ydb/yql/essentials/tests/s-expressions/suites/Pg/ColumnRefs.yqls

(
#comment
(let config (DataSource 'config))
(let res_sink (DataSink 'result))
(let data (FormatType (TupleType 
     (TypeOf (PgStar))
     (TypeOf (PgQualifiedStar 'a))
     (TypeOf (PgColumnRef 'a))
     (TypeOf (PgColumnRef 'a 'b)))))
(let world (Write! world res_sink (Key) data '('('type))))
(let world (Commit! world res_sink))
(return world)
)