I use mysql Ver 14.12 Distrib 5.0.86, for unknown-linux-gnu (x86_64) using readline 5.1, I am seeing below query in the slow query logs:

# Time: 110907  7:00:09
# User@Host: XXX[XXX] @  [10.1.10.1]
# Query_time: 3  Lock_time: 0  Rows_sent: 1  Rows_examined: 347519
SET timestamp=1315378809;
# administrator command: Quit;

# User@Host: XXX[XXX] @  [10.1.10.1]
# Query_time: 3  Lock_time: 0  Rows_sent: 0  Rows_examined: 0
use XXX;
SET timestamp=1315378809;
# administrator command: Quit;

# User@Host: XXX[XXX] @  [10.1.10.1]
# Query_time: 3  Lock_time: 0  Rows_sent: 1  Rows_examined: 1
use XXX;
SET timestamp=1315378809;
# administrator command: Quit;

It is on a master, with one slave attached.

why SET timestamp in Slow query logs ? anyone can help me.