Triggering Actions on SELECT Statements in MySQL
Can triggers be used to initiate actions when a SELECT statement is executed on a given table?
Answer:
No, MySQL triggers are designed to respond specifically to INSERT, UPDATE, or DELETE operations. They cannot be invoked by SELECT statements.
Alternative Solution:
To achieve the desired functionality, where an INSERT statement is executed on table X after selecting any record from table Y, a more indirect approach is required.
-
Create Stored Procedures:
- Develop stored procedures that execute the desired SELECTs on table X.
-
Restrict Direct SELECT Access:
- Modify user privileges to restrict direct SELECT access to table X and force users to use the stored procedures instead.
-
Modify Stored Procedures:
- Enhance the stored procedures to include a call to an additional stored procedure responsible for performing the intended action (e.g., INSERT) when triggered.
By implementing this solution, the desired behavior of triggering actions on select statements can be achieved.
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