I tried writing query using exists
, but no success so开发者_运维技巧 far. Searching hasn't helped so far.
If you attempt to alter a table that does not exist, the query will fail with an error: Table 'database.table' doesn't exist
MySQL does support ALTER IGNORE TABLE
, but that only turns errors into warnings if you're attempting to create a unique index while there are values in the table that violate that index.
If you would like to make sure that you do not produce any database queries, I would suggest ensuring the table's existence using SHOW TABLES LIKE 'tablename'
before running your ALTER TABLE
query.
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