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Re: Optimized Indexing for a Schedule Table
Posted by: Wes Thompson
Date: November 25, 2010 11:05PM

I should also point some things out about the data if it helps

#1 Rows get updated quite often so there is lots of index churn
#2 Rows get inserted much less often
#3 Prio=0 means highest priority
#4 Typical usage patterns tend to bring the data in order when sorted on only the fire_time (and excluding priority) except for rows that never fire
#5 The prio column values are skews such that there are many more rows that have a high valued 'prio' entry
#6 There are quite a few rows with low priority (large prio) that never get updated because they are never "reached". Higher priority items tend to block them so they have fire_time values far in the past.

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