Dm8: Dameng database - lock timeout

DM8: Daydream database - Lock timeout

1、 Sometimes, the database operation will encounter lock timeout

1.1 Find the session that caused the block , Commit or roll back transactions , Unblock .
1.2 Close blocked session

SP_CLOSE_SESSION(SESS_ID)

2、 adopt sql Statement to query transactions related to lock timeout / conversation

SELECT
        T1.T1_SESS_ID,T1.T1_SQL_TEXT,T1.T1_TRX_ID,
        T2.T2_TW_ID,T2_SQL_TEXT,T2_SESS_ID
FROM
        (
                SELECT
                        SESS.SESS_ID T1_SESS_ID  ,
                        SESS.SQL_TEXT T1_SQL_TEXT,
                        TW.ID T1_TRX_ID          ,
                        TW.WAIT_FOR_ID T1_TW_ID
                FROM
                        V$TRXWAIT TW,
                        V$SESSIONS SESS
                WHERE
                        TW.ID=SESS.TRX_ID
        )
        T1,
        (
                SELECT
                        SESS.SESS_ID T2_SESS_ID  ,
                        SESS.SQL_TEXT T2_SQL_TEXT,
                        TW.WAIT_FOR_ID T2_TW_ID
                FROM
                        V$TRXWAIT TW,
                        V$SESSIONS SESS
                WHERE
                        TW.WAIT_FOR_ID=SESS.TRX_ID
        )
        T2
WHERE
        T1.T1_TW_ID=T2.T2_TW_ID

3、 The query results are shown in the figure ：

4、 The results specify ：

4.1 Display transaction waiting information .

SELECT * FROM V$TRXWAIT;

order Number	Column	data type	explain
1	ID	BIGINT	Business ID
2	WAIT_FOR_ID	BIGINT	The transaction waiting ID
3	WAIT_TIME	INTEGER	Current waiting time

4.2 Show session specific information , If implemented sql sentence 、 Main database name 、 Current session state 、 User name and so on .

SELECT * FROM V$SESSIONS;

4.3 Display active transaction lock information .
SELECT * FROM V$LOCK;;