How-to-repeat :
mysql> CREATE TABLE test (i int unsigned NOT NULL, l bigint unsigned NOT NULL);
# Insert a very big int (inside 64bit bounds, of course)
mysql> INSERT INTO test VALUES ('4711','4711000000000000001');
# Find it!
mysql> SELECT * FROM test WHERE l>'4711000000000000000';
Empty set (0.00 sec)
# Umm - but this works!
mysql> SELECT * FROM test WHERE l>4711000000000000000;
+------+---------------------+
| i | l |
+------+---------------------+
| 4711 | 4711000000000000001 |
+------+---------------------+
1 row in set (0.00 sec)