[mysql] how to concat two columns into one with the existing column name in mysql?

I want to concatenate two columns in a table with a existing column name using mysql.

An example: I am having a column FIRSTNAME and LASTNAME and so many columns also. I want to concatenate these two columns with the name of FIRSTNAME only.

So I tried like this:

 SELECT *, CONCAT(FIRSTNAME, ',', LASTNAME) AS FIRSTNAME FROM `customer`;

but it displaying the two fields with the name of FIRSTNAME. one field is having normal values and another one is having concatenated values. I want only one column with those concatenate value. I can select single columns, but am having more than 40 columns in my table.

Is there any way to remove the original column using mysql itself?

This question is related to mysql

The answer is


You can try this simple way for combining columns:

select some_other_column,first_name || ' ' || last_name AS First_name from customer;

Just Remove * from your select clause, and mention all column names explicitly and omit the FIRSTNAME column. After this write CONCAT(FIRSTNAME, ',', LASTNAME) AS FIRSTNAME. The above query will give you the only one FIRSTNAME column.


I am a novice and I did it this way:

Create table Name1
(
F_Name varchar(20),
L_Name varchar(20),
Age INTEGER
)

Insert into Name1
Values
('Tom', 'Bombadil', 32),
('Danny', 'Fartman', 43),
('Stephine', 'Belchlord', 33),
('Corry', 'Smallpants', 95)
Go

Update Name1
Set F_Name = CONCAT(F_Name, ' ', L_Name)
Go

Alter Table Name1
Drop column L_Name
Go

Update Table_Name
Set F_Name

Instead of getting all the table columns using * in your sql statement, you use to specify the table columns you need.

You can use the SQL statement something like:

SELECT CONCAT(FIRSTNAME, ' ', LASTNAME) AS FIRSTNAME FROM customer;

BTW, why couldn't you use FullName instead of FirstName? Like this:

SELECT CONCAT(FIRSTNAME, ' ', LASTNAME) AS 'CUSTOMER NAME' FROM customer;

Remove the * from your query and use individual column names, like this:

SELECT SOME_OTHER_COLUMN, CONCAT(FIRSTNAME, ',', LASTNAME) AS FIRSTNAME FROM `customer`;

Using * means, in your results you want all the columns of the table. In your case * will also include FIRSTNAME. You are then concatenating some columns and using alias of FIRSTNAME. This creates 2 columns with same name.