Registers a trigger on a table.
CREATE TRIGGER trigger_name ON table_name USING 'java_class'
- Uppercase means literal
- Lowercase means not literal
- Italics mean optional
- The pipe (|) symbol means OR or AND/OR
- Ellipsis (...) means repeatable
- Orange ( and ) means not literal, indicates scope
A semicolon that terminates CQL statements is not included in the synopsis.
CREATE TRIGGER myTrigger ON myTable USING 'org.apache.cassandra.triggers.InvertedIndex'
The actual logic that makes up the trigger can be written in any Java (JVM) language and exists outside the database. The Java class in this example that implements the trigger is named org.apache.cassandra.triggers and defined in an Apache repository. You place the trigger code in a lib/triggers subdirectory of the Cassandra installation directory, it loads during cluster startup, and exists on every node that participates in a cluster. The trigger defined on a table fires before a requested DML statement occurs, which ensures the atomicity of the transaction.