[MichaelGG]

Both TSQL and pgsql miss stuff. But yesterday I wanted to turn a (customerid, key, value) table into a JSON object, one per customer. Simple one liners in other systems, but a mess in TSQL, requiring "FOR XML PATH" hackery. There's also an unsupported/deprecated/undocumented trick of updating a var inside a select (select @a = @a + column).