Talk:Relational calculus

Remark
Is there A relational calculus, or are there relational calculi? The first sentence of this article confuses the point by stating "The relational calculus refers to the two calculi...". This is something i've been wondering about since learning the differential and intergral calculus(es). 144.226.230.36 22:22, 7 April 2007 (UTC)Clebio
 * There's a relational calculus, which involves two other calculi. That is, "The relational calculus" is collective. -- Mikeblas 04:25, 8 April 2007 (UTC)

It means that relational calculus consist of "tuple relational calculus" and "domain relational calculus". Both are used to express SQL statements mathematically. The difference is in the syntax. --Joieko (talk) 12:44, 9 December 2007 (UTC)

Someone please help this page
This is a key part of into to database and other non-database systems (RDF) and this needs a decent article. —Preceding unsigned comment added by 69.137.225.247 (talk) 06:53, 15 March 2011 (UTC)