[MonetDB-users] Timestamp performance
Hi,
How fast are join operations on timestamp fields compared to joins on int/bigint fields? I thought about using timestamp.unix_epoch to store numbers instead of timestamps to speed up joins, but if timestamp joins are just as fast then that wouldn't be necessary.
Thanks.
On Wed, May 13, 2009 at 05:07:03AM -0700, Alex Bo. wrote:
Hi,
How fast are join operations on timestamp fields compared to joins on int/bigint fields? I thought about using timestamp.unix_epoch to store numbers instead of timestamps to speed up joins, but if timestamp joins are just as fast then that wouldn't be necessary.
There should not be any type-specific join performance difference between int & timestamps --- in case of doubt, just test it ;-)
Stefan
Thanks.
View this message in context: http://www.nabble.com/Timestamp-performance-tp23520512p23520512.html Sent from the monetdb-users mailing list archive at Nabble.com.
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Hi,
timestamps are stored as integers internally in MonetDB. As such, the join operations should have the same cost. However, I am not aware if the sql optimizer has different optimization techniques depending the type of the attributes to be joined, but I highly doubt it to be that the case for timestamps vs. bigints.
lefteris
On Wed, May 13, 2009 at 2:07 PM, Alex Bo. alex.bodinner@gmail.com wrote:
Hi,
How fast are join operations on timestamp fields compared to joins on int/bigint fields? I thought about using timestamp.unix_epoch to store numbers instead of timestamps to speed up joins, but if timestamp joins are just as fast then that wouldn't be necessary.
Thanks.
View this message in context: http://www.nabble.com/Timestamp-performance-tp23520512p23520512.html Sent from the monetdb-users mailing list archive at Nabble.com.
The NEW KODAK i700 Series Scanners deliver under ANY circumstances! Your production scanning environment may not be a perfect world - but thanks to Kodak, there's a perfect scanner to get the job done! With the NEW KODAK i700 Series Scanner you'll get full speed at 300 dpi even with all image processing features enabled. http://p.sf.net/sfu/kodak-com _______________________________________________ MonetDB-users mailing list MonetDB-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/monetdb-users
participants (3)
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Alex Bo.
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Lefteris
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Stefan Manegold