Use lateral view [outer] explode. A lateral view first applies the UDTF to each row of base table and then joins resulting output rows to the input rows to form a virtual table having the supplied table alias. This is example from Presto migration from Hive docs: SELECT student, score FROM tests LATERAL VIEW explode(scores) … Read more
Yes, that is a feature of Postgres and parallel unnesting is guaranteed to be in sync (as long as all arrays have the same number of elements). Postgres 9.4 adds a clean solution for parallel unnest: Unnest multiple arrays in parallel The order of resulting rows is not guaranteed, though. Actually, with a statement as … Read more
Clean setup: CREATE TABLE tbl ( given_date date , set_name varchar ); Use a singular term as column name for a single value. The data type is obviously date and not a timestamp. To transform your text parameters into a useful table: SELECT unnest(string_to_array(‘2001-01-01to2001-01-05,2001-01-10to2001-01-15’, ‘,’)) AS date_range , unnest(string_to_array(‘s1,s2’, ‘,’)) AS set_name; “Parallel unnest” is … Read more