Read this SQL tutorial to learn when to use SELECT, JOIN, subselects and UNION to access multiple tables with a single statement. It’s sometimes difficult to know which SQL syntax to use when ...

The DICTIONARY tables component is specified in the FROM clause of a SELECT statement. DICTIONARY is a reserved libref for use only in PROC SQL. Data from DICTIONARY tables are generated at run time.

You can implement automatic lookup for any column in a table that can be accessed from the SQL Query window. An action automatically occurs when that column and an operator is selected from the Where ...