layout: global title: DESCRIBE TABLE displayTitle: DESCRIBE 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

DESCRIBE TABLE statement returns the basic metadata information of a table. The metadata information includes column name, column type and column comment. Optionally a partition spec or column name may be specified to return the metadata pertaining to a partition or column respectively.

Syntax

{% highlight sql %} { DESC | DESCRIBE } [ TABLE ] [ format ] table_identifier [ partition_spec ] [ col_name ] {% endhighlight %}

Parameters

<b>Syntax:</b>
  <code>
    [ database_name. ] [ table_name. ] column_name
  </code>

Examples

{% highlight sql %} -- Creates a table customer. Assumes current database is salesdb. CREATE TABLE customer( cust_id INT, state VARCHAR(20), name STRING COMMENT ‘Short name’ ) USING parquet PARTITION BY state; ;

-- Returns basic metadata information for unqualified table customer DESCRIBE TABLE customer; +-----------------------+---------+----------+ |col_name |data_type|comment | +-----------------------+---------+----------+ |cust_id |int |null | |name |string |Short name| |state |string |null | |# Partition Information| | | |# col_name |data_type|comment | |state |string |null | +-----------------------+---------+----------+

-- Returns basic metadata information for qualified table customer DESCRIBE TABLE salesdb.customer; +-----------------------+---------+----------+ |col_name |data_type|comment | +-----------------------+---------+----------+ |cust_id |int |null | |name |string |Short name| |state |string |null | |# Partition Information| | | |# col_name |data_type|comment | |state |string |null | +-----------------------+---------+----------+

-- Returns additional metadata such as parent database, owner, access time etc. DESCRIBE TABLE EXTENDED customer; +----------------------------+------------------------------+----------+ |col_name |data_type |comment | +----------------------------+------------------------------+----------+ |cust_id |int |null | |name |string |Short name| |state |string |null | |# Partition Information | | | |# col_name |data_type |comment | |state |string |null | | | | | |# Detailed Table Information| | | |Database |salesdb | | |Table |customer | | |Owner | | | |Created Time |Fri Aug 30 09:26:04 PDT 2019 | | |Last Access |Wed Dec 31 16:00:00 PST 1969 | | |Created By | | | |Type |MANAGED | | |Provider |parquet | | |Location |file:.../salesdb.db/customer | | |Serde Library |...serde.ParquetHiveSerDe | | |InputFormat |...MapredParquetInputFormat | | |OutputFormat |...MapredParquetOutputFormat | | +----------------------------+------------------------------+----------+

-- Returns partition metadata such as partitioning column name, column type and comment. DESCRIBE TABLE customer PARTITION (state = ‘AR’);

+--------------------------------+-----------------------------------------+----------+ |col_name |data_type |comment | +--------------------------------+-----------------------------------------+----------+ |cust_id |int |null | |name |string |Short name| |state |string |null | |# Partition Information | | | |# col_name |data_type |comment | |state |string |null | | | | | |# Detailed Partition Information| | | |Database |salesdb | | |Table |customer | | |Partition Values |[state=AR] | | |Location |file:.../salesdb.db/customer/state=AR | | |Serde Library |...serde.ParquetHiveSerDe | | |InputFormat |...parquet.MapredParquetInputFormat | | |OutputFormat |...parquet.MapredParquetOutputFormat | | |Storage Properties |[path=file:.../salesdb.db/customer, | | | | serialization.format=1] | | |Partition Parameters |{rawDataSize=-1, numFiles=1l, | | | | transient_lastDdlTime=1567185245, | | | | totalSize=688, | | | | COLUMN_STATS_ACCURATE=false, numRows=-1}| | |Created Time |Fri Aug 30 10:14:05 PDT 2019 | | |Last Access |Wed Dec 31 16:00:00 PST 1969 | | |Partition Statistics |688 bytes | | +--------------------------------+-----------------------------------------+----------+

-- Returns the metadata for name column. -- Optional TABLE clause is omitted and column is fully qualified. DESCRIBE customer salesdb.customer.name; +---------+----------+ |info_name|info_value| +---------+----------+ |col_name |name | |data_type|string | |comment |Short name| +---------+----------+ {% endhighlight %}

Related Statements