Recursion in SQL

Stored Procedure for calculating the Recursion

CREATE PROC sp_Factorial
@InPara int,
@OutPara int OUTPUT
AS
DECLARE @InCalc int
DECLARE @OutCalc int
IF @InPara != 1
BEGIN
SELECT @InCalc = @InPara - 1
EXEC sp_Factorial @InCalc, @OutCalc OUTPUT
SELECT @OutPara = @InPara * @OutCalc
END
ELSE
BEGIN
SELECT @OutPara = 1
END
RETURN GO

Following is the code to execute the SP "sp_Factorial"

DECLARE @CalcOut int
DECLARE @CalcIn int
SELECT @CalcIn = 6
EXEC sp_Factorial @CalcIn, @CalcOut OUTPUT
PRINT ' factorial of ' + CAST(@CalcIn AS varchar) + 'is ' + CAST(@CalcOut AS varchar)
GO

Different types of joins in SQL Server

INNER JOIN
LEFT OUTER JOIN
RIGHT OUTER JOIN

Indexes retrieve the data quickly

There are two types of indexes in SQL Server.
Clustered index
Non Clustered index

Normalization is the first step for DB

First Normal Form

Second Normal form

Third normal form: