How would you expect AUTO_INCREMENT to work with MERGE tables ? Assuming INSERT_METHOD=LAST is used I would expect it to work same as in case insertion happens to the last table... which does not seems to be the case. Alternatively I would expect AUTO_INCREMENT to be based off the maximum value across all tables, respecting AUTO_INCREMENT set for the Merge Table itself. Neither of these expectations really true:
PLAIN TEXT SQL:
- mysql> CREATE TABLE a1(i int UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY);
- Query OK, 0 rows affected (0.01 sec)
- mysql> CREATE TABLE a2 LIKE a1;
- Query OK, 0 rows affected (0.00 sec)
- mysql> INSERT INTO a1 VALUES(2);
- Query OK, 1 row affected (0.00 …