Idle session timeout

When the idle period of the current session exceeds the specified threshold, the system automatically closes the current session. This topic describes the idle session timeout error and the troubleshooting procedure.

Error: ERROR-02013

Error message

ERROR-02013: Lost connection to MySQL server during query

Example

After the current session remains idle for a period longer than the specified threshold, this error is returned if you execute an SQL statement to query data in the t1 table.

obclient> SELECT * FROM t1;
ERROR-02013: Lost connection to MySQL server during query

Troubleshooting procedure

Method 1

Reconnect to the Oracle database.

1. Reconnect the SYS user.

   [admin@k08j13249.eu95sqa /home/admin]
   $obclient -h172.10.10.10 -P1000 -usys@Oracle -p -A
   Enter password:
   Welcome to the OceanBase.  Commands end with ; or \g.
   Your OceanBase connection id is 3221583828
   Server version: OceanBase 3.2.4.0 (r100000072022102819-2a28da9e758e2d232c41fa1a1b0070a08b77dd7d) (Built Oct 28 2022 19:46:38)
   
   Copyright (c) 2000, 2018, OceanBase Corporation Ab and others.
   
   Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
   

2. Query data in the t1 table again.

   obclient> SELECT * FROM t1;
   +----+------+-------+------------------------------+
   | ID | NAME | VALUE | GMT_CREATE                   |
   +----+------+-------+------------------------------+
   |  1 | CN   |  NULL | 12-MAY-22 11.29.49.782106 AM |
   |  2 | UK   |  NULL | 12-MAY-22 11.29.49.782106 AM |
   |  3 | US   |  NULL | 12-MAY-22 11.29.49.782106 AM |
   +----+------+-------+------------------------------+
   3 rows in set
   

Method 2

Modify session timeout parameters.

1. Query the wait_timeout variable in the variables view.

   obclient> SHOW variables WHERE VARIABLE_NAME = 'wait_timeout';
   +---------------+-------+
   | VARIABLE_NAME | VALUE |
   +---------------+-------+
   | wait_timeout  | 10    |
   +---------------+-------+
   1 row in set
   

2. Set the wait_timeout parameter to 28800.

   Note

   This parameter specifies the time in seconds that the server waits for an interactive idle connection to become active before closing it.

   obclient> SET wait_timeout = 28800;
   Query OK, 0 rows affected
   

3. Set the interactive_timeout parameter to 28800.

   Note

   This parameter specifies the time in seconds that the server waits for a non-interactive idle connection to become active before the server closes the connection.

   obclient> SET interactive_timeout = 28800;
   Query OK, 0 rows affected
   

4. Query data in the t1 table again.

   obclient> SELECT * FROM t1;
   +----+------+-------+------------------------------+
   | ID | NAME | VALUE | GMT_CREATE                   |
   +----+------+-------+------------------------------+
   |  1 | CN   |  NULL | 12-MAY-22 11.29.49.782106 AM |
   |  2 | UK   |  NULL | 12-MAY-22 11.29.49.782106 AM |
   |  3 | US   |  NULL | 12-MAY-22 11.29.49.782106 AM |
   +----+------+-------+------------------------------+
   3 rows in set