Introduction
Let’s see how easy it is to do such a thing.
A few things need to be kept in mind while doing this; the two columns should have the same data type, and the length should be good enough to hold the swapped value; otherwise, the data would be truncated. Let us see one practical demonstration of the same.
Let us create a table with the following structure and insert a few records.
create table Student
(
StudentID Int identity primary key,
FirstName varchar(30),
LastName varchar(30),
Marks Int
)
Insert into Student(FirstName,LastName,Marks) Values('Nitin','Tyagi',400)
Insert into Student(FirstName,LastName,Marks) Values('Ajay','Sharma',300)
Insert into Student(FirstName,LastName,Marks) Values('Vikrant','Sharma',100)
Let us check the table contents.
Select * from Student
Let us now swap the values of FirstName and LastName. Write the following query to achieve the same.
Update Student Set FirstName=LastName,LastName=FirstName
Let us check the output. Execute the below query.
Select * from Student
Summary
As we can see, the values have been swapped between the two columns. Swapping in SQL is pretty easy.
Reference