main.percona_userstat fails sporadically

[Yura Sorokin]

_StringException: Text attachment: traceback
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Comment:

Logfile:
CURRENT_TEST: main.percona_userstat
mysqltest: At line 121: query 'SELECT
Select_commands, Update_commands, Other_commands, Rows_fetched
INTO
@initial_select_commands, @initial_update_commands, @initial_other_commands, @initial_rows_fetched
FROM
INFORMATION_SCHEMA.USER_STATISTICS
' failed: 1172: Result consisted of more than one row

The result from queries just before the failure was:
< snip >
ROWS_READ
10
FLUSH INDEX_STATISTICS;
SELECT ROWS_READ FROM INFORMATION_SCHEMA.INDEX_STATISTICS WHERE TABLE_NAME='t1';
ROWS_READ
SELECT COUNT(*) FROM t1;
COUNT(*)
10
SELECT ROWS_READ FROM INFORMATION_SCHEMA.TABLE_STATISTICS WHERE TABLE_NAME='t1';
ROWS_READ
10
SELECT ROWS_READ FROM INFORMATION_SCHEMA.INDEX_STATISTICS WHERE TABLE_NAME='t1';
ROWS_READ
10
DROP TABLE t1;
CREATE TABLE t2 (c1 INT UNSIGNED) ENGINE=InnoDB;
ALTER TABLE t2 MODIFY c1 FLOAT;
SELECT * FROM INFORMATION_SCHEMA.TABLE_STATISTICS WHERE TABLE_NAME='t2';
TABLE_SCHEMA TABLE_NAME ROWS_READ ROWS_CHANGED ROWS_CHANGED_X_INDEXES
DROP TABLE t2;

More results from queries before failure can be found in /mnt/workspace/percona-server-5.5-param/BUILD_TYPE/debug/Host/debian-jessie-64bit/mysql-test/var/2/log/percona_userstat.log
------------

[Yura Sorokin (yura-sorokin)]

https://github.com/percona/percona-server/pull/241
https://github.com/percona/percona-server/pull/242

[Shahriyar Rzayev (rzayev-sehriyar)]

Percona now uses JIRA for bug reports so this bug report is migrated to: https://jira.percona.com/browse/PS-2131