Case Statement in SQL WHERE Clause

DECLARE @FirstName VARCHAR(100)

SET @FirstName = ''

 

DECLARE @LastName VARCHAR(100)

SET @LastName = 'John' 

 

SELECT FirstName, LastName

FROM Contacts

WHERE  

    FirstName = CASE

    WHEN LEN(@FirstName) > 0 THEN  @FirstName

    ELSE FirstName

    END

AND

    LastName = CASE

    WHEN LEN(@LastName) > 0 THEN  @LastName

    ELSE LastName

    END

GO

Working With Null Values in SQL

SELECT Field1,Field2,ISNULL(Field3,'') + ' ' + isnull(Field4,'') as Parm1 FROM TableName 

Remove Restoring On SQL Database

RESTORE DATABASE  DB_Name WITH RECOVERY
GO

Custom Validation Message with HTML5

< input type="text" id="username" required placeholder="Enter Name" oninvalid="this.setCustomValidity('Enter User Name Here')" oninput="this.setCustomValidity('')"/>