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MYSQL variables to tweak for queries fetching huge datasets

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  • MYSQL variables to tweak for queries fetching huge datasets


    SHOW varaible o/p
    VARIABLE_NAME VALUE
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  • #2
    For memory concern, the query result could either be buffered on the client side or on the server side. By default, results are sent to client as they are generated and get buffered on the client side. The C API function for that is mysql_store_result(). If the client doesn't have sufficient memory, you can buffer data on the server instead and fetch it row by row, that is what mysql_use_result() does. In this mode, it is better to have simple processing for each row to avoid tying up the server for too long. If you are using mysql program as the client, use the -q option to turn off caching on the client side. If you using some connector, check the corresponding functions.

    Also use the same max_allowed_packet for the client.

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