Oracle Data Definition Language (DDL)

General Information
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DDL Statements
Lock Timeout DDL_LOCK_TIMEOUT(<number_of_seconds>);
conn / as sysdba

set linesize 121
col name format a30
col value format a30

SELECT name, value
FROM gv$parameter
WHERE name LIKE 'ddl_lock%';

-- range is 0 (the default) to 100,000
ALTER SYSTEM SET ddl_lock_timeout=20;
-- or
ALTER SESSION SET ddl_lock_timeout=20;
Lock Timeout Demo conn uwclass/uwclass@pdbdev

SELECT table_name, tablespace_name
FROM user_tables;

Step Session 1 Session 2
1 conn uwclass/uwclass@pdbdev conn uwclass/uwclass@pdbdev
2 desc test1

SELECT * FROM test1;
desc test1

SELECT * FROM test1;
3 LOCK TABLE test1
IN exclusive MODE nowait;
RENAME test1 TO test2;
4 COMMIT; RENAME test1 TO test2;
5   ALTER SYSTEM SET ddl_lock_timeout=60;

SELECT name, value
FROM gv$parameter
WHERE name LIKE 'ddl_lock%';
6 LOCK TABLE test2
IN exclusive MODE nowait;
RENAME test2 TO test3;

ALTER SYSTEM SET ddl_lock_timeout=0;

SELECT name, value
FROM gv$parameter
WHERE name LIKE 'ddl_lock%';

Related Topics
DCL Statements
DDL Event Triggers
DML Statements
What's New In 12cR1
What's New In 12cR2

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