This documentation is for an unreleased version of Apache Flink Table Store. We recommend you use the latest stable version.
Altering Tables
Altering Tables #
Changing/Adding Table Properties #
The following SQL sets write-buffer-size
table property to 256 MB
.
ALTER TABLE my_table SET (
'write-buffer-size' = '256 MB'
);
ALTER TABLE my_table SET TBLPROPERTIES (
'write-buffer-size' = '256 MB'
);
Removing Table Properties #
The following SQL removes write-buffer-size
table property.
ALTER TABLE my_table RESET ('write-buffer-size');
ALTER TABLE my_table UNSET TBLPROPERTIES ('write-buffer-size');
Adding New Columns #
The following SQL adds two columns c1
and c2
to table my_table
.
ALTER TABLE my_table ADD COLUMNS (
c1 INT,
c2 STRING
);
Renaming Column Name #
The following SQL renames column c0
in table my_table
to c1
.
ALTER TABLE my_table RENAME COLUMN c0 TO c1;
Dropping Columns #
The syntax is:
ALTER TABLE table_identifier DROP { COLUMN | COLUMNS } [(] col_name [, ... ] [)]
The following SQL drops tow columns c1
and c2
from table my_table
.
ALTER TABLE my_table DROP COLUMNS (c1, c2);
Changing Column Nullability #
The following SQL sets column coupon_info
to be nullable.
ALTER TABLE my_table ALTER COLUMN coupon_info DROP NOT NULL;
Changing Column Comment #
The following SQL changes comment of column buy_count
to buy count
.
ALTER TABLE my_table ALTER COLUMN buy_count COMMENT 'buy count';