Delete multiple tables from a single query by separating from semicolon

匆匆过客 提交于 2019-12-01 09:08:04

问题


I am trying to delete multiple tables in a single operation from sqlite. I tried separating it by semicolon but it didn't work out as expected. Here is my current code :

NSString *query = @"DELETE from Friends;DELETE from Stream;DELETE from Version";

I need some guidance on what could the problem be here, or if I am missing something.


回答1:


To make an atomic operation out of multiple statements, use a transaction:

BEGIN;
DELETE FROM Friends;
DELETE FROM Stream;
DELETE FROM Version;
COMMIT;

You have to execute these five commands one by one if you're using sqlite3_prepare_v2; with sqlite3_exec, you can execute them with one call (but sqlite3_exec would not support SQL parameters).



来源:https://stackoverflow.com/questions/24547819/delete-multiple-tables-from-a-single-query-by-separating-from-semicolon

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