# Exists

> The `exists` predicate specifies a result set of values to match in a `where` clause.

> ## Syntax

>         select * from ...
>         where exists (select valX from ... where ...)

> The `not` operator can be added to an expression using `in`:

>         select * from ...
>         where not exists (select valX from ... where ...)

> ## Examples

>         create table dep(id int, name char(20));
>         create table emp(name char(20), deptId int);
>         insert into dep values([1,2,3],['Sales','Customer Service','Technical Support']);
>         insert into emp values(['Smith','Jones','Black','Clark','Adams'], [3,3,1,2,1]);

>         select name from emp where exists (select * from dep where id = emp.deptId and dep.id = 1);
>         name
>         ------------------------------------------------------------------------------
>         Black
>         Adams

>         Selected records: 2

> For more examples please see xSQL SDK sample `exists`.