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The table _does_ have a unique index on the combination of caseid and type, but I'm not sure if that is relevant.
by tyfon 10y ago
The table _does_ have a unique index on the combination of caseid and type, but I'm not sure if that is relevant.
- dsp1234 10y agoIt's possible, as the other commenters mentioned, it would come down to reviewing the query plan. I was just trying to address the two parts of your original comment, which were "is very baffeling" and "left join performance in sql server is very bad in some situations.". Hopefully my answer helped to un-baffel a little.