How to use Common Table Expression in PL/SQL Block

SQL Server provides the option to use Common Table Expressions not only in SQL Queries rather we can use them in a PL/SQL Block. The only thing that we have to take care of is that the immediate line preceding the Common Table Expression must be ended with a semi colon. For e.g.

begin

declare @vTempVariable varchar(20)
Select @vTempVariable=dname from table;

With MyCte(ColumnA, ColumnB) as
(
Select ColumnA, ColumB from table1
)

Select *, ColumnA, ColumnB from TableX, Mycte

end

In the above code, we can see that we have used a semi colon in the SQL Statement that is preceding immediately the Common Table Expression. If we don't use semi colon, it will throw an error.

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Rohit Dhand

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