On Tue, 6 Sep 2005, Dan Nelson wrote:
> In the last episode (Sep 06), Jason Pyeron said:
>> there is an unique key index 'pathref_2 (pathref,version)' on this
>> so why does 'explain select * from files where
>> (pathref,version)=(129286,0);' scan the whole table?
> I have to admit I have never seen this syntax used in a where clause
never thought not to use it, SQL servers are just big set processing
> Does "where pathref=129286 and version=0" optimize any better?
yes, it scans only one row.
> A quick test of mysql-5.0.11 indicates that it doesn't use indexes at
> all with the (field1,field2,..)=(value1,value2,..) syntax. Feel free
> to file a bug :)
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