-a two-b two-a one-c one-a}
do_test 2.6b {
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY +title DESC, +tn DESC
  }
} {three-c three-a two-b two-a one-c one-a}  ;# verify same order after sorting
do_test 2.6c {
  db eval {
    EXPLAIN QUERY PLAN
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title DESC, tn DESC
  }
} {~/ORDER BY/}  ;# ORDER BY optimized out


# Generate another test dataset, but this time using mixed ASC/DESC indices.
#
do_test 3.0 {

        (NULL, 2, 1, 'two-a'),
        (NULL, 3, 1, 'three-a');
    COMMIT;
  }
} {}
do_test 3.1a {
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title, tn DESC
  }
} {one-c one-a two-b two-a three-c three-a}

# Verify that the ORDER BY clause is optimized out
#
do_test 3.1b {
  db eval {
    EXPLAIN QUERY PLAN
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title, tn DESC
  }
} {~/ORDER BY/}  ;# ORDER BY optimized out

# The same query with ORDER BY clause optimization disabled via + operators
# should give exactly the same answer.
#
do_test 3.2a {
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY +title, +tn DESC
  }
} {one-c one-a two-b two-a three-c three-a}

# The output is sorted manually in this case.
#
do_test 3.2b {
  db eval {
    EXPLAIN QUERY PLAN
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY +title, +tn DESC
  }
} {/ORDER BY/}   ;# separate sorting pass due to "+" on ORDER BY terms

# The same query with ORDER BY optimizations turned off via built-in test.
#
do_test 3.3a {
  optimization_control db order-by-idx-join 0
  db cache flush
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title, tn DESC
  }
} {one-c one-a two-b two-a three-c three-a}
do_test 3.3b {
  db eval {
    EXPLAIN QUERY PLAN
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title, tn DESC
  }
} {/ORDER BY/}   ;# separate sorting pass due to disabled optimization
optimization_control db all 1
db cache flush

# Without the mixed ASC/DESC on ORDER BY
#
do_test 3.4a {
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title, tn
  }
} {one-a one-c two-a two-b three-a three-c}
do_test 3.4b {
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY +title, +tn
  }
} {one-a one-c two-a two-b three-a three-c}  ;# verify same order after sorting
do_test 3.4c {
  db eval {
    EXPLAIN QUERY PLAN
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title, tn
  }
} {~/ORDER BY/}  ;# optimized out


do_test 3.5a {
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title DESC, tn DESC
  }
} {three-c three-a two-b two-a one-c one-a}
do_test 3.5b {
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY +title DESC, +tn DESC
  }
} {three-c three-a two-b two-a one-c one-a}  ;# verify same order after sorting
do_test 3.5c {
  db eval {
    EXPLAIN QUERY PLAN
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title DESC, tn DESC
  }
} {~/ORDER BY/}  ;# optimzed out


do_test 3.6a {
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title DESC, tn
  }
} {three-a three-c two-a two-b one-a one-c}
do_test 3.6b {
  db eval {
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY +title DESC, +tn
  }
} {three-a three-c two-a two-b one-a one-c}  ;# verify same order after sorting
do_test 3.6c {
  db eval {
    EXPLAIN QUERY PLAN
    SELECT name FROM album CROSS JOIN track USING (aid) ORDER BY title DESC, tn
  }
} {~/ORDER BY/}  ;# inverted ASC/DESC is optimized out


finish_test

# 2012 November 9
#
# 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.
#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this file is testing the query planner to make sure it
# is making good planning decisions.
#


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

do_execsql_test 1.1 {
  CREATE TABLE t1(a,b);
  INSERT INTO t1 VALUES(1,10), (2,20), (3,30), (2,22), (3, 33);
  INSERT INTO t1 SELECT * FROM t1;
  INSERT INTO t1 SELECT * FROM t1;
  INSERT INTO t1 SELECT * FROM t1;
  INSERT INTO t1 SELECT * FROM t1;
  INSERT INTO t1 SELECT * FROM t1;
  INSERT INTO t1 SELECT * FROM t1;
  INSERT INTO t1 SELECT * FROM t1;
  INSERT INTO t1 SELECT * FROM t1;
  INSERT INTO t1 SELECT * FROM t1;
  INSERT INTO t1 SELECT * FROM t1;
  ALTER TABLE t1 ADD COLUMN c;
  UPDATE t1 SET c=a*rowid+10000;
  CREATE INDEX t1ab ON t1(a,b);
  
  CREATE TABLE t2(x,y);
  INSERT INTO t2 VALUES(4,44),(5,55),(6,66),(7,77);
  INSERT INTO t2 SELECT x+4, (x+4)*11 FROM t2;
  INSERT INTO t2 SELECT x+8, (x+8)*11 FROM t2;
  INSERT INTO t2 SELECT x+16, (x+16)*11 FROM t2;
  INSERT INTO t2 SELECT x+32, (x+32)*11 FROM t2;
  INSERT INTO t2 SELECT x+64, (x+32)*11 FROM t2;
  ALTER TABLE t2 ADD COLUMN z;
  UPDATE t2 SET z=2;
  CREATE UNIQUE INDEX t2zx ON t2(z,x);

  EXPLAIN QUERY PLAN SELECT x FROM t1, t2 WHERE a=z AND c=x;
} {/.*SCAN TABLE t1 .*SEARCH TABLE t2 .*/}
do_execsql_test 1.2 {
  EXPLAIN QUERY PLAN SELECT x FROM t2, t1 WHERE a=z AND c=x;
} {/.*SCAN TABLE t1 .*SEARCH TABLE t2 .*/}
do_execsql_test 1.3 {
  ANALYZE;
  EXPLAIN QUERY PLAN SELECT x FROM t1, t2 WHERE a=z AND c=x;
} {/.*SCAN TABLE t1 .*SEARCH TABLE t2 .*/}
do_execsql_test 1.4 {
  EXPLAIN QUERY PLAN SELECT x FROM t2, t1 WHERE a=z AND c=x;
} {/.*SCAN TABLE t1 .*SEARCH TABLE t2 .*/}

finish_test

# 2012 November 9
#
# 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.
#
#***********************************************************************
# 
# Test cases for query planning decisions.


#
# The tests in this file demonstrate the behaviour of the query planner
# in determining the order in which joined tables are scanned.
#
# Assume there are two tables being joined - t1 and t2. Each has a cost
# if it is the outer loop, and a cost if it is the inner loop. As follows:
#
#   t1(outer) - cost of scanning t1 as the outer loop.
#   t1(inner) - cost of scanning t1 as the inner loop.
#   t2(outer) - cost of scanning t2 as the outer loop.
#   t2(inner) - cost of scanning t2 as the inner loop.
#
# Depending on the order in which the planner nests the scans, the total
# cost of the join query is one of:
#
#   t1(outer) * t2(inner)
#   t2(outer) * t1(inner)
#
# The tests in this file attempt to verify that the planner nests joins in
# the correct order when the following are true:
#
#   + (t1(outer) * t2(inner)) > (t1(inner) * t2(outer)
#   +  t1(outer) < t2(outer)
#
# In other words, when the best overall query plan has t2 as the outer loop,
# but when the outer loop is considered independent of the inner, t1 is the
# most efficient choice.
#
# In order to make them more predictable, automatic indexes are turned off for
# the tests in this file.
#

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

do_execsql_test 1.0 {
  PRAGMA automatic_index = 0;
  CREATE TABLE t1(a, b, c);
  CREATE TABLE t2(d, e, f);
  CREATE UNIQUE INDEX i1 ON t1(a);
  CREATE UNIQUE INDEX i2 ON t2(d);
} {}

foreach {tn sql} {
  1 "SELECT * FROM t1,           t2 WHERE t1.a=t2.e AND t2.d<t1.b AND t1.c!=10"
  2 "SELECT * FROM t2,           t1 WHERE t1.a=t2.e AND t2.d<t1.b AND t1.c!=10"
  3 "SELECT * FROM t2 CROSS JOIN t1 WHERE t1.a=t2.e AND t2.d<t1.b AND t1.c!=10"
} {
  do_test 1.$tn {
    db eval "EXPLAIN QUERY PLAN $sql"
   } {/.*SCAN TABLE t2 .*SEARCH TABLE t1 .*/}
}

do_execsql_test 2.0 {
  DROP TABLE t1;
  DROP TABLE t2;
  CREATE TABLE t1(a, b, c);
  CREATE TABLE t2(d, e, f);

  CREATE UNIQUE INDEX i1 ON t1(a);
  CREATE UNIQUE INDEX i2 ON t1(b);
  CREATE UNIQUE INDEX i3 ON t2(d);
} {}

foreach {tn sql} {
  1 "SELECT * FROM t1,           t2 WHERE t1.a>? AND t2.d>t1.c AND t1.b=t2.e"
  2 "SELECT * FROM t2,           t1 WHERE t1.a>? AND t2.d>t1.c AND t1.b=t2.e"
  3 "SELECT * FROM t2 CROSS JOIN t1 WHERE t1.a>? AND t2.d>t1.c AND t1.b=t2.e"
} {
  do_test 2.$tn {
    db eval "EXPLAIN QUERY PLAN $sql"
   } {/.*SCAN TABLE t2 .*SEARCH TABLE t1 .*/}
}

do_execsql_test 3.0 {
  DROP TABLE t1;
  DROP TABLE t2;
  CREATE TABLE t1(a, b, c);
  CREATE TABLE t2(d, e, f);

  CREATE UNIQUE INDEX i1 ON t1(a, b);
  CREATE INDEX i2 ON t2(d);
} {}

foreach {tn sql} {
  1 {SELECT t1.a, t1.b, t2.d, t2.e FROM t1, t2 
     WHERE t2.d=t1.b AND t1.a=(t2.d+1) AND t1.b = (t2.e+1)}

  2 {SELECT t1.a, t1.b, t2.d, t2.e FROM t2, t1 
     WHERE t2.d=t1.b AND t1.a=(t2.d+1) AND t1.b = (t2.e+1)}

  3 {SELECT t1.a, t1.b, t2.d, t2.e FROM t2 CROSS JOIN t1 
     WHERE t2.d=t1.b AND t1.a=(t2.d+1) AND t1.b = (t2.e+1)}
} {
  do_test 3.$tn {
    db eval "EXPLAIN QUERY PLAN $sql"
   } {/.*SCAN TABLE t2 .*SEARCH TABLE t1 .*/}
}

finish_test