Follow-up to fix for bug#25817660: Combination of virtual index, foreign key and trigger asserts

Dmitry Lenev · dahlerlend · commit 85a1c7bd03c2 · 2017-08-31T10:15:47.000+02:00
The problem which was solved by original patch for
handler::my_eval_gcolumn_expr_with_open() call affected
handler::my_prepare_gcolumn_template() call too.

The latter call too tried to initialize current LEX object
before trying to open table. This happened even during regular
processing and, indeed, destroyed the current statement context,
causing an assert error in dispatch_command().

Similarly to the original patch we solve the problem by
removing the calls to lex_start() and lex_end() from the
handler::my_prepare_gcolumn_template().
This is safe since neither of thd-&gt;dd_client()-&gt;acquire(),
open_table_uncached() nor innobase_build_v_templ_callback()
use the current LEX object.
diff --git a/mysql-test/r/foreign_key.result b/mysql-test/r/foreign_key.result
@@ -533,6 +533,17 @@ fld1
 SELECT * FROM t2;
 fld1	fld2
 2	2
+# The same test but with server restart before UPDATE.
+# Triggers different code path in InnoDB which was not
+# covered by original fix for the bug.
+# restart
+UPDATE t1 SET fld1= 3;
+SELECT * FROM t1;
+fld1
+3
+SELECT * FROM t2;
+fld1	fld2
+3	3
 DROP TABLE t2;
 DROP TABLE t1;
 #
diff --git a/mysql-test/suite/innodb/t/disabled.def b/mysql-test/suite/innodb/t/disabled.def
@@ -17,4 +17,3 @@ analyze_table           @solaris  : Bug#22607584 2016-03-01 Shaohua Failing too
 innodb.innodb_tsof_use_2  @windows : Bug#25716110 2017-03-14 Anitha Fails consistently on windows
 innodb.skip_locked_nowait  : Bug#25886814 2017-04-13 Allen Failing sporadically on PB2
 innodb.innodb_tsof_use_1  : Bug#26161492  2017-05-29 Erlend Fails sporadically
-virtual_fk_restart        : Bug#25817660 2017-04-01 dlenev Debug assertion due virtual column support code
diff --git a/mysql-test/t/foreign_key.test b/mysql-test/t/foreign_key.test
@@ -516,6 +516,16 @@ UPDATE t1 SET fld1= 2;
 SELECT * FROM t1;
 SELECT * FROM t2;
 
+--echo # The same test but with server restart before UPDATE.
+--echo # Triggers different code path in InnoDB which was not
+--echo # covered by original fix for the bug.
+
+--source include/restart_mysqld.inc
+UPDATE t1 SET fld1= 3;
+
+SELECT * FROM t1;
+SELECT * FROM t2;
+
 DROP TABLE t2;
 DROP TABLE t1;
 
diff --git a/sql/handler.cc b/sql/handler.cc
@@ -8773,7 +8773,6 @@ bool handler::my_prepare_gcolumn_template(THD *thd,
   build_table_filename(path, sizeof(path) - 1 - reg_ext_length,
                        db_name, table_name, "", 0, &was_truncated);
   DBUG_ASSERT(!was_truncated);
-  lex_start(thd);
   bool rc= true;
 
   MDL_ticket *mdl_ticket= NULL;
@@ -8805,7 +8804,6 @@ bool handler::my_prepare_gcolumn_template(THD *thd,
     intern_close_table(table);
     rc= false;
   }
-  lex_end(thd->lex);
   return rc;
 }
 

Original file line number	Diff line number	Diff line change
`@@ -8773,7 +8773,6 @@ bool handler::my_prepare_gcolumn_template(THD *thd,`
`8773`	`8773`	`build_table_filename(path, sizeof(path) - 1 - reg_ext_length,`
`8774`	`8774`	`db_name, table_name, "", 0, &was_truncated);`
`8775`	`8775`	`DBUG_ASSERT(!was_truncated);`
`8776`		`- lex_start(thd);`
`8777`	`8776`	`bool rc= true;`
`8778`	`8777`
`8779`	`8778`	`MDL_ticket *mdl_ticket= NULL;`
`@@ -8805,7 +8804,6 @@ bool handler::my_prepare_gcolumn_template(THD *thd,`
`8805`	`8804`	`intern_close_table(table);`
`8806`	`8805`	`rc= false;`
`8807`	`8806`	`}`
`8808`		`- lex_end(thd->lex);`
`8809`	`8807`	`return rc;`
`8810`	`8808`	`}`
`8811`	`8809`