Re: UNION and PROJECT in ISQL

In article <kcjDBBKzB.CKK@netcom.com>, kcj@netcom.com says... >My question is: are there the standard relational operators available in >these products? Specifically I need UNION and JOIN, but I can't see >reference to them at all. There is no JOIN operator in SQL. Instead of joining a.primary_key=b.secondary_key, or a.field1=a.field2, you just add it to the "where" clause, something like "where a.field1 = b.field1 and a.field2 = b.field2 and a.field3 = b.field3" (and so forth). The union operator is certainly not described very well (at least in the Informix Guide to SQL that I'm looking at.) The place to look for a halfway decent description is probably the Tutorial manual; it basically goes something as follows: select field1, field2, field3 from table where {where conditions} union select field1, field2, field3 from table where {other where conditions} and returns the union of the two select statements. -- William Harris (Standard disclaimers) CARS Information Systems http://www.carsinfo.com/~william/ 4000 Executive Park Drive Cincinnati, OH (USA) 45241