The results of two queries can be combined using the set operations union, intersection, and difference. The syntax is

As shown in the previous section, the table expression in the SELECT command constructs an intermediate virtual table by possibly combining tables

After a query has produced an output table (after the select list has been processed) it can optionally be sorted. If sorting is not chosen, the rows will be returned in an

VALUES provides a way to generate a "constant table" that can be used in a query without having to actually create and

LIMIT and OFFSET allow you to retrieve just a portion of the rows that are generated by the rest of the query:

The process of retrieving or the command to retrieve data from a database is called a query. In SQL the

A table expression computes a table. The table expression contains a FROM clause that is optionally followed by

WITH provides a way to write auxiliary statements for use in a larger query. These statements, which are often referred to as Common Table Expressions