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# When the relay log gets rotated while the I/O thread
# is reading a transaction, the transaction spans on two or more
# relay logs. If STOP SLAVE occurs while the SQL thread is
# executing a part of the transaction in the non-first relay logs,
# we test if START SLAVE will resume in the beginning of the
# transaction (i.e., step back to the first relay log)
  
# The slave is started with max_binlog_size=16384 bytes,
# to force many rotations (approximately 30 rotations)

# We have to sync with master, to ensure slave had time to start properly
# before we stop it. If not, we get errors about UNIX_TIMESTAMP() in the log.
connection master;
sync_slave_with_master;
connection slave;
stop slave;
connection master;
--disable_warnings
eval create table t1 (a int) engine=$engine_type;
--enable_warnings
let $1=8000;
disable_query_log;
begin;
while ($1)
{
# eval means expand $ expressions
 eval insert into t1 values( $1 );
 dec $1;
}
commit;
# This will generate a 500kB master's binlog,
# which corresponds to 30 slave's relay logs.
enable_query_log;
save_master_pos;
connection slave;
reset slave;
start slave;
# We wait 1 sec for the SQL thread to be somewhere in
# the middle of the transaction, hopefully not in
# the first relay log, and hopefully before the COMMIT.
# Usually it stops when the SQL thread is around the 15th relay log.
# We cannot use MASTER_POS_WAIT() as master's position
# increases only when the slave executes the COMMIT.
# Note that except when using Valgrind, 1 second is enough for the I/O slave
# thread to fetch the whole master's binlog.
sleep 1;
stop slave;
# We suppose the SQL thread stopped before COMMIT.
# If so the transaction was rolled back
# and the table is now empty.
# Now restart
start slave;
# And see if the table contains '8000'
# which proves that the transaction restarted at
# the right place.
# We must wait for the transaction to commit before
# reading, with a sync_with_master.
sync_with_master;
select max(a) from t1;
connection master;

# The following DROP is a very important cleaning task:
# imagine the next test is run with --skip-innodb: it will do
# DROP TABLE IF EXISTS t1; but this will delete the frm and leave
# some data in the InnoDB datafile (because at that time mysqld
# does not know about InnoDB : --skip-innodb). So if later in the
# test suite a test wants to create an InnoDB table called t1, it
# will fail with 
# InnoDB: Error: table t1 already exists in InnoDB internal
# InnoDB: data dictionary. Have you deleted the .frm file etc
drop table t1;
# wait until this drop is executed on slave
save_master_pos;
connection slave;
sync_with_master;

# End of 4.1 tests