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Use MySQL Information Schema carefully!

While working on a procedure which was running on dynamically created data table to derive one complex number, I observed one strange problem where MySQL was continuously eating memory and in spite of 35GB RAM, it was running out of memory after few hours.


After debugging the algorithm, it is found that we were querying on information_schema.columns to get the column name for each calculation and after 10,000 queries, it MySQL would start crawling and we had to restart it to release the memory. The issue is fixed by adding one static table containing column names which would be populated each time the data table got created dynamically.


But then it is interesting to observe this behavior of system table which uses the cache but does not close it fast! In fact one can optimize the usage of information schema referring MySQL official manual.

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