How to migrate Azure SQL Database to another Azure SQL Database - sql-server

Question

I have one SQLServer in Azure portal and in that server has 2 SQL Databases TestDB1 and TestDB2 is copy of TestDB1. But we used TestDB2 for testing and now it has more data compared to TestDB1. I want to migrate only unavailable data from TestDB2 to TestDB1 as both are having same DB schema. How to do it?

Answer 1

Something like this might work, I've tested it locally and it does merge in test data from a sperate database, full example shown
USE [Playground2] -- Swap for your database name
CREATE TABLE MyTable (
Id BIGINT NOT NULL IDENTITY(1,1) CONSTRAINT PK_MyTable PRIMARY KEY,
[Name] NVARCHAR(50),
[Age] INT,
)
INSERT INTO MyTable([Name], [Age])
VALUES('Andrew', '28'),
('Robert', '38'),
('James', '40'),
('Robin', '40'),
('Peter', '56'), -- second database has this extra data
('Steve', '22') -- second database has this extra data
GO
USE [Playground] -- Swap for your database name
CREATE TABLE MyTable (
Id BIGINT NOT NULL IDENTITY(1,1) CONSTRAINT PK_MyTable PRIMARY KEY,
[Name] NVARCHAR(50),
[Age] INT,
)
INSERT INTO MyTable([Name], [Age])
VALUES('Andrew', '28'),
('Robert', '38'),
('James', '40'),
('Robin', '40')
GO
-- Check that the tables have slightly different data
SELECT * FROM Playground.dbo.MyTable
SELECT * FROM Playground2.dbo.MyTable
BEGIN TRANSACTION
BEGIN TRY
SET IDENTITY_INSERT dbo.MyTable ON
MERGE INTO dbo.MyTable AS TGT
USING [Playground2].dbo.MyTable AS SRC -- Note that we point to the other database here seeing as it is on the same SQL instance
ON TGT.Id = SRC.Id
WHEN MATCHED THEN
UPDATE SET
TGT.[Name] = SRC.[Name],
TGT.[Age] = SRC.[Age]
WHEN NOT MATCHED THEN
INSERT(Id, [Name], [Age])
VALUES(SRC.Id, SRC.[Name], SRC.[Age])
OUTPUT $action AS [Action],
deleted.[Name] AS OldName,
inserted.[Name] AS [NewName],
deleted.[Age] AS OldCountry,
inserted.[Age] AS NewCountry;
SET IDENTITY_INSERT dbo.MyTable OFF
SELECT * FROM dbo.MyTable
ROLLBACK TRANSACTION -- Change to COMMIT TRANSACTION when you are happy with the results
END TRY
BEGIN CATCH
PRINT 'Rolling back changes, there was an error!!'
ROLLBACK TRANSACTION
DECLARE #Msg NVARCHAR(MAX)
SELECT #Msg=ERROR_MESSAGE()
RAISERROR('Error Occured: %s', 20, 101,#msg) WITH LOG
END CATCH
But there also will be tools to do this, but this could be one answer, cheers