The current SQL query that checks table existence is under optimized on big database #1439
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… optimized on big database
| break; | ||
| default: | ||
| // the MySQL-style LIMIT clause | ||
| query = "SELECT count(*) from (SELECT 1 FROM " + tableName + " LIMIT 1) T"; |
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why not just: SELECT 1 FROM tableNAME LIMIT 1
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I'll answer myself: because if the table is empty it would not work, however if the table doesn't exist it would throw a SQL Exception
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Yes that's the expected behavior. If the table is empty or pre-filled it will return true, if the table doesn't exist an SQLException will be thrown, the exception will be caught to return false
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Testing |
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Pulled, thanks |
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Related issue https://issues.jboss.org/browse/ISPN-2454