---
{
    "title": "SHOW ALTER TABLE MATERIALIZED VIEW",
    "language": "en"
}
---

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## SHOW ALTER TABLE MATERIALIZED VIEW

### Name

SHOW ALTER TABLE MATERIALIZED VIEW

### Description

This command is used to view the execution of the Create Materialized View job submitted through the [CREATE-MATERIALIZED-VIEW](../../sql-manual/sql-reference/Data-Definition-Statements/Create/CREATE-MATERIALIZED-VIEW.md) statement.

> This statement is equivalent to `SHOW ALTER TABLE ROLLUP`;

```sql
SHOW ALTER TABLE MATERIALIZED VIEW
[FROM database]
[WHERE]
[ORDER BY]
[LIMIT OFFSET]
````

- database: View jobs under the specified database. If not specified, the current database is used.
- WHERE: You can filter the result column, currently only the following columns are supported:
  - TableName: Only equal value filtering is supported.
  - State: Only supports equivalent filtering.
  - Createtime/FinishTime: Support =, >=, <=, >, <, !=
- ORDER BY: The result set can be sorted by any column.
- LIMIT: Use ORDER BY to perform page-turning query.

Return result description:

```sql
mysql> show alter table materialized view\G
**************************** 1. row ******************** ******
          JobId: 11001
      TableName: tbl1
     CreateTime: 2020-12-23 10:41:00
     FinishTime: NULL
  BaseIndexName: tbl1
RollupIndexName: r1
       RollupId: 11002
  TransactionId: 5070
          State: WAITING_TXN
            Msg:
       Progress: NULL
        Timeout: 86400
1 row in set (0.00 sec)
````

- `JobId`: Job unique ID.

- `TableName`: base table name

- `CreateTime/FinishTime`: Job creation time and end time.

- `BaseIndexName/RollupIndexName`: Base table name and materialized view name.

- `RollupId`: The unique ID of the materialized view.

- `TransactionId`: See the description of the State field.

- `State`: job status.

  - PENDING: The job is in preparation.

  - WAITING_TXN:

    Before officially starting to generate materialized view data, it will wait for the current running import transaction on this table to complete. And the `TransactionId` field is the current waiting transaction ID. When all previous imports for this ID are complete, the job will actually start.

  - RUNNING: The job is running.

  - FINISHED: The job ran successfully.

  - CANCELLED: The job failed to run.

- `Msg`: error message

- `Progress`: job progress. The progress here means `completed tablets/total tablets`. Materialized views are created at tablet granularity.

- `Timeout`: Job timeout, in seconds.

### Example

1. View the materialized view jobs under the database example_db

   ```sql
   SHOW ALTER TABLE MATERIALIZED VIEW FROM example_db;
   ````

### Keywords

    SHOW, ALTER, TABLE, MATERIALIZED, VIEW

### Best Practice