Re: One big DB or two not-too-big DBs? FKs across DBs are slower?

[Daniel Liang]

Came across this not too long ago:

mysql> SELECT BENCHMARK(100000,myFunction('test'));
+-------------------------------------+
| BENCHMARK(100000,myFunction('test'))|
+-------------------------------------+
|                                   0 |
+-------------------------------------+

1 row in set (1.42 sec)

mysql> SELECT BENCHMARK(100000,database_2.myFunction('test'));
+-------------------------------------------------------------+
| BENCHMARK(100000,database_2.myFunction('test'))             |
+-------------------------------------------------------------+
|                                                           0 |
+-------------------------------------------------------------+

1 row in set (8.30 sec)


Functions in other database are slower than same functions within the "working" database.