How to add a new column in sql server based on Select query

Question

I have just created a simple query the concatenate 2 columns and create a column with this concatenation.

Now I want to ADD a new column to the table base on the below query

SELECT Convert(NVARCHAR(50), [cell_name]) + '_' + Convert(NVARCHAR(50), [n_cell_name]) AS st_gsm_df_relation_key FROM [myDB].[dbo].[gsm_df_relation]

I want ALTER TABLE or something based on this query.

Yogesh Sharma · Accepted Answer · 2020-01-29 15:30:23Z

Use alter :

alter table table_name add st_gsm_df_relation_key_ as Convert(nvarchar(50),[cell_name])+'_'+Convert(nvarchar(50),[n_cell_name]);

You can also use concat() :

alter table table_name add st_gsm_df_relation_key_ as concat(Convert(nvarchar(50),[cell_name]), '_', Convert(nvarchar(50),[n_cell_name]));

concat() will ignore nulls when either cell_name or n_cell_name have null.

@MahmoudAl-Haroon, it's good that you found a useful answer. Please consider accepting the answer by clicking on the grey check mark to the left. It rewards the person who answered with some reputation points, and you get some, too.

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