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| bio | website | |
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| location | ||
| age | ||
| visits | member for | 1 year, 3 months |
| seen | May 19 at 6:45 | |
| stats | profile views | 5 |
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Apr 2 |
revised |
Why is DROP DATABASE taking so long? (MySQL) added note about new answer that seems to be better than my own |
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Apr 2 |
accepted | Why is DROP DATABASE taking so long? (MySQL) |
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Apr 2 |
comment |
Why is DROP DATABASE taking so long? (MySQL) Thanks. Any reason why you use mysqladmin instead of mysql? It seems like you have to type "mysqladmin" in front of every command. That would get tedious fast. |
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Mar 28 |
comment |
Why is DROP DATABASE taking so long? (MySQL) is mysqladmin a standard api? I have never used it. I usually use mysql command line or phpmyadmin. |
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Jan 13 |
revised |
Subqueries run very fast individually, but when joined are very slow improved title |
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Jan 13 |
comment |
Subqueries run very fast individually, but when joined are very slow I tried original query after adding composite indexes but did not see any difference. All the individual columns were indexed. Composite indexes did not make a noticeable difference. I don't think the problem was in the number of joins, but in the subqueries. It seems like MySQL is unable to use indexes in subqueries. 300 seconds vs. 3 milliseconds is an incredible difference in efficiency. I don't think I will have a problem doing 20-30 joins in this way with 100's of thousands of rows (and soon I will be). |
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Jan 12 |
comment |
Subqueries run very fast individually, but when joined are very slow Thanks! I just ran a test with 7 JOINs and it ran in 0.0318s. I imagine 7 would have taken a few years. So that is quite an improvement. I'm still surprised MySQL was not able to to speed up my original query, but this solution is much more elegant anyway. |
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Jan 12 |
accepted | Subqueries run very fast individually, but when joined are very slow |
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Jan 12 |
revised |
Subqueries run very fast individually, but when joined are very slow added complete solution |
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Jan 12 |
revised |
Why is DROP DATABASE taking so long? (MySQL) added another way to find and kill a mysql process |
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Jan 12 |
comment |
Subqueries run very fast individually, but when joined are very slow Thanks, that is working quite well with the numeric tables. I will test it with varchar tomorrow and hopefully it will work. But 0.0002s for 3 decimal joins is quite a promising start! |
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Jan 12 |
revised |
Subqueries run very fast individually, but when joined are very slow added table definitions |
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Jan 12 |
comment |
Subqueries run very fast individually, but when joined are very slow @ypercube yes the query looks rather complex. I do have individual indexes on attribute_id and value, but not composite. Do you think that would help? |
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Jan 12 |
revised |
Subqueries run very fast individually, but when joined are very slow added explanation of query and part of query. |
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Jan 12 |
comment |
Subqueries run very fast individually, but when joined are very slow MySQL supposedly does crate temporary tables during query execution. But whatever it's doing, it's doing it wrong (or I am). |
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Jan 12 |
revised |
Subqueries run very fast individually, but when joined are very slow added test using temporary tables resulted in very fast query |
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Jan 12 |
revised |
Subqueries run very fast individually, but when joined are very slow added 136 characters in body |
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Jan 12 |
asked | Subqueries run very fast individually, but when joined are very slow |
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Jan 11 |
revised |
MySQL collate error occurs when sent by PHP app but does not occur in phpMyAdmin improved title |
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Jan 11 |
answered | MySQL collate error occurs when sent by PHP app but does not occur in phpMyAdmin |
