Timeline for EXPLAIN output suggests that my index is not being used
Current License: CC BY-SA 3.0
7 events
| when toggle format | what | by | license | comment | |
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| Nov 26, 2011 at 3:11 | history | migrated | from stackoverflow.com (revisions) | ||
| Nov 26, 2011 at 2:37 | comment | added | Adrian Cornish | In this case who cares what index the optimizer chooses? There is nothing wrong with the index itself, because the optimizer felt like it did not need it - what does it matter? | |
| Nov 26, 2011 at 2:21 | comment | added | Adrian Cornish | let us continue this discussion in chat | |
| Nov 26, 2011 at 2:15 | comment | added | Adrian Cornish | @ajreal: I am missing something in your points. The rows column of an explain has nothing to do with indexes right? Mysql choose not to use the index (maybe all the data is in a single page). Not sure I am understanding your point? Query optimization on a 5 row table is going to produce some 'odd' results because it pretty much does not matter how you optimize. | |
| Nov 26, 2011 at 2:10 | comment | added | Adrian Cornish | @ajreal It does not mean the index is broken though. Just the optimizer choose (in its mind) the most efficient way to query the data. I assumed the OP was expecting the rows column in the EXPLAIN to be exact. It does not mean the index is broken - just that mysql choose not to use it (probably). | |
| Nov 26, 2011 at 1:55 | comment | added | Adrian Cornish | So? Where did I say it does? What the optimizer chooses is up to it? The index still works. | |
| Nov 26, 2011 at 1:42 | history | answered | Adrian Cornish | CC BY-SA 3.0 |