spark-instrumented-optimizer/docs/sql-ref-syntax-ddl-repair-table.md
Huaxin Gao a75dc80a76 [SPARK-31636][SQL][DOCS] Remove HTML syntax in SQL reference
### What changes were proposed in this pull request?
Remove the unneeded embedded inline HTML markup by using the basic markdown syntax.
Please see #28414

### Why are the changes needed?
Make the doc cleaner and easily editable by MD editors.

### Does this PR introduce _any_ user-facing change?
No

### How was this patch tested?
Manually build and check

Closes #28451 from huaxingao/html_cleanup.

Authored-by: Huaxin Gao <huaxing@us.ibm.com>
Signed-off-by: Sean Owen <srowen@gmail.com>
2020-05-10 12:57:25 -05:00

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---
layout: global
title: REPAIR TABLE
displayTitle: REPAIR TABLE
license: |
Licensed to the Apache Software Foundation (ASF) under one or more
contributor license agreements. See the NOTICE file distributed with
this work for additional information regarding copyright ownership.
The ASF licenses this file to You under the Apache License, Version 2.0
(the "License"); you may not use this file except in compliance with
the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
---
### Description
`MSCK REPAIR TABLE` recovers all the partitions in the directory of a table and updates the Hive metastore. When creating a table using `PARTITIONED BY` clause, partitions are generated and registered in the Hive metastore. However, if the partitioned table is created from existing data, partitions are not registered automatically in the Hive metastore. User needs to run `MSCK REPAIR TABLE` to register the partitions. `MSCK REPAIR TABLE` on a non-existent table or a table without partitions throws an exception. Another way to recover partitions is to use `ALTER TABLE RECOVER PARTITIONS`.
### Syntax
```sql
MSCK REPAIR TABLE table_identifier
```
### Parameters
* **table_identifier**
Specifies the name of the table to be repaired. The table name may be optionally qualified with a database name.
**Syntax:** `[ database_name. ] table_name`
### Examples
```sql
-- create a partitioned table from existing data /tmp/namesAndAges.parquet
CREATE TABLE t1 (name STRING, age INT) USING parquet PARTITIONED BY (age)
LOCATION "/tmp/namesAndAges.parquet";
-- SELECT * FROM t1 does not return results
SELECT * FROM t1;
-- run MSCK REPAIR TABLE to recovers all the partitions
MSCK REPAIR TABLE t1;
-- SELECT * FROM t1 returns results
SELECT * FROM t1;
+-------+---+
| name|age|
+-------+---+
|Michael| 20|
+-------+---+
| Justin| 19|
+-------+---+
| Andy| 30|
+-------+---+
```
### Related Statements
* [ALTER TABLE](sql-ref-syntax-ddl-alter-table.html)