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test/cost.test
289 строк7 KB
drh
Do not reduce the estimated truth probability of LIKE and GLOB operators
02 фев 2026, 19:03
02 фев 2026, 19:0377c5456
# 2014-04-26
#
# 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.
#
#***********************************************************************
# 

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


do_execsql_test 1.1 {
  CREATE TABLE t3(id INTEGER PRIMARY KEY, b NOT NULL);
  CREATE TABLE t4(c, d, e);
  CREATE UNIQUE INDEX i3 ON t3(b);
  CREATE UNIQUE INDEX i4 ON t4(c, d);
}
do_eqp_test 1.2 {
  SELECT e FROM t3, t4 WHERE b=c ORDER BY b, d;
} {
  QUERY PLAN
  |--SCAN t3 USING COVERING INDEX i3
  `--SEARCH t4 USING INDEX i4 (c=?)
}


do_execsql_test 2.1 {
  CREATE TABLE t1(a, b);
  CREATE INDEX i1 ON t1(a);
}

# It is better to use an index for ORDER BY than sort externally, even 
# if the index is a non-covering index.
do_eqp_test 2.2 {
  SELECT * FROM t1 ORDER BY a;
} {SCAN t1 USING INDEX i1}

do_execsql_test 3.1 {
  CREATE TABLE t5(a INTEGER PRIMARY KEY,b,c,d,e,f,g);
  CREATE INDEX t5b ON t5(b);
  CREATE INDEX t5c ON t5(c);
  CREATE INDEX t5d ON t5(d);
  CREATE INDEX t5e ON t5(e);
  CREATE INDEX t5f ON t5(f);
  CREATE INDEX t5g ON t5(g);
}

do_eqp_test 3.2 {
  SELECT a FROM t5 
  WHERE b IS NULL OR c IS NULL OR d IS NULL 
  ORDER BY a;
} {
  QUERY PLAN
  |--MULTI-INDEX OR
  |  |--INDEX 1
  |  |  `--SEARCH t5 USING INDEX t5b (b=?)
  |  |--INDEX 2
  |  |  `--SEARCH t5 USING INDEX t5c (c=?)
  |  `--INDEX 3
  |     `--SEARCH t5 USING INDEX t5d (d=?)
  `--USE TEMP B-TREE FOR ORDER BY
}

#-------------------------------------------------------------------------
# If there is no likelihood() or stat3 data, SQLite assumes that a closed
# range scan (e.g. one constrained by "col BETWEEN ? AND ?" constraint)
# visits 1/64 of the rows in a table.
#
# Note: 1/63 =~ 0.016
# Note: 1/65 =~ 0.015
#
reset_db
do_execsql_test 4.1 {
  CREATE TABLE t1(a, b);
  CREATE INDEX i1 ON t1(a);
  CREATE INDEX i2 ON t1(b);
}
do_eqp_test 4.2 {
  SELECT * FROM t1 WHERE likelihood(a=?, 0.014) AND b BETWEEN ? AND ?;
} {SEARCH t1 USING INDEX i1 (a=?)}

do_eqp_test 4.3 {
  SELECT * FROM t1 WHERE likelihood(a=?, 0.016) AND b BETWEEN ? AND ?;
} {SEARCH t1 USING INDEX i2 (b>? AND b<?)}


#-------------------------------------------------------------------------
#
reset_db
do_execsql_test 5.1 {
  CREATE TABLE t2(x, y);
  CREATE INDEX t2i1 ON t2(x);
}

do_eqp_test 5.2 {
  SELECT * FROM t2 ORDER BY x, y;
} {
  QUERY PLAN
  |--SCAN t2 USING INDEX t2i1
  `--USE TEMP B-TREE FOR LAST TERM OF ORDER BY
}

do_eqp_test 5.3 {
  SELECT * FROM t2 WHERE x BETWEEN ? AND ? ORDER BY rowid;
} {
  QUERY PLAN
  |--SEARCH t2 USING INDEX t2i1 (x>? AND x<?)
  `--USE TEMP B-TREE FOR ORDER BY
}

# where7.test, where8.test:
#
do_execsql_test 6.1 {
  CREATE TABLE t3(a INTEGER PRIMARY KEY, b, c);
  CREATE INDEX t3i1 ON t3(b);
  CREATE INDEX t3i2 ON t3(c);
}

do_eqp_test 6.2 {
  SELECT a FROM t3 WHERE (b BETWEEN 2 AND 4) OR c=100 ORDER BY a
} {
  QUERY PLAN
  |--MULTI-INDEX OR
  |  |--INDEX 1
  |  |  `--SEARCH t3 USING INDEX t3i1 (b>? AND b<?)
  |  `--INDEX 2
  |     `--SEARCH t3 USING INDEX t3i2 (c=?)
  `--USE TEMP B-TREE FOR ORDER BY
}

#-------------------------------------------------------------------------
#
reset_db
do_execsql_test 7.1 {
  CREATE TABLE t1(a INTEGER PRIMARY KEY,b,c,d,e,f,g);
  CREATE INDEX t1b ON t1(b);
  CREATE INDEX t1c ON t1(c);
  CREATE INDEX t1d ON t1(d);
  CREATE INDEX t1e ON t1(e);
  CREATE INDEX t1f ON t1(f);
  CREATE INDEX t1g ON t1(g);
}

do_eqp_test 7.2 {
  SELECT a FROM t1
     WHERE (b>=950 AND b<=1010) OR (b IS NULL AND c NOT NULL)
  ORDER BY a
} {
  QUERY PLAN
  |--MULTI-INDEX OR
  |  |--INDEX 1
  |  |  `--SEARCH t1 USING INDEX t1b (b>? AND b<?)
  |  `--INDEX 2
  |     `--SEARCH t1 USING INDEX t1b (b=?)
  `--USE TEMP B-TREE FOR ORDER BY
}

do_eqp_test 7.3 {
  SELECT rowid FROM t1
  WHERE (+b IS NULL AND c NOT NULL AND d NOT NULL)
        OR (b NOT NULL AND c IS NULL AND d NOT NULL)
        OR (b NOT NULL AND c NOT NULL AND d IS NULL)
} {SCAN t1}

do_eqp_test 7.4 {
  SELECT rowid FROM t1 WHERE (+b IS NULL AND c NOT NULL) OR c IS NULL
} {SCAN t1}

#-------------------------------------------------------------------------
#
reset_db
do_execsql_test 8.1 {
  CREATE TABLE composer(
    cid INTEGER PRIMARY KEY,
    cname TEXT
  );
  CREATE TABLE album(
    aid INTEGER PRIMARY KEY,
    aname TEXT
  );
  CREATE TABLE track(
    tid INTEGER PRIMARY KEY,
    cid INTEGER REFERENCES composer,
    aid INTEGER REFERENCES album,
    title TEXT
  );
  CREATE INDEX track_i1 ON track(cid);
  CREATE INDEX track_i2 ON track(aid);
}

do_eqp_test 8.2 {
  SELECT DISTINCT aname
    FROM album, composer, track
   WHERE cname LIKE '%bach%'
     AND unlikely(composer.cid=track.cid)
     AND unlikely(album.aid=track.aid);
} {
  QUERY PLAN
  |--SCAN track
  |--SEARCH composer USING INTEGER PRIMARY KEY (rowid=?)
  |--SEARCH album USING INTEGER PRIMARY KEY (rowid=?)
  `--USE TEMP B-TREE FOR DISTINCT
}

#-------------------------------------------------------------------------
#
do_execsql_test 9.1 {
  CREATE TABLE t1(
    a,b,c,d,e, f,g,h,i,j,
    k,l,m,n,o, p,q,r,s,t
  );
  CREATE INDEX i1 ON t1(k,l,m,n,o,p,q,r,s,t);
}
do_test 9.2 {
  for {set i 0} {$i < 100} {incr i} {
    execsql { INSERT INTO t1 DEFAULT VALUES }
  }
  execsql {
    ANALYZE;
    CREATE INDEX i2 ON t1(a,b,c,d,e,f,g,h,i,j);
  }
} {}

set L [list a=? b=? c=? d=? e=? f=? g=? h=? i=? j=?]
foreach {tn nTerm nRow} {
  1   1 10
  2   2 10
  3   3  8
  4   4  7
  5   5  7
  6   6  5
  7   7  5
  8   8  5
  9   9  5
  10 10  5
} {
  set w [join [lrange $L 0 [expr $nTerm-1]] " AND "]
  set p1 [expr ($nRow-1) / 100.0]
  set p2 [expr ($nRow+1) / 100.0]

  set sql1 "SELECT * FROM t1 WHERE likelihood(k=?, $p1) AND $w"
  set sql2 "SELECT * FROM t1 WHERE likelihood(k=?, $p2) AND $w"

  do_eqp_test 9.3.$tn.1 $sql1 {/INDEX i1/}
  do_eqp_test 9.3.$tn.2 $sql2 {/INDEX i2/}
}


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

ifcapable stat4 {
  do_execsql_test 10.1 {
    CREATE TABLE t6(a, b, c);
    CREATE INDEX t6i1 ON t6(a, b);
    CREATE INDEX t6i2 ON t6(c);
  }
  
  do_test 10.2 {
    for {set i 0} {$i < 16} {incr i} {
      execsql { INSERT INTO t6 VALUES($i%4, 'xyz', $i%8) }
    }
    execsql ANALYZE
  } {}

  do_eqp_test 10.3 {
    SELECT rowid FROM t6 WHERE a=0 AND c=0
  } {SEARCH t6 USING INDEX t6i2 (c=?)}

  do_eqp_test 10.4 {
    SELECT rowid FROM t6 WHERE a=0 AND b='xyz' AND c=0
  } {SEARCH t6 USING INDEX t6i2 (c=?)}

  do_eqp_test 10.5 {
    SELECT rowid FROM t6 WHERE likelihood(a=0, 0.1) AND c=0
  } {SEARCH t6 USING INDEX t6i1 (a=?)}

  do_eqp_test 10.6 {
    SELECT rowid FROM t6 WHERE likelihood(a=0, 0.1) AND b='xyz' AND c=0
  } {SEARCH t6 USING INDEX t6i1 (a=? AND b=?)}
}

finish_test