#   

Swapping is a technique in which the values of two variables are exchanged.
To swap two elements in different columns in SQL, we must first create a table and insert some rows. The table below is a sample table containing three attributes—`id`, `FName`, and `LName`—of five students.

We will swap the first name and last name of the student whose `id` is equal to `1`.

## Before swap

Before the swap, the first name contains "Ali," and the last name contains "Asghar."


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## After swap

After the swap, the first name will contain "Asghar" and the last name will contain "Ali."

## Swapping process
The logic of swapping two elements is the same in SQL as in other programming languages. To swap two elements, we need to follow the steps mentioned below:

1) Save the value of the first element in a temporary variable.
2) Assign the second element to the first element.
3) Assign the temporary variable to the second element.

The code below is the implementation of the process described above:

-- Step 1: Store the value of FName in a temporary variable
SET @temp = (SELECT FName FROM Student WHERE id = 1);

-- Step 2: Update the values of FName and LName, swapping their values
UPDATE Student
SET FNAme = LName,
    LName = @temp
WHERE id = 1;

-- Show the values of FName and LName, after swapping their values
select * from Student;

## Code explanation
Here is the line-by-line explanation of the code given above:

* **Line 2:** Stores the value of `FName` into `temp` where the `id` is `1`.

* **Lines 6:** Stores the value of `LName` into `FName`.

* **Lines 7:** Stores the value of `temp` into `LName`.

* **Line 8:** Conditional statement ensures that the values of the specific row are swapped where the `id` is equal to `1`.

* **Line 11:** After swapping the values, prints the table to check whether the values have been swapped.

How to swap two elements in different columns in SQL

Swap values in SQL: Use a temporary variable to exchange data between two columns.

id	FName	LName
1	Ali	Asghar
2	Wahid	Ali
3	Ahmed	Yasser
4	Ali	Sultan
5	Dian	Suqlain

id	FName	LName
1	Asghar	Ali
2	Wahid	Ali
3	Ahmed	Yasser
4	Ali	Sultan
5	Dian	Suqlain