MySQL & Python- Error: 2006 mysql has gone away

MySQL & Python: Error: 2006 mysql has gone away

This problem occurs for multiple reasons such as DB connection problem. In our code, we hit this issue due to a subtle problem with DB cursor.

The code was as following:

with conn as cur:
    try:
        print "hello"
    except:
        print "sorry"
    finally: 
        conn.close()

The above code would throw the error 2016 mysql has gone away exception. The problem lies in with conn as cur. This statement creates a cursor on the DB and the cursor object autmatically gets destroyed.
Here, we are closing the DB connection before the automatic destruction happened.

So since connection was invalid(closed), cursor deletion hit an exception.

The solution is to close the connection after cursor object deletion.

try:
    with conn as cur:
        print "hello"
except:
    print "sorry"
finally: 
    conn.close()

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