When I use A.column name, B.Column name where A = Table A and B = Table B , what is the technical name for the A.Column name? Is it a prefix, identifier or what else?
They also call it a "Correlation Name"
http://publib.boulder.ibm.com/iseries/v5r1/ic2924/index.htm?info/db2/rbafzmstc2cornm.htm
I think correlation name is properly the alias used in a correlated subquery. In the query below E2 is the correlation name.
SELECT EMPNO, LASTNAME, WORKDEPT, EDLEVEL FROM EMPLOYEE WHERE EDLEVEL > (SELECT AVG(E2.EDLEVEL) FROM EMPLOYEE E2 WHERE E2.WORKDEPT = WORKDEPT )
From my copy of "SQL-99 Complete, Really":
A
<Correlation name>
(or alias) identifies a variable that ranges over some Table; that is, a variable whose only permitted values are the rows of a given Table.
So either "alias" or "correlation name" is acceptable. Though "alias" is also used for column aliases defined in the select-list, so if you use this term you should be clear about which one you mean.