tree 9351fd444e08da3900ca51f10cd5e04e20fac62b
parent de4631f62cc06b22199c1c14b687ea8a06ea06ec
author Julian Hyde <jhyde@apache.org> 1685209828 -0700
committer Julian Hyde <jhyde@apache.org> 1685247458 -0700

[CALCITE-5717] RelBuilder.project of literals on a single-row Aggregate should create a Values

If RelBuilder.project is applied to an Aggregate with no group keys
(which always returns one row) and all of the projected expressions are
literals, then the result should be a Values with one row.

For example,
  SELECT 42 FROM myTable GROUP BY ()
becomes
  VALUES 42
(Both queries always return one row, even if myTable is empty.)

Close apache/calcite#3209