[Progress Communities] [Progress OpenEdge ABL] Forum Post: CONTAINS - Single v Multiple performance

[danielb]

I have a quick question regarding the CONTAINS operator. Is there any performance/efficiency benefits using the "&" operator inside the criteria, v multiple CONTAINS clauses on the same query? For example: FOR EACH table WHERE table.field CONTAINS "alpha & beta & gamma" : v FOR EACH table WHERE table.field CONTAINS "alpha" AND table.field CONTAINS "beta" AND table.field CONTAINS "gamma" : The xref shows that the latter uses multiple indexes (all the same index), whereas the former uses a single index. I've run some performance comparisons, and the timings are almost identical (+/- some statistical differences), so I'm comfortable that there is no material performance difference, but wanted to be certain. I have found that the order of the terms inside of the CONTAINS operator make a difference, so if the least common word is first, then the query executes much quicker than if the most common word was first. I remember seeing a community post/KB about this, but can't find it at the moment.

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