layout: global title: ALTER TABLE displayTitle: ALTER 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
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ALTER TABLE
statement changes the schema or properties of a table.
ALTER TABLE RENAME TO
statement changes the table name of an existing table in the database. The table rename command cannot be used to move a table between databases, only to rename a table within the same database.
If the table is cached, the commands clear cached data of the table. The cache will be lazily filled when the next time the table is accessed. Additionally:
ALTER TABLE table_identifier RENAME TO table_identifier ALTER TABLE table_identifier partition_spec RENAME TO partition_spec
table_identifier
Specifies a table name, which may be optionally qualified with a database name.
Syntax: [ database_name. ] table_name
partition_spec
Partition to be renamed. Note that one can use a typed literal (e.g., date‘2019-01-02’) in the partition spec.
Syntax: PARTITION ( partition_col_name = partition_col_val [ , ... ] )
ALTER TABLE ADD COLUMNS
statement adds mentioned columns to an existing table.
ALTER TABLE table_identifier ADD COLUMNS ( col_spec [ , ... ] )
table_identifier
Specifies a table name, which may be optionally qualified with a database name.
Syntax: [ database_name. ] table_name
COLUMNS ( col_spec )
Specifies the columns to be added.
ALTER TABLE ALTER COLUMN
or ALTER TABLE CHANGE COLUMN
statement changes column's definition.
ALTER TABLE table_identifier { ALTER | CHANGE } [ COLUMN ] col_spec alterColumnAction
table_identifier
Specifies a table name, which may be optionally qualified with a database name.
Syntax: [ database_name. ] table_name
COLUMNS ( col_spec )
Specifies the column to be altered or be changed.
alterColumnAction
Change column's definition.
ALTER TABLE ADD
statement adds partition to the partitioned table.
If the table is cached, the command clears cached data of the table and all its dependents that refer to it. The cache will be lazily filled when the next time the table or the dependents are accessed.
ALTER TABLE table_identifier ADD [IF NOT EXISTS] ( partition_spec [ partition_spec ... ] )
table_identifier
Specifies a table name, which may be optionally qualified with a database name.
Syntax: [ database_name. ] table_name
partition_spec
Partition to be added. Note that one can use a typed literal (e.g., date‘2019-01-02’) in the partition spec.
Syntax: PARTITION ( partition_col_name = partition_col_val [ , ... ] )
ALTER TABLE DROP
statement drops the partition of the table.
If the table is cached, the command clears cached data of the table and all its dependents that refer to it. The cache will be lazily filled when the next time the table or the dependents are accessed.
ALTER TABLE table_identifier DROP [ IF EXISTS ] partition_spec [PURGE]
table_identifier
Specifies a table name, which may be optionally qualified with a database name.
Syntax: [ database_name. ] table_name
partition_spec
Partition to be dropped. Note that one can use a typed literal (e.g., date‘2019-01-02’) in the partition spec.
Syntax: PARTITION ( partition_col_name = partition_col_val [ , ... ] )
ALTER TABLE SET
command is used for setting the table properties. If a particular property was already set, this overrides the old value with the new one.
ALTER TABLE UNSET
is used to drop the table property.
-- Set Table Properties ALTER TABLE table_identifier SET TBLPROPERTIES ( key1 = val1, key2 = val2, ... ) -- Unset Table Properties ALTER TABLE table_identifier UNSET TBLPROPERTIES [ IF EXISTS ] ( key1, key2, ... )
ALTER TABLE SET
command is used for setting the SERDE or SERDE properties in Hive tables. If a particular property was already set, this overrides the old value with the new one.
-- Set SERDE Properties ALTER TABLE table_identifier [ partition_spec ] SET SERDEPROPERTIES ( key1 = val1, key2 = val2, ... ) ALTER TABLE table_identifier [ partition_spec ] SET SERDE serde_class_name [ WITH SERDEPROPERTIES ( key1 = val1, key2 = val2, ... ) ]
ALTER TABLE SET
command can also be used for changing the file location and file format for existing tables.
If the table is cached, the ALTER TABLE .. SET LOCATION
command clears cached data of the table and all its dependents that refer to it. The cache will be lazily filled when the next time the table or the dependents are accessed.
-- Changing File Format ALTER TABLE table_identifier [ partition_spec ] SET FILEFORMAT file_format -- Changing File Location ALTER TABLE table_identifier [ partition_spec ] SET LOCATION 'new_location'
table_identifier
Specifies a table name, which may be optionally qualified with a database name.
Syntax: [ database_name. ] table_name
partition_spec
Specifies the partition on which the property has to be set. Note that one can use a typed literal (e.g., date‘2019-01-02’) in the partition spec.
Syntax: PARTITION ( partition_col_name = partition_col_val [ , ... ] )
SERDEPROPERTIES ( key1 = val1, key2 = val2, ... )
Specifies the SERDE properties to be set.
-- RENAME table DESC student; +-----------------------+---------+-------+ | col_name|data_type|comment| +-----------------------+---------+-------+ | name| string| NULL| | rollno| int| NULL| | age| int| NULL| |# Partition Information| | | | # col_name|data_type|comment| | age| int| NULL| +-----------------------+---------+-------+ ALTER TABLE Student RENAME TO StudentInfo; -- After Renaming the table DESC StudentInfo; +-----------------------+---------+-------+ | col_name|data_type|comment| +-----------------------+---------+-------+ | name| string| NULL| | rollno| int| NULL| | age| int| NULL| |# Partition Information| | | | # col_name|data_type|comment| | age| int| NULL| +-----------------------+---------+-------+ -- RENAME partition SHOW PARTITIONS StudentInfo; +---------+ |partition| +---------+ | age=10| | age=11| | age=12| +---------+ ALTER TABLE default.StudentInfo PARTITION (age='10') RENAME TO PARTITION (age='15'); -- After renaming Partition SHOW PARTITIONS StudentInfo; +---------+ |partition| +---------+ | age=11| | age=12| | age=15| +---------+ -- Add new columns to a table DESC StudentInfo; +-----------------------+---------+-------+ | col_name|data_type|comment| +-----------------------+---------+-------+ | name| string| NULL| | rollno| int| NULL| | age| int| NULL| |# Partition Information| | | | # col_name|data_type|comment| | age| int| NULL| +-----------------------+---------+-------+ ALTER TABLE StudentInfo ADD columns (LastName string, DOB timestamp); -- After Adding New columns to the table DESC StudentInfo; +-----------------------+---------+-------+ | col_name|data_type|comment| +-----------------------+---------+-------+ | name| string| NULL| | rollno| int| NULL| | LastName| string| NULL| | DOB|timestamp| NULL| | age| int| NULL| |# Partition Information| | | | # col_name|data_type|comment| | age| int| NULL| +-----------------------+---------+-------+ -- Add a new partition to a table SHOW PARTITIONS StudentInfo; +---------+ |partition| +---------+ | age=11| | age=12| | age=15| +---------+ ALTER TABLE StudentInfo ADD IF NOT EXISTS PARTITION (age=18); -- After adding a new partition to the table SHOW PARTITIONS StudentInfo; +---------+ |partition| +---------+ | age=11| | age=12| | age=15| | age=18| +---------+ -- Drop a partition from the table SHOW PARTITIONS StudentInfo; +---------+ |partition| +---------+ | age=11| | age=12| | age=15| | age=18| +---------+ ALTER TABLE StudentInfo DROP IF EXISTS PARTITION (age=18); -- After dropping the partition of the table SHOW PARTITIONS StudentInfo; +---------+ |partition| +---------+ | age=11| | age=12| | age=15| +---------+ -- Adding multiple partitions to the table SHOW PARTITIONS StudentInfo; +---------+ |partition| +---------+ | age=11| | age=12| | age=15| +---------+ ALTER TABLE StudentInfo ADD IF NOT EXISTS PARTITION (age=18) PARTITION (age=20); -- After adding multiple partitions to the table SHOW PARTITIONS StudentInfo; +---------+ |partition| +---------+ | age=11| | age=12| | age=15| | age=18| | age=20| +---------+ -- ALTER OR CHANGE COLUMNS DESC StudentInfo; +-----------------------+---------+-------+ | col_name|data_type|comment| +-----------------------+---------+-------+ | name| string| NULL| | rollno| int| NULL| | LastName| string| NULL| | DOB|timestamp| NULL| | age| int| NULL| |# Partition Information| | | | # col_name|data_type|comment| | age| int| NULL| +-----------------------+---------+-------+ ALTER TABLE StudentInfo ALTER COLUMN name COMMENT "new comment"; --After ALTER or CHANGE COLUMNS DESC StudentInfo; +-----------------------+---------+-----------+ | col_name|data_type| comment| +-----------------------+---------+-----------+ | name| string|new comment| | rollno| int| NULL| | LastName| string| NULL| | DOB|timestamp| NULL| | age| int| NULL| |# Partition Information| | | | # col_name|data_type| comment| | age| int| NULL| +-----------------------+---------+-----------+ -- Change the fileformat ALTER TABLE loc_orc SET fileformat orc; ALTER TABLE p1 partition (month=2, day=2) SET fileformat parquet; -- Change the file Location ALTER TABLE dbx.tab1 PARTITION (a='1', b='2') SET LOCATION '/path/to/part/ways' -- SET SERDE/ SERDE Properties ALTER TABLE test_tab SET SERDE 'org.apache.hadoop.hive.serde2.columnar.LazyBinaryColumnarSerDe'; ALTER TABLE dbx.tab1 SET SERDE 'org.apache.hadoop' WITH SERDEPROPERTIES ('k' = 'v', 'kay' = 'vee') -- SET TABLE PROPERTIES ALTER TABLE dbx.tab1 SET TBLPROPERTIES ('winner' = 'loser'); -- SET TABLE COMMENT Using SET PROPERTIES ALTER TABLE dbx.tab1 SET TBLPROPERTIES ('comment' = 'A table comment.'); -- Alter TABLE COMMENT Using SET PROPERTIES ALTER TABLE dbx.tab1 SET TBLPROPERTIES ('comment' = 'This is a new comment.'); -- DROP TABLE PROPERTIES ALTER TABLE dbx.tab1 UNSET TBLPROPERTIES ('winner');