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#
# Preparatory cleanup.
#
DROP TABLE IF EXISTS t1;
#
# We need a fixed timestamp to avoid varying results.
#
SET timestamp=1000000000;
#
# We need big packets.
#
# Capture initial value to reset at the end of the test
# Now adjust max_allowed_packet
SET @@global.max_allowed_packet= 1024*1024*1024;
max_allowed_packet is a global variable.
In order for the preceding change in max_allowed_packets' value
to be seen and used, we must start a new connection.
The change does not take effect with the current one.
For simplicity, we just disconnect / reconnect connection default here.
disconnect default;
connect default, localhost,root,,;
#
# Delete all existing binary logs.
#
RESET MASTER;
#
# Create a test table.
#
CREATE TABLE t1 (
c1 LONGTEXT
) ENGINE=MyISAM DEFAULT CHARSET latin1;
#
# Show how many rows are affected by each statement.
#
#
# Insert some big rows.
#
64MB
INSERT INTO t1 VALUES (REPEAT('ManyMegaByteBlck', 4194304));
affected rows: 1
32MB
INSERT INTO t1 VALUES (REPEAT('ManyMegaByteBlck', 2097152));
affected rows: 1
4MB
INSERT INTO t1 VALUES (REPEAT('ManyMegaByteBlck', 262144));
affected rows: 1
512KB
INSERT INTO t1 VALUES (REPEAT('ManyMegaByteBlck', 32768));
affected rows: 1
#
# Show what we have in the table.
# Do not display the column value itself, just its length.
#
SELECT LENGTH(c1) FROM t1;
LENGTH(c1) 67108864
LENGTH(c1) 33554432
LENGTH(c1) 4194304
LENGTH(c1) 524288
affected rows: 4
#
# Grow the rows by updating.
#
UPDATE t1 SET c1 = CONCAT(c1, c1);
affected rows: 4
info: Rows matched: 4 Changed: 4 Warnings: 0
#
# Show what we have in the table.
# Do not display the column value itself, just its length.
#
SELECT LENGTH(c1) FROM t1;
LENGTH(c1) 134217728
LENGTH(c1) 1048576
LENGTH(c1) 67108864
LENGTH(c1) 8388608
affected rows: 4
#
# Delete the rows.
#
DELETE FROM t1 WHERE c1 >= 'ManyMegaByteBlck';
affected rows: 4
#
# Hide how many rows are affected by each statement.
#
#
# Flush all log buffers to the log file.
#
FLUSH LOGS;
#
# Call mysqlbinlog to display the log file contents.
# NOTE: The output of mysqlbinlog is redirected to
# $MYSQLTEST_VARDIR/tmp/mysqlbinlog_big_1.out
# If you want to examine it, disable remove_file
# at the bottom of the test script.
#
#
# Cleanup.
#
# reset variable value to pass testcase checks
DROP TABLE t1;
remove_file $MYSQLTEST_VARDIR/tmp/mysqlbinlog_big_1.out
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