I need help with making a primary key automatically increase its value in SQL Server 2012. I’m trying to create a table where each new record gets a unique ID number that goes up by 1 each time.
I found some information about using the Identity specification settings in the column properties, but when I try to change the Identity option from “No” to “Yes”, it appears disabled and won’t let me modify it. The increment value field is also grayed out.
Is there a different way to accomplish this? I’m working with SQL Server Management Studio and just want to make sure each row gets its own unique identifier automatically when inserted.
Interesting issue! What happens if you delete rows later? Will identity gaps matter for your use case? Also - are you inserting tons of records at once or one at a time?
You cannot change the Identity property on an existing column in SQL Server. It must be defined when the table is created. If your table already has data, you can either create a new table with the Identity setting and transfer the data or add a new Identity column using ALTER TABLE, set it as the primary key, and then remove the old column. It’s advisable to define IDENTITY(1,1) along with your PRIMARY KEY constraint initially to prevent such issues.
yep, totally get it! that identity stuff is tricky. you can’t change it after the table is made. just gotta set it right when creating it, like this: CREATE TABLE ... ID int IDENTITY(1,1) PRIMARY KEY. if the table’s already there, you might have to recreate it. good luck!