I will write a letter to santa asking to get this into sql. During 10 years in data warehouse I constantly wondered why SQL does not have something like that.

I will write a letter to santa asking to get this into sql. During 10 years in data warehouse I constantly wondered why SQL does not have something like that. Reducing verboseness is nice, but the main perk is the correctness. Oh.. if I got a cent every time I found a bug in colleagues sql, because of join accidentally multiplying/doubling rows... :-)