How to compare data between two different columns in two different databases with SQL

Question

Hello I am new to SQL server and I have two databases with two different tables, they are on the same server and I am using Microsoft SQL Server management studio. I need to compare two columns and find which entries do not show up in both columns. Some of these results do match up and I only want to find the differences.

Databases and fields that need querying:

database1, ID number database2, complex ID number

I would just like to find out the entries that do not match up between the two using SQL.

Thanks for your help!

Answer 1

You just need to make sure to reference each piece with the 3 or 4 part name.

Database.Schema.Table when referencing tables and Database.Schema.Table.Column when referencing columns

You can write joins between databases this way and definitely pull data from more than one database.

Answer 2

use linked server see this link

read all, at the end you have the use of sql statements use