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From:Dan Meany Date:August 3 2010 3:41pm
Subject:64 table join limit
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The 64 table limit on joins was discussed with a proposed solution based on the change to
key_map in the thread 16713 some time ago:  

http://lists.mysql.com/internals/16713

This has become much more of a constraint when implementing a partly schemaless design
with an attribute table (ala couchDb etc.) where you might need a self-join for every
field in the logical table.  I noticed the declaration ulonglong table_map is still in
both 5.1 and 5.4 vs. key_map which is Bitmap<64>.  I wonder if anyone has an
opinion if this is a safe change to make for table_map?





Thread
64 table join limitDan Meany3 Aug
  • Re: 64 table join limitMARK CALLAGHAN3 Aug
    • Re: 64 table join limitDan Meany3 Aug