github.com/jdgcs/sqlite3@v1.12.1-0.20210908114423-bc5f96e4dd51/testdata/tcl/analyzeC.test

# 2014-07-22
#
# 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 contains automated tests used to verify that the text terms
# at the end of sqlite_stat1.stat are processed correctly.
#
#  (1) "unordered" means that the index cannot be used for ORDER BY
#      or for range queries
#
#  (2) "sz=NNN" sets the relative size of the index entries
#
#  (3) All other fields are silently ignored
#

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

# Baseline case.  Range queries work OK.  Indexes can be used for
# ORDER BY.
#
do_execsql_test 1.0 {
  CREATE TABLE t1(a,b,c);
  INSERT INTO t1(a,b,c)
    VALUES(1,2,3),(7,8,9),(4,5,6),(10,11,12),(4,8,12),(1,11,111);
  CREATE INDEX t1a ON t1(a);
  CREATE INDEX t1b ON t1(b);
  ANALYZE;
  DELETE FROM sqlite_stat1;
  INSERT INTO sqlite_stat1(tbl,idx,stat)
    VALUES('t1','t1a','12345 2'),('t1','t1b','12345 4');
  ANALYZE sqlite_master;
  SELECT *, '#' FROM t1 WHERE a BETWEEN 3 AND 8 ORDER BY c;
} {4 5 6 # 7 8 9 # 4 8 12 #}
do_execsql_test 1.1 {
  EXPLAIN QUERY PLAN
  SELECT *, '#' FROM t1 WHERE a BETWEEN 3 AND 8 ORDER BY c;
} {/.* USING INDEX t1a .a>. AND a<...*/}
do_execsql_test 1.2 {
  SELECT c FROM t1 ORDER BY a;
} {3 111 6 12 9 12}
do_execsql_test 1.3 {
  EXPLAIN QUERY PLAN
  SELECT c FROM t1 ORDER BY a;
} {/.*SCAN t1 USING INDEX t1a.*/}
do_execsql_test 1.3x {
  EXPLAIN QUERY PLAN
  SELECT c FROM t1 ORDER BY a;
} {~/.*B-TREE FOR ORDER BY.*/}

# Now mark the t1a index as "unordered".  Range queries and ORDER BY no
# longer use the index, but equality queries do.
#
do_execsql_test 2.0 {
  UPDATE sqlite_stat1 SET stat='12345 2 unordered' WHERE idx='t1a';
  ANALYZE sqlite_master;
  SELECT *, '#' FROM t1 WHERE a BETWEEN 3 AND 8 ORDER BY c;
} {4 5 6 # 7 8 9 # 4 8 12 #}
do_execsql_test 2.1 {
  EXPLAIN QUERY PLAN
  SELECT *, '#' FROM t1 WHERE a BETWEEN 3 AND 8 ORDER BY c;
} {~/.*USING INDEX.*/}
do_execsql_test 2.2 {
  SELECT c FROM t1 ORDER BY a;
} {3 111 6 12 9 12}
do_execsql_test 2.3 {
  EXPLAIN QUERY PLAN
  SELECT c FROM t1 ORDER BY a;
} {~/.*USING INDEX.*/}
do_execsql_test 2.3x {
  EXPLAIN QUERY PLAN
  SELECT c FROM t1 ORDER BY a;
} {/.*B-TREE FOR ORDER BY.*/}

# Ignore extraneous text parameters in the sqlite_stat1.stat field.
#
do_execsql_test 3.0 {
  UPDATE sqlite_stat1 SET stat='12345 2 whatever=5 unordered xyzzy=11'
   WHERE idx='t1a';
  ANALYZE sqlite_master;
  SELECT *, '#' FROM t1 WHERE a BETWEEN 3 AND 8 ORDER BY c;
} {4 5 6 # 7 8 9 # 4 8 12 #}
do_execsql_test 3.1 {
  EXPLAIN QUERY PLAN
  SELECT *, '#' FROM t1 WHERE a BETWEEN 3 AND 8 ORDER BY c;
} {~/.*USING INDEX.*/}
do_execsql_test 3.2 {
  SELECT c FROM t1 ORDER BY a;
} {3 111 6 12 9 12}
do_execsql_test 3.3 {
  EXPLAIN QUERY PLAN
  SELECT c FROM t1 ORDER BY a;
} {~/.*USING INDEX.*/}
do_execsql_test 3.3x {
  EXPLAIN QUERY PLAN
  SELECT c FROM t1 ORDER BY a;
} {/.*B-TREE FOR ORDER BY.*/}

# The sz=NNN parameter determines which index to scan
#
do_execsql_test 4.0 {
  DROP INDEX t1a;
  CREATE INDEX t1ab ON t1(a,b);
  CREATE INDEX t1ca ON t1(c,a);
  DELETE FROM sqlite_stat1;
  INSERT INTO sqlite_stat1(tbl,idx,stat)
    VALUES('t1','t1ab','12345 3 2 sz=10'),('t1','t1ca','12345 3 2 sz=20');
  ANALYZE sqlite_master;
  SELECT count(a) FROM t1;
} {6}
do_execsql_test 4.1 {
  EXPLAIN QUERY PLAN
  SELECT count(a) FROM t1;
} {/.*INDEX t1ab.*/}
do_execsql_test 4.2 {
  DELETE FROM sqlite_stat1;
  INSERT INTO sqlite_stat1(tbl,idx,stat)
    VALUES('t1','t1ab','12345 3 2 sz=20'),('t1','t1ca','12345 3 2 sz=10');
  ANALYZE sqlite_master;
  SELECT count(a) FROM t1;
} {6}
do_execsql_test 4.3 {
  EXPLAIN QUERY PLAN
  SELECT count(a) FROM t1;
} {/.*INDEX t1ca.*/}

# 2019-08-15.
# Ticket https://www.sqlite.org/src/tktview/e4598ecbdd18bd82945f602901
# The sz=N parameter in the sqlite_stat1 table needs to have a value of
# 2 or more to avoid a division by zero in the query planner.
#
do_execsql_test 4.4 {
  DROP TABLE IF EXISTS t44;
  CREATE TABLE t44(a PRIMARY KEY);
  INSERT INTO sqlite_stat1 VALUES('t44',null,'sz=0');
  ANALYZE sqlite_master;
  SELECT 0 FROM t44 WHERE a IN(1,2,3);
} {}



# The sz=NNN parameter works even if there is other extraneous text
# in the sqlite_stat1.stat column.
#
do_execsql_test 5.0 {
  DELETE FROM sqlite_stat1;
  INSERT INTO sqlite_stat1(tbl,idx,stat)
    VALUES('t1','t1ab','12345 3 2 x=5 sz=10 y=10'),
          ('t1','t1ca','12345 3 2 whatever sz=20 junk');
  ANALYZE sqlite_master;
  SELECT count(a) FROM t1;
} {6}
do_execsql_test 5.1 {
  EXPLAIN QUERY PLAN
  SELECT count(a) FROM t1;
} {/.*INDEX t1ab.*/}
do_execsql_test 5.2 {
  DELETE FROM sqlite_stat1;
  INSERT INTO sqlite_stat1(tbl,idx,stat)
    VALUES('t1','t1ca','12345 3 2 x=5 sz=10 y=10'),
          ('t1','t1ab','12345 3 2 whatever sz=20 junk');
  ANALYZE sqlite_master;
  SELECT count(a) FROM t1;
} {6}
do_execsql_test 5.3 {
  EXPLAIN QUERY PLAN
  SELECT count(a) FROM t1;
} {/.*INDEX t1ca.*/}




finish_test