~drizzle-trunk/drizzle/development

  • Committer: Stewart Smith
  • Date: 2010-08-12 16:48:46 UTC
  • Revision ID: stewart@flamingspork.com-20100812164846-s9bhy47g60bvqs41
bug lp:611379 Equivalent queries with Impossible where return different results

The following two equivalent queries return different results in maria 5.2 and 5.3 (and identical results in mysql 5.5.5) :

SELECT SUM( DISTINCT table1 .`pk` ) FROM B table1 STRAIGHT_JOIN ( BB table2 JOIN CC ON table2 .`col_varchar_key` ) ON table2 .`pk` ;

SELECT * FROM ( SELECT SUM( DISTINCT table1 .`pk` ) FROM B table1 STRAIGHT_JOIN ( BB table2 JOIN CC ON table2 .`col_varchar_key` ) ON table2 .`pk` );

MariaDB returns 0 on the second query and NULL on the first, whereas MySQL returns NULL on both. In MariaDB, both EXPLAIN plans agree that "Impossible WHERE noticed after reading const tables"



We have some slightly different output in drizzle:

main.bug_lp611379 [ fail ]
drizzletest: At line 9: query 'explain select * from (select sum(distinct t1.a) from t1,t2 where t1.a=t2.a)
as t' failed: 1048: Column 'sum(distinct t1.a)' cannot be null

but the fix gets us the correct query results, although with slightly different execution plans.



This fix is directly ported from MariaDB.
Filename Latest Rev Last Changed Committer Comment Size
..
My 1 16 years ago brian clean slate Diff
mtr_cases.pl 1644.1.5 14 years ago Monty Taylor Added support for per-suite master.opt file. 23.2 KB Diff Download File
mtr_diff.pl 1 16 years ago brian clean slate 7.4 KB Diff Download File
mtr_gcov.pl 1233.2.1 15 years ago Monty Taylor Renamed instances of HEAP engine to MEMORY. Remove 1.8 KB Diff Download File
mtr_gprof.pl 1 16 years ago brian clean slate 1.8 KB Diff Download File
mtr_im.pl 1 16 years ago brian clean slate 18.2 KB Diff Download File
mtr_io.pl 1 16 years ago brian clean slate 5.5 KB Diff Download File
mtr_match.pl 1 16 years ago brian clean slate 2 KB Diff Download File
mtr_misc.pl 1 16 years ago brian clean slate 6.2 KB Diff Download File
mtr_process.pl 1567.1.2 15 years ago Brian Aker 1) Fix assignment find by G++ pendatic. 2) Fix tes 27.7 KB Diff Download File
mtr_report.pl 1418.1.3 15 years ago Monty Taylor Removed the bit from test-run where we grep some s 8.8 KB Diff Download File
mtr_stress.pl 1 16 years ago brian clean slate 5.8 KB Diff Download File
mtr_timer.pl 1 16 years ago brian clean slate 4 KB Diff Download File
mtr_unique.pl 1 16 years ago brian clean slate 4.4 KB Diff Download File