At the time of this writing Redshift does not support the PostgreSQL RETURNING fields syntax nor JDBC Statement.RETURN_GENERATED_KEYS. If you attempt something like:

SQL"""INSERT INTO ...""".executeInsert(long("id"))  

you'll be rewarded with:

java.sql.SQLFeatureNotSupportedException: [Amazon][JDBC](10220) Driver not capable.  

To get around this you need to wrap things inside a transaction and get the maximum ID value from the table - straight from 1998:

SQL"BEGIN;".execute()  
SQL"""INSERT INTO table_x (date_created, name, source, meta)  
      VALUES (${dateCreated.toDate}, $name, $source, $meta);""".execute()
val result = SQL"""SELECT MAX(id) FROM table_x;""".executeQuery().single(long(1))  
SQL"COMMIT;".execute()  
result