DUAL System Table Description

Description

The SQL standard requires that any query that is made must be from a table. DUAL is a helpful pseudo table that allows you to query expressions that don’t require data from a table.

Example

SELECT now() FROM dual;
           [NOW]
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 2020-07-27 17:08:17.607256

SQL> SELECT 52*5 FROM dual;
 [*]
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 260