Lost connection to MySQL server during query using python,pymysql & SSHTunnel

Question

I'm using SSHTunnel to connect to Mysql. I'm planning to export all tables from the dataset to CSV. Here is the code

def OpenSSHTunnel():
    global server
    server = SSHTunnelForwarder(
        ('*.*.*.*', 22),  
        ssh_username="",  
        ssh_pkey="C:/Users/Administrator/Desktop/***",
        remote_bind_address=('*.*.*.*', 3306),
        local_bind_address=('0.0.0.0', 10022))

def exportToCsv(db):
    conn = pymysql.connect(host='127.0.0.1', 
                           port=10022,
                           user='**', 
                           passwd='**',
                           db=db)
    cur = conn.cursor()
    #cur.execute("set global max_allowed_packet=67108864")

    # RETRIEVE TABLES
    cur.execute("SHOW TABLES")
    tables = []
    for row in cur.fetchall():
        tables.append(row[0])

    for t in tables:    
        # SELECT STATEMENTS
        cur.execute("SELECT * FROM `{}`".format(t))
        tempcsv = '{}.csv'.format(t)
        rows = cur.fetchall()

        fp = open(tempcsv, 'w',newline='',encoding='utf-8')
        writer = csv.writer(fp)
        writer.writerow([i[0] for i in cur.description])   # COLUMN HEADERS
        writer.writerows(rows)
        fp.close()

I got the error "2013, 'Lost connection to MySQL server during query'" so is there a way to fix the problem?

I tried to set global max_allowed_packet, but the error "1227, 'Access denied; you need (at least one of) the SUPER privilege(s) for this operation'"

Answer 1

I couldn't tell you why, but I had this problem, and it's related to the SSH tunnel. For some reason, "returning" the tunnel/connection from a method and passing it around doesn't seem to work. I tried just doing everything inside the tunnel & connection in the main method, and that fixed it for me.