ADMIN SHOW DDL [JOBS|JOB QUERIES]
ADMIN SHOW DDL [JOBS|JOB QUERIES] 语句显示了正在运行和最近完成的 DDL 作业的信息。
语法图
- AdminStmt
- NumList
- WhereClauseOptional
AdminStmt ::=
'ADMIN' ( 'SHOW' ( 'DDL' ( 'JOBS' Int64Num? WhereClauseOptional | 'JOB' 'QUERIES' NumList )? | TableName 'NEXT_ROW_ID' | 'SLOW' AdminShowSlow ) | 'CHECK' ( 'TABLE' TableNameList | 'INDEX' TableName Identifier ( HandleRange ( ',' HandleRange )* )? ) | 'RECOVER' 'INDEX' TableName Identifier | 'CLEANUP' ( 'INDEX' TableName Identifier | 'TABLE' 'LOCK' TableNameList ) | 'CHECKSUM' 'TABLE' TableNameList | 'CANCEL' 'DDL' 'JOBS' NumList | 'RELOAD' ( 'EXPR_PUSHDOWN_BLACKLIST' | 'OPT_RULE_BLACKLIST' | 'BINDINGS' ) | 'PLUGINS' ( 'ENABLE' | 'DISABLE' ) PluginNameList | 'REPAIR' 'TABLE' TableName CreateTableStmt | ( 'FLUSH' | 'CAPTURE' | 'EVOLVE' ) 'BINDINGS' )
NumList ::=
Int64Num ( ',' Int64Num )*
WhereClauseOptional ::=
WhereClause?
示例
ADMIN SHOW DDL
可以通过 ADMIN SHOW DDL 语句查看当前正在运行的 DDL 作业：
ADMIN SHOW DDL;
ADMIN SHOW DDL;
+------------+--------------------------------------+---------------+--------------+--------------------------------------+-------+
| SCHEMA_VER | OWNER_ID | OWNER_ADDRESS | RUNNING_JOBS | SELF_ID | QUERY |
+------------+--------------------------------------+---------------+--------------+--------------------------------------+-------+
| 26 | 2d1982af-fa63-43ad-a3d5-73710683cc63 | 0.0.0.0:4000 | | 2d1982af-fa63-43ad-a3d5-73710683cc63 | |
+------------+--------------------------------------+---------------+--------------+--------------------------------------+-------+
1 row in set (0.00 sec)
ADMIN SHOW DDL JOBS
ADMIN SHOW DDL JOBS 语句用于查看当前 DDL 作业队列中的所有结果（包括正在运行以及等待运行的任务）以及已执行完成的 DDL 作业队列中的最近十条结果。
ADMIN SHOW DDL JOBS;
ADMIN SHOW DDL JOBS;
+--------+---------+--------------------+--------------+----------------------+-----------+----------+-----------+---------------------+---------------------+---------+
| JOB_ID | DB_NAME | TABLE_NAME | JOB_TYPE | SCHEMA_STATE | SCHEMA_ID | TABLE_ID | ROW_COUNT | START_TIME | END_TIME | STATE |
+--------+---------+--------------------+--------------+----------------------+-----------+----------+-----------+---------------------+---------------------+---------+
| 59 | test | t1 | add index | write reorganization | 1 | 55 | 88576 | 2020-08-17 07:51:58 | NULL | running |
| 60 | test | t2 | add index | none | 1 | 57 | 0 | 2020-08-17 07:51:59 | NULL | none |
| 58 | test | t2 | create table | public | 1 | 57 | 0 | 2020-08-17 07:41:28 | 2020-08-17 07:41:28 | synced |
| 56 | test | t1 | create table | public | 1 | 55 | 0 | 2020-08-17 07:41:02 | 2020-08-17 07:41:02 | synced |
| 54 | test | t1 | drop table | none | 1 | 50 | 0 | 2020-08-17 07:41:02 | 2020-08-17 07:41:02 | synced |
| 53 | test | t1 | drop index | none | 1 | 50 | 0 | 2020-08-17 07:35:44 | 2020-08-17 07:35:44 | synced |
| 52 | test | t1 | add index | public | 1 | 50 | 451010 | 2020-08-17 07:34:43 | 2020-08-17 07:35:16 | synced |
| 51 | test | t1 | create table | public | 1 | 50 | 0 | 2020-08-17 07:34:02 | 2020-08-17 07:34:02 | synced |
| 49 | test | t1 | drop table | none | 1 | 47 | 0 | 2020-08-17 07:34:02 | 2020-08-17 07:34:02 | synced |
| 48 | test | t1 | create table | public | 1 | 47 | 0 | 2020-08-17 07:33:37 | 2020-08-17 07:33:37 | synced |
| 46 | mysql | stats_extended | create table | public | 3 | 45 | 0 | 2020-08-17 06:42:38 | 2020-08-17 06:42:38 | synced |
| 44 | mysql | opt_rule_blacklist | create table | public | 3 | 43 | 0 | 2020-08-17 06:42:38 | 2020-08-17 06:42:38 | synced |
+--------+---------+--------------------+--------------+----------------------+-----------+----------+-----------+---------------------+---------------------+---------+
12 rows in set (0.00 sec)
由上述 ADMIN 查询结果可知：
job_id为 59 的 DDL 作业当前正在进行中（STATE列显示为running）。SCHEMA_STATE列显示了表当前处于write reorganization状态，一旦任务完成，将更改为public，以便用户会话可以公开观察到状态变更。end_time列显示为NULL，表明当前作业的完成时间未知。job_id为 60 的JOB_TYPE显示为add index，表明正在排队等待job_id为 59 的作业完成。当作业 59 完成时，作业 60 的STATE将更改为running。对于破坏性的更改（例如删除索引或删除表），当作业完成时，
SCHEMA_STATE将变为none。对于附加更改，SCHEMA_STATE将变为public。
若要限制表中显示的行数，可以指定 NUM 和 WHERE 条件：
ADMIN SHOW DDL JOBS [NUM] [WHERE where_condition];
NUM：用于查看已经执行完成的 DDL 作业队列中最近NUM条结果；未指定时，默认值为 10。WHERE：WHERE子句，用于添加过滤条件。
ADMIN SHOW DDL JOB QUERIES
ADMIN SHOW DDL JOB QUERIES 语句用于查看 job_id 对应的 DDL 任务的原始 SQL 语句：
ADMIN SHOW DDL JOBS;
ADMIN SHOW DDL JOB QUERIES 51;
ADMIN SHOW DDL JOB QUERIES 51;
+--------------------------------------------------------------+
| QUERY |
+--------------------------------------------------------------+
| CREATE TABLE t1 (id INT NOT NULL PRIMARY KEY auto_increment) |
+--------------------------------------------------------------+
1 row in set (0.02 sec)
只能在 DDL 历史作业队列中最近十条结果中搜索与 job_id 对应的正在运行中的 DDL 作业。
MySQL 兼容性
ADMIN SHOW DDL [JOBS|JOB QUERIES] 语句是 TiDB 对 MySQL 语法的扩展。