Restriction and AND - SQL
Restriction is available via the WHERE operator, and so it is in SQL. However, by Example showing how a certain simple restriction can be expressed using JOIN and a relation literal. It is useful to show SQL's counterpart of that example, giving the student ids of students named Boris.
Example: joining with a table literal
SELECT DISTINCT StudentId
FROM IS_CALLED NATURAL JOIN (VALUES ('Boris')) AS T(Name)
The columns of a table literal in SQL are anonymous. When a table literal is an operand in a table expression the only way of assigning names to its columns is by giving them in the definition of a range variable-AS T(Name) in the example.