3825 Sergey Glukhov 2012-05-12
Bug#13948247 DIVISION BY 0 IN GET_BEST_DISJUNCT_QUICK WITH FORCE INDEX GROUP BY
An attempt to create QUICK_SELECT object for empty table
(BLACKHOLE is always empty) leads to 'DIVISION BY 0' crash.
The fix is to skip QUICK_SELECT creation for empty table as
it's meaningless.
@ mysql-test/r/blackhole.result
test case
@ mysql-test/t/blackhole.test
test case
@ sql/opt_range.cc
skip QUICK_SELECT creation for empty table
modified:
mysql-test/r/blackhole.result
mysql-test/t/blackhole.test
sql/opt_range.cc
3824 Gleb Shchepa 2012-05-11
Bug #13906945: EXPLAIN JSON DISPLAYS ATTACHED CONDITION WRONGLY
IF INDEX_SUBQUERY
The value of the "attached_condition" string in JSON EXPLAIN
may display an outdated (unoptimized) expression text.
For top query, shallow_explain() writes attached_condition,
then explain_subqueries() runs JOIN::optimize() on subquery
which *transforms* subquery, so the subquery text printed
in top query's attached_condition becomes out-of-date.
The abstract "Lazy" class has been introduced to emulate
a lazy computation to evaluate expressions on demand.
The Lazy_condition successor for this class has been
introduced to defer Item tree pretty-printer call.
@ mysql-test/r/explain_json_all.result
New test.
Updates for old tests.
@ mysql-test/r/explain_json_none.result
New test.
Updates for old tests.
@ mysql-test/r/innodb_explain_json_non_select_all.result
Updates for old tests.
@ mysql-test/r/innodb_explain_json_non_select_none.result
Updates for old tests.
@ mysql-test/r/myisam_explain_json_non_select_all.result
Updates for old tests.
@ mysql-test/r/myisam_explain_json_non_select_none.result
Updates for old tests.
@ mysql-test/r/subquery_sj_mat_nosj.result
Updates for old tests.
@ mysql-test/r/subquery_sj_none.result
Updates for old tests.
@ mysql-test/r/subquery_sj_none_bka.result
Updates for old tests.
@ mysql-test/r/subquery_sj_none_bka_nixbnl.result
Updates for old tests.
@ mysql-test/r/subquery_sj_none_bkaunique.result
Updates for old tests.
@ sql/opt_explain.cc
* The Lazy_condition successor for the Lazy class has been
introduced to defer Item tree pretty-printer call.
* col_attached_condition string value has been replaced
with a deferred calculation object to compute it later.
@ sql/opt_explain_format.h
* The abstract "Lazy" class has been introduced to emulate
a lazy computation to evaluate procedures on demand.
* The mem_root_str class has been modified to accept
Lazy class object for further evaluation.
@ sql/opt_explain_traditional.cc
Minor update.
modified:
mysql-test/r/explain_json_all.result
mysql-test/r/explain_json_none.result
mysql-test/r/innodb_explain_json_non_select_all.result
mysql-test/r/innodb_explain_json_non_select_none.result
mysql-test/r/myisam_explain_json_non_select_all.result
mysql-test/r/myisam_explain_json_non_select_none.result
mysql-test/r/subquery_sj_mat_nosj.result
mysql-test/r/subquery_sj_none.result
mysql-test/r/subquery_sj_none_bka.result
mysql-test/r/subquery_sj_none_bka_nixbnl.result
mysql-test/r/subquery_sj_none_bkaunique.result
sql/opt_explain.cc
sql/opt_explain_format.h
sql/opt_explain_traditional.cc
=== modified file 'mysql-test/r/blackhole.result'
--- a/mysql-test/r/blackhole.result 2012-03-28 08:22:31 +0000
+++ b/mysql-test/r/blackhole.result 2012-05-12 08:31:02 +0000
@@ -9,3 +9,11 @@ SELECT 1 FROM t1 WHERE a = ANY (SELECT a
1
DROP TABLE t1, t2;
End of 5.5 tests
+#
+# Bug#13948247 DIVISION BY 0 IN GET_BEST_DISJUNCT_QUICK WITH FORCE INDEX GROUP BY
+#
+CREATE TABLE t1(a INT, b INT, c INT, KEY(c), UNIQUE(a)) ENGINE = BLACKHOLE;
+SELECT 0 FROM t1 FORCE INDEX FOR GROUP BY(a) WHERE a = 0 OR b = 0 AND c = 0;
+0
+DROP TABLE t1;
+End of 5.6 tests
=== modified file 'mysql-test/t/blackhole.test'
--- a/mysql-test/t/blackhole.test 2012-03-28 08:22:31 +0000
+++ b/mysql-test/t/blackhole.test 2012-05-12 08:31:02 +0000
@@ -19,3 +19,12 @@ DROP TABLE t1, t2;
--echo End of 5.5 tests
+--echo #
+--echo # Bug#13948247 DIVISION BY 0 IN GET_BEST_DISJUNCT_QUICK WITH FORCE INDEX GROUP BY
+--echo #
+
+CREATE TABLE t1(a INT, b INT, c INT, KEY(c), UNIQUE(a)) ENGINE = BLACKHOLE;
+SELECT 0 FROM t1 FORCE INDEX FOR GROUP BY(a) WHERE a = 0 OR b = 0 AND c = 0;
+DROP TABLE t1;
+
+--echo End of 5.6 tests
=== modified file 'sql/opt_range.cc'
--- a/sql/opt_range.cc 2012-05-09 16:47:39 +0000
+++ b/sql/opt_range.cc 2012-05-12 08:31:02 +0000
@@ -2817,7 +2817,8 @@ int SQL_SELECT::test_quick_select(THD *t
{
// Cannot return rows in descending order.
if (thd->optimizer_switch_flag(OPTIMIZER_SWITCH_INDEX_MERGE) &&
- interesting_order != ORDER::ORDER_DESC)
+ interesting_order != ORDER::ORDER_DESC &&
+ param.table->file->stats.records)
{
/* Try creating index_merge/ROR-union scan. */
SEL_IMERGE *imerge;
@@ -4218,6 +4219,8 @@ TABLE_READ_PLAN *get_best_disjunct_quick
DBUG_ENTER("get_best_disjunct_quick");
DBUG_PRINT("info", ("Full table scan cost: %g", read_time));
+ DBUG_ASSERT(param->table->file->stats.records);
+
Opt_trace_context * const trace= ¶m->thd->opt_trace;
Opt_trace_object trace_best_disjunct(trace);
if (!(range_scans= (TRP_RANGE**)alloc_root(param->mem_root,
No bundle (reason: useless for push emails).
| Thread |
|---|
| • bzr push into mysql-trunk branch (sergey.glukhov:3824 to 3825) Bug#13948247 | Sergey Glukhov | 21 May |
