A column can only be qualified with a single name. Furthermore, a table can be qualified with a database (JDBC schema) name in the FROM clause, and in some cases, must also be aliased. Aliasing may not be necessary if the database qualifier is not the current database.
The driver can work around these limitations using the Remove Column Qualifiers connection option.
If set to 1, the driver removes three-part column qualifiers and replaces them with alias.column qualifiers.
If set to 0, the driver does not do anything with the request.
Suppose you have the following ANSI SQL query:
SELECT schema.table1.col1,schema.table2.col2 FROM schema.table1,schema.table2 WHERE schema.table1.col3=schema.table2.col3
If the Remove Column Qualifiers connection option is enabled, the driver replaces the three-part column qualifiers:
SELECT table1.col1,
table2.col2 FROM schema.table1 table1 JOIN schema.table2 table2
WHERE table1.col3 = table2.col3
If set to 1, the driver removes three-part column qualifiers and replaces them with alias.column qualifiers.