ALTER TABLE Statement #
ALTER TABLE [IF EXISTS] [schema.]name ADD COLUMN name type [constraints]
ALTER TABLE [IF EXISTS] [schema.]name DROP COLUMN name
ALTER TABLE [IF EXISTS] [schema.]name RENAME TO [schema.]name
ALTER TABLE [IF EXISTS] [schema.]name SET IDENTITY TO value
ALTER TABLE [IF EXISTS] [schema.]name SET UNLOGGED;
ALTER TABLE [IF EXISTS] [schema.]name SET LOGGED;
ALTER TABLE [IF EXISTS] [schema.]name RENAME COLUMN name TO name
ALTER TABLE [IF EXISTS] [schema.]name SET COLUMN name DEFAULT const
ALTER TABLE [IF EXISTS] [schema.]name SET COLUMN name AS [(expr)] <IDENTITY | STORED | RESOLVED>
ALTER TABLE [IF EXISTS] [schema.]name UNSET COLUMN name AS <DEFAULT | IDENTITY | STORED | RESOLVED>
Change the definition of a table if it exists.
Currently, the ALTER TABLE operation cannot be part of multi-statement transactions.
Operations such as CREATE INDEX and ALTER TABLE ADD/DROP COLUMN are blocking but
completely parallel. Each backer worker will create an index for its partitions.
ALTER TABLE ADD/DROP COLUMN is a memory-expensive operation that requires at least double
the memory size of the original table to complete while the previous table is kept. To avoid this
operation repeating during WAL replay, it is recommended to run the CHECKPOINT operation right
after its completion.
Is recommended to organize tables by separating and creating volatile columns using JSON (to store objects or arrays).
create table example (device int primary key);
alter table example add column metrics json;