A customer showed that a particular client reported a less-than-helpful error message when it tried to display some meta-data about a table.
I couldn’t repeat the behavior with just a copy of the schema, so I suspected it was because of the size of data in the customer’s server – somebody had used an int where they needed a long.
The customer’s data was quite large – many hundreds of GB – more than I could easily whip up on my laptop to test. But, I didn’t really need all that data, or even any data at all; I just needed MySQL to pretend it had all that data. Specifically, I needed information_schema to report a large data_length.
Enter Rewriter, the query rewrite plugin that ships …
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