How to Fix the \'Commands Out of Sync\' Error in Python When Using MySQL Stored Procedures?

Resolving "Commands Out of Sync" Error in Python When Interfacing with Stored Procedures in MySQL

In Python, while utilizing Django to execute stored procedures in MySQL, a common error encountered is "commands out of sync; you can't run this command now." This error arises when attempting to execute a second statement following the procedure call, with the transaction still ongoing.

To resolve this issue, it is crucial to close the cursor used for executing the procedure and create a new one before executing subsequent statements:

cursor.close()

cursor = connection.cursor()

The cursor can be closed immediately after fetching the results from the procedure call. The result set is unaffected and can still be accessed.

Consider a simplified MySQL procedure as an example:

delimiter $$
create procedure my_mysql_procedure(p_page_id int)
begin

        select 1
        from dual; 

    end$$
delimiter ;

Within Python, the error "commands out of sync" would occur when attempting to execute another statement after calling the procedure, as seen in this code:

cursor.callproc('my_mysql_procedure', [some_id,]) 
result = cursor.fetchall()
for r in result:
    do something

cursor.execute("select * from some_table")
result = cursor.fetchall()

By closing and re-opening the cursor after the procedure call, the error is eliminated, and subsequent statements can be executed without issue. This solution ensures that MySQL maintains the correct command sequence and allows for seamless execution of subsequent database operations.

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