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43 | CONSTRAINT |
Manipulating Constraints
Constraints could be added or deleted using following syntax:
ALTER TABLE [db].name ADD CONSTRAINT constraint_name CHECK expression;
ALTER TABLE [db].name DROP CONSTRAINT constraint_name;
See more on constraints.
Queries will add or remove metadata about constraints from table so they are processed immediately.
:::warning Constraint check will not be executed on existing data if it was added. :::
All changes on replicated tables are broadcasted to ZooKeeper and will be applied on other replicas as well.