Actually the op was asking about efficiency. If the databases are on the same machine using mysql as he stated, then it is more efficient to have one connection to one database. If the data grows to the point that you can't keep it all on one machine then you can be more efficient by partitioning it into different databases on different machines.

In reply to Re^3: Connecting to Multiple Databases vs A Single One by cowboy
in thread Connecting to Multiple Databases vs A Single One by Anonymous Monk

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