[regrep] Inner joins using Entry level SQL-1992

[Richard Martell <rmartell@galdosinc.com>]

Hi


The question came up during the last telecon about expressing joins
using SQL in ebRS. It appears that ebRS 6.4.1 _does_ allow (inner)
joins, since SQLTableList can have more than one table reference. But
this is non-normative. The preamble in 6.4 (which should be incorporated
into a new normative subsection 6.4.1) is normative, however, and
doesn't appear to rule out (inner) joins either. It requires the use
of Entry-level SQL-1992 only.

This is the classic formulation of an inner join supported by
Entry-level SQL-92:

SELECT TableA.Field1, TableB.Field2, blah, blah
FROM TableA, TableB
WHERE TableA.Field1=TableB.Field2


However, this conformance level does _not_ encompass the following
syntax (which is allowed in Intermediate SQL); it should produce
the same results:

SELECT TableA.Field1, TableB.Field2, blah, blah
FROM TableA INNER JOIN TableB
ON TableA.Field1=TableB.Field2


-- 
Richard