^^&&^^

Edit File: merge-big.test

#
# Test of MERGE tables with multisession and many waits.
#
# This test takes rather long time so let us run it only in --big-test mode
--source include/big_test.inc
# We use some debug-only features in this test
--source include/have_debug.inc
# We use INFORMATION_SCHEMA.PROCESSLIST in this test
--source include/not_embedded.inc

--disable_warnings
drop table if exists t1,t2,t3,t4,t5,t6;
--enable_warnings

--echo #
--echo # Bug#26379 - Combination of FLUSH TABLE and REPAIR TABLE
--echo #             corrupts a MERGE table
--echo # Problem #3
--echo #
# Two FLUSH TABLES within a LOCK TABLES segment could invalidate the lock.
# This did *not* require a MERGE table.
#
# To increase reproducibility it was necessary to enter a sleep of 2
# seconds at the end of wait_for_tables() after unlock of LOCK_open. In
# 5.0 and 5.1 the sleep must be inserted in open_and_lock_tables() after
# open_tables() instead. wait_for_tables() is not used in this case. The
# problem was that FLUSH TABLES releases LOCK_open while having unlocked
# and closed all tables. When this happened while a thread was in the
# loop in mysql_lock_tables() right after wait_for_tables()
# (open_tables()) and before retrying to lock, the thread got the lock.
# And it did not notice that the table needed a refresh after the
# [re-]open. So it executed its statement on the table.
#
# The first FLUSH TABLES kicked the INSERT out of thr_multi_lock() and
# let it wait in wait_for_tables() (open_table()). The second FLUSH
# TABLES must happen while the INSERT was on its way from
# wait_for_tables() (open_table()) to the next call of thr_multi_lock().
# This needed to be supported by a sleep to make it repeatable.
#
CREATE TABLE t1 (c1 INT) ENGINE= MyISAM;
LOCK TABLE t1 WRITE;
#SELECT NOW();
    --echo # connection con1
    connect (con1,localhost,root,,);
    let $con1_id= `SELECT CONNECTION_ID()`;
    SET SESSION debug="+d,sleep_open_and_lock_after_open";
    send INSERT INTO t1 VALUES (1);
--echo # connection default
connection default;
--echo # Let INSERT go into thr_multi_lock().
#--sleep 8
#SELECT ID,STATE,INFO FROM INFORMATION_SCHEMA.PROCESSLIST;
let $wait_condition= SELECT 1 FROM INFORMATION_SCHEMA.PROCESSLIST
    WHERE ID = $con1_id AND STATE = 'Waiting for table metadata lock';
--source include/wait_condition.inc
#SELECT NOW();
--echo # Kick INSERT out of thr_multi_lock().
FLUSH TABLES;
#SELECT NOW();
--echo # Let INSERT go through open_tables() where it sleeps.
#--sleep 8
#SELECT ID,STATE,INFO FROM INFORMATION_SCHEMA.PROCESSLIST;
let $wait_condition= SELECT 1 FROM INFORMATION_SCHEMA.PROCESSLIST
    WHERE ID = $con1_id AND STATE = 'Waiting for table metadata lock';
--source include/wait_condition.inc
#SELECT NOW();
--echo # Unlock and close table and wait for con1 to close too.
FLUSH TABLES;
#SELECT NOW();
--echo # This should give no result.
SELECT * FROM t1;
#SELECT NOW();
UNLOCK TABLES;
    --echo # connection con1
    connection con1;
    reap;
    SET SESSION debug="-d,sleep_open_and_lock_after_open";
    disconnect con1;
--echo # connection default
connection default;
DROP TABLE t1;