Add support for min(Row[N]) and max(Row[N])

[lukaseder]

H2 seems to support MIN and MAX aggregate functions for row value expressions, which is a very useful feature (#9113 (comment)). They can be emulated.

• In most RDBMS with ORDER BY .. LIMIT correlated subqueries, but that's quite difficult to get right.
• In some RDBMS using ARRAY_AGG or COLLECT, which allows for ordering group elements, and accessing only the first element.

[katzyn]

You may want to suggest a FILTER clause to exclude nulls from aggregation, because row value with nulls will be aggregated otherwise.

[lukaseder]

That might actually be the desired effect :) (Then we'll have to think about NULLS FIRST vs NULLS LAST semantics...)

[lukaseder]

See also: See also: #11998