My host has limited size for MYSQL data bases and that means that one data base is going to fill quickly. I was told to split the reads and writes, but I can't find a script to do it.
I may not be understanding your problem, but I do not see how separating the reads and writes would solve your problem. If you are worried about the amount of data your provider allows you to store in your database, then separating the reads and writes would not help you at all. Separating them would just create complications with synchronizing them, and cause you to exceed your storage limits with two databases.
However, if you are going for performance, in regards to throughput, then having separate databases for reads and writes can make sense. If this is the case, you may also want to look at spreading your database across multiple computers, so that your application just sees one database. That said, you should not rely on scripts to synchronize the databases (a non-trivial task), you should rely on the database back-end for that.
Just want to make sure you're talking about databases and not tables.
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