Recover and Roll back SQL DB State - sql-server

Friends,
I'm looking for an solution on SQL DB server. I'm being working in support organization on managing SQL Server.
When we make some changes on SQL DB (Schema changes, table alteration, data etc..) and found it is not compatible we need to roll back easily.
Something like, before i make any changes on my DB server need to preserve current state of DB and once changes were made and if looks good then i can commit permanantly. If not working properly i can discard the changes and revert to previous state quickly.
Is there any such option available?

You can create Database Snapshot which helps to prevent administrative error.
Here is a link that can help you understand how to create and apply database snapshot:
Database Snapshot

Related

migrating database back to original database entity framework migrations

I have made some changes to a database using code first entity framework migrations (lets say db2).
I now want to revert the change made back to the original database. As we want to retain the data on the old database (db1) I cant simple clone it.
Can someone please confirm the right process to do this?
I am assuming I will need to perform a rollback on db2 back to the original state it was in when it was cloned from db1.
I would then switch context so I am pointing at db1.
I then add a migration to generate all the database changes.
I then perform update-database to run make the changes.
Is this correct?
I will then need to run a migration to br
You can use –TargetMigration parameter in order to migrate to a specific version:
Update-Database –TargetMigration: db1
More info.

SSDT implementation: Alter table insteed of Create

We just trying to implement SSDT in our project.
We have lots of clients for one of our products which is built on a single DB (DBDB) with tables and stored procedures only.
We created one SSDT project for database DBDB (using VS 2012 > SQL Server object Browser > right click on project > New Project).
Once we build that project it creates one .sql file.
Problem: if we run that file on client's DBDB - it creates all the tables again & it deletes all records in it [this fulfills the requirements but deletes the existing records :-( ]
What we need: only the update which is not present on the client's DBDB should get update with new changes.
Note : we have no direct access to client's DBDB database for comparing with our latest DBDB. We only can send them some magic script file which will update their DBDB to the latest state.
The only way to update the Client's DB is to compare the DB schemas and then apply the delta. Any way you do it, you will need some way to get a hold on the schema thats running at the client:
IF you ship a versioned product, it is easiest to deploy version N-1 of that to your development server and compare that to the version N you are going to ship. This way, SSDT can generate the migration script you need to ship to the client to pull that DB up to the current schema.
IF you don't have a versioned product, or your client might have altered the schema or you will need to find a way to extract the schema data on site (maybe using SSDT there) and then let SSDT create the delta.
Option: You can skip using the compare feature of SSDT altogether. But then you need to write your migration script yourself. For each modification to the schema, you need to write the DDL statements yourself and wrap them in if clauses that check for the old state so the changes will only be made once and if the old state exists. This way, it doesnt really matter from wich state to wich state you are going as the script will determine for each step if and what to do.
The last is the most flexible, but requires deep testing in its own and of course should have started way before the situation you are in now, where you don't know what the changes have been anymore. But it can help for next time.
This only applies to schema changes on the tables, because you can always fall back to just drop and recreate ALL stored procedures since there is nothing lost in dropping them.
It sounds like you may not be pushing the changes correctly. You have a couple of options if you've built a SQL Project.
Give them the dacpac and have them use SQLPackage to update their own database.
Generate an update script against your customer's "current" version and give that to them.
In any case, it sounds like your publish option might be set to drop and recreate the database each time. I've written quite a few articles on SSDT SQL Projects and getting started that might be helpful here: http://schottsql.blogspot.com/2013/10/all-ssdt-articles.html

How do I log every data change that has been made in SQL Server?

I have a profile page (less than 10k users) and I need to track every change and update that is made through out the application, by the users. Whether a user updates the profile picture or adds an extra space in a "comments" field, I need to store the previous data.
In short: I need to store everything.
Is there some sort of "tracking-history-and-changes-in-sql-server" software or do I have to implement it myself?
If I have to implement it myself I can think of three ways to do it:
I keep everything in the same table
but I add a key column that
specifies which row is active
and which is old.
I add a new table called history
where I store the column name that had the
change, when it was changed and what
the old data was.
I add a history table for each table
in the database. It looks the same
but only keep track of each tables
history.
Has anyone had a similar problem and how did you solve it?
This was built using mvc 4 and it's a
normal website.
EDIT
I'm mostly interested in existing solutions/software, but If there are none I would have to do it myself.
Has anyone used SQL Data Compare?
Where I worked last everything had to be logged fully. (working with goverment organisations). We never updated or deleted data.
What you would do is have a start date and an end date on each row. To do an update you would update the old data to have an enddate then insert a new row in the table. To do a delete you would put an enddate on the row with a null enddate. We also had an "updated by" column to put the userid
I used the third approach to do that but didn't create a history table for all tables of my DB but history tables for most important tables. You can use triggers to do that , create trigger for Update. You can read more about Triggers here and here
Microsoft offers Change Tracking and Change Data Capture for awhile now. These technically offer the tracking of all your changes in your database, which suits your purpose. Just note that CT is available in most versions, whereas CDC used to be only available in Enterprise until SQL Server 2016, where they made it available for Standard too.
ApexSQL Log does pretty much the same as well, but if you're using SQL Server then it's integrated in your software already.
have you considered enabling full transaction logging on your database and then using some of the log reading tools to monitor data changes. ApexSQL Log is by far the best log reader on the market but there are other solutions out there. SQL Log Rescue from Red Gate is free but it's only for sql server 2000.
Using this approach you dont need to make any other changes in your database or in your application since every transaction is automatically logged when database is in full recovery mode.
Hope this helps.

Can we get Altered stored procedure

Hi by mistake I've altered one stored procedure and is there any chance to get that old procedure?
Thank you
There is no reason whatsoever to not put your database in source control and treat it like any other code. You should NEVER make a change to a database without a source control script. This means never ever using the GUI to make database changes.
The only way to get back what you replaced is to restore a backup or if you have the other version on a another server, then script it and re-run on the server you you changed.
Yes fixing your source control problem is an emergency, you and your team should not write anymore code of any kind until this is done.
Restore a backup of the affected database onto another server to get the old procedure's code, then copy just that code over.
If you don't have a spare server, you can restore the database to a different database on the same server. (create a new database, then restore the backup to that - just pay attention that you're restoring onto your new/temporary database, then delete that database when you're finished)
Red-Gate has SQL log rescue which might have helped (it's for SQL2000), but there might be other solutions available.

Sql Server Replication: Snapshot vs Merge

Background information
Let's say I have two database servers, both SQL Server 2008.
One is in my LAN (ServerLocal), the other one is on a remote hosting environment (ServerRemote).
I have created a database on ServerLocal and have an exact copy of that database on ServerRemote. The database on ServerRemote is part of a web application and I would like to keep it's data up-to-date with the data in the database ServerLocal.
ServerLocal is able to communicate with ServerRemote, this is one-way traffic. Communication from ServerRemote to ServerLocal isn't available.
Current solution
I thought it would be a nice solution to use replication. So I've made ServerLocal a publisher and subscriptions are pushed to the ServerRemote. This works fine, when a snapshot is transfered to ServerRemote the existing data will be purged and the ServerRemote database is once again an exact replica of the database on ServerLocal.
The problem
Records that exist on ServerRemote that don't exist on ServerLocal are removed. This doesn't matter for most of my tables but in some of my tables I'd like to keep the existing data (aspnet_users for instance), and update the records if necessary.
What kind of replication fits my problem?
Option C: Transactional replication.
I've done this before where you have data in a subscription database and don't want it overwritten by the snapshot. You can set your initial snapshot to not delete the existing records and either don't create the records that are in the publisher (assume they are there) or create the records that are in the publisher (assume they are not there).
Take a look at what would be correct for your situation or leave a comment with more details on how you get your data in the subscriber originally. I'm not too familiar with aspnet_users and what that is. Transactional replication only helps if you don't want the data in the subscriber back at the publisher. If you want that you'll have to do merge replication.

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