Basic Language Elements › Column Names › Column-Name Qualifiers to Avoid Ambiguity

Column-Name Qualifiers to Avoid Ambiguity

In the context of a function, GROUP BY clause, ORDER BY clause, expression or a search condition, a column-name refers to values of a column in some table or view.

The tables and views that could possibly contain the column are called the object tables of the context. Two or more object tables could possibly contain columns with the same name.

One reason for qualifying a column-name is to designate which table the column comes from.