Fixed bug #27352.

The SELECT query with more than 31 nested dependent SELECT queries returned
wrong result.

New error message has been added: ER_TOO_HIGH_LEVEL_OF_NESTING_FOR_SELECT.
It will be reported as: "Too high level of nesting for select".


sql/sql_parse.cc:
  Fixed bug #27352.
  The Item_sum::register_sum_func method has been modified to return
  TRUE on exceeding of allowed level of SELECT nesting and to report
  corresponding error message.
sql/unireg.h:
  Fixed bug #27352.
  Constant definition has been added: maximal allowed level of SELECT nesting.
mysql-test/t/select.test:
  Updated test case for bug #27352.
mysql-test/r/select.result:
  Updated test case for bug #27352.
sql/share/errmsg.txt:
  Fixed bug #27352.
  New error message has been added: ER_TOO_HIGH_LEVEL_OF_NESTING_FOR_SELECT.

1 files changed, 30 insertions, 0 deletions

diff --git a/mysql-test/t/select.test b/mysql-test/t/select.test
index 56b2f1b02b8..8bfa12539fa 100644
--- a/mysql-test/t/select.test
+++ b/mysql-test/t/select.test
@@ -3370,4 +3370,34 @@ EXPLAIN SELECT COUNT(*) FROM t1 f1 INNER JOIN t1 f2
     WHERE 1 AND f1.b NOT IN (100,2232,3343,51111);
 DROP TABLE t1;    
 
+#
+# Bug #27352: Incorrect result of nested selects instead of error reporting
+#
+
+CREATE TABLE t1 (c1 INT, c2 INT);
+INSERT INTO t1 VALUES (1,11), (2,22), (2,22);
+
+let $n= 31;
+let $q= COUNT(c2);
+while ($n)
+{
+  let $q= (SELECT $q);
+  dec $n;
+}
+--disable_warnings
+eval EXPLAIN SELECT c1 FROM t1 WHERE $q > 0;
+--enable_warnings
+
+let $n= 64;
+let $q= COUNT(c2);
+while ($n)
+{
+  let $q= (SELECT $q);
+  dec $n;
+}
+--error ER_TOO_HIGH_LEVEL_OF_NESTING_FOR_SELECT
+eval EXPLAIN SELECT c1 FROM t1 WHERE $q > 0;
+
+DROP TABLE t1;
+
 --echo End of 5.0 tests