


MySQL Trigger: Delete from "patron_info" After Deleting from "patrons"
To establish a trigger that automatically deletes rows from the "patron_info" table when corresponding rows are removed from the "patrons" table:
Syntax Error Correction:
The original trigger syntax error stems from attempting to use both "patrons.id" and "old.id" in the "WHERE" clause. To correctly delete rows from "patron_info" based on the deleted "patron" ID, the trigger should use "old.id":
<code class="sql">CREATE TRIGGER log_patron_delete AFTER DELETE on patrons FOR EACH ROW BEGIN DELETE FROM patron_info WHERE patron_info.pid = old.id; END</code>
Additional Considerations:
- Ensure a semicolon (";") terminates the DELETE statement within the trigger.
- Use delimiters when entering the trigger code through the console (e.g., "DELIMITER //").
The above is the detailed content of How to Fix a Syntax Error in MySQL Trigger: Deleting from \'patron_info\' After Deleting from \'patrons\'?. For more information, please follow other related articles on the PHP Chinese website!

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