In this post, I am sharing a script for comparing the table difference in SQL Server.

For comparing or taking the difference of tables is a very common task for most of the database developers.
So you guys can access the below simple demonstration on this.

Create two sample tables:

CREATE TABLE tbl_ABC (Rno INT, Name VARCHAR(20))
GO
CREATE TABLE tbl_XYZ (Rno INT, Name VARCHAR(20))
GO

Insert sampel records:

INSERT INTO tbl_ABC 
VALUES (1,'A'),(2,'B'),(3,'D'),(4,'E')
GO
INSERT INTO tbl_XYZ
VALUES (1,'A'),(2,'C'),(3,'D'),(4,'F')
GO

Compare and Find the table differences:

SELECT Rno, Name FROM
(
    SELECT Rno, Name FROM tbl_ABC
    UNION ALL
    SELECT Rno, Name FROM tbl_XYZ
) A
GROUP BY Rno, Name
HAVING COUNT(*) <> 2

Result:

Rno         Name
----------- ---------
2           B
2           C
4           E
4           F

In this post, I am sharing few scripts for getting the column differences of the similar table in SQL Server.

If your table has a number of columns like more than 100, it is very difficult to compare the column with another same table.
Mostly, we are doing this kind of comparison between production database and other sprint databases.

You can access the below small demonstration on this:

Create two sample tables:

CREATE TABLE tbl_ABC (Rno INT, Name CHAR(20), Class INT)
GO
CREATE TABLE tbl_XYZ (Rno INT, Name VARCHAR(20))
GO

Find the difference of column datatype:

select
	ic1.TABLE_NAME
	,ic1.COLUMN_NAME
	,ic1.DATA_TYPE
	,ic2.TABLE_NAME
	,ic2.DATA_TYPE
	,ic2.COLUMN_NAME
from INFORMATION_SCHEMA.COLUMNS as ic1
left join INFORMATION_SCHEMA.COLUMNS as ic2
on ic1.COLUMN_NAME=ic2.COLUMN_NAME
where ic1.TABLE_NAME='tbl_ABC'
and ic2.TABLE_NAME='tbl_XYZ'
and ic1.data_type <> ic2.DATA_TYPE

Result:

Find extra column from another similar table:

select
	ic2.TABLE_NAME
	,ic2.COLUMN_NAME
from INFORMATION_SCHEMA.COLUMNS ic2
where table_name='tbl_ABC'
and ic2.COLUMN_NAME not in
(select column_name
from INFORMATION_SCHEMA.COLUMNS
where table_name='tbl_XYZ')

Result: