2

I want to compare two big tables if they are identical. If I update/insert one table into the other the process takes about 11 hours.

What I am looking for is like a sum function which sum ups a key for each row and then I would like to compare the two sums. I guess I would need to take every of the 40 columns into that key to be sure they are exactly the same.

Any idea how to do this quick? Ah I forgot one big thing: these tables are on different systems stored in different DMS. The source is DB2 and the copy is MySQL.

I read about the Checksum function in MySQL. - I also read, that it somewhat restricted to MyISAM - I reade that two tables with the same checksum could still have no identical content. -> might not be what I am looking for. Other ideas are apprechiated.

4
  • If you can export both as CSV (maybe explicitly ordered by the PK or something), then just DIFF them.
    – jkavalik
    Jan 5, 2016 at 13:48
  • Exporting to CSV, then using LOAD DATA would probably have decrease the transfer time significantly.
    – Rick James
    Jan 5, 2016 at 19:26
  • Thank you very much for your responses. How would you DIFF the two very large CSV files? Jan 7, 2016 at 13:44
  • With any diff tool, the commandline one might be well suited as afaik it does not load everything in memory.
    – jkavalik
    Jan 13, 2016 at 8:12

0

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Browse other questions tagged or ask your own question.