Cloudera Docs

Modifying the external JDBC table

You can use the ALTER TABLE statement to add, drop, or modify columns, or modify the table properties of existing external JDBC tables. The syntax is the same as the other Impala tables.

Run the ALTER TABLE statement to modify columns and table properties:
  • Using ALTER TABLE statement to add, drop, or modify columns
    ALTER TABLE student_jdbc ADD COLUMN IF NOT EXISTS date_col DATE;
ALTER TABLE student_jdbc DROP COLUMN int_col;
ALTER TABLE student_jdbc CHANGE COLUMN date_col timestamp_col TIMESTAMP;
  • Using ALTER TABLE statement to modify table properties
    ALTER TABLE student_jdbc
SET TBLPROPERTIES ("dbcp.username"="impala", "dbcp.password"="password");