ALTER TABLE¶
ALTER TABLE can be used to make schema changes to a table. It works in conjunction with several subcommands.
Locks¶
Schema changes take an exclusive lock on tables. While these operations are usually short, other statements may have to wait until the schema changes are completed.
Subcommands¶
| Command | Usage |
|---|---|
| ADD COLUMN | Add a new column to a table |
| DROP COLUMN | Drop a column from a table |
| RENAME COLUMN | Rename a column |
| RENAME TABLE | Rename a table |
| CLUSTER BY | Modify (add or reorder) the clustering keys in a table |
| DROP CLUSTERING KEY<drop_clustering_key | Drop all clustering keys |