|CQL reference / CQL commands|
Define a new index on a single column of a table.
CREATE INDEX index_name ON keyspace_name.table_name ( column_name )
In the synopsis section of each statement, formatting has the following meaning:
A semicolon that terminates CQL statements is not included in the synopsis.
CREATE INDEX creates a new index on the given table for the named column. Optionally, specify a name for the index itself before the ON keyword. Enclose a single column name in parentheses. It is not necessary for the column to exist on any current rows. The column and its data type must be specified when the table is created, or added afterward by altering the table.
If data already exists for the column, Cassandra indexes the data during the execution of this statement. After the index is created, Cassandra indexes new data for the column automatically when new data is inserted.
In this release, Cassandra supports creating an index on a table having a compound primary key. You cannot create an index on the primary key itself. Cassandra does not support indexes on collections.
Define a table and then create an index on two of its named columns:
CREATE TABLE myschema.users ( userID uuid, fname text, lname text, email text, address text, zip int, state text, PRIMARY KEY (userID) ); CREATE INDEX user_state ON myschema.users (state); CREATE INDEX ON myschema.users (zip);
Define a table having a compound primary key and create an index on it.
CREATE TABLE mykeyspace.users ( userID uuid, fname text, lname text, email text, address text, zip int, state text, PRIMARY KEY ((userID, fname), state) ); CREATE INDEX ON mykeyspace.users (state);