If a column is not associated with an explicit table name, tables named in the SQL statement are searched, and one of the following occurs.
| Situation | Result |
|---|---|
| Matching column found in only one table | Requested information is returned. |
| Matching column found in two or more tables | Ambiguous column name error is reported. |
| Matching column not found | NAMED list is searched for the column name. "Named" names are not valid when used to fully qualify a table name. |
| Column name not found in SQL statement or in NAMED list | Nonexistent column error is reported. |