SQL Functionality for the Impala™ Wire Protocol Driver : Selecting Data With the Driver : Select List : Column Name Qualification

Column Name Qualification
A column can only be qualified with a single name. Furthermore, a table can be qualified with a database (ODBC 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.
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

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