Im wondering something regarding this article:
https://learn.microsoft.com/en-us/azure/sql-database/sql-database-manage-application-rolling-upgrade
We would like to perform a database upgrade involving ~3 million records in a table. The upgrade will add an extr column to the mentioned table, which can take up to 5 minutes to complete.
In short, Microsoft suggest creating a transactionally consistent database copy of the target database, perform the database upgrade/migration and switch users to that copy using a load balancer.
This seems all and well, but records created in the original database will not be present in the upgraded/migrated database copy.
Turn the primary database to read-write mode and run the upgrade script in the stage slot (5). - is what the article suggest.
If the primary database is read-write mode, won't i be missing data in the upgraded/migrated copy of the primary database once i point everyone to the new database?
For example: would it be possible to sync database records from the primary to the secondary once the secondary is upgraded and front-end users are pointed to the secondary database?
Related
I have a relational database in my server where I've used for developing a system. Now I want to make it live and truncate all data from the tables. I've manually deleted data from tables and after that I've run the truncate command, but it show this error :
Cannot truncate table 'dbo.Building' because it is being referenced by a FOREIGN KEY constraint.
Is there any way to empty my database by using a single command? I've searched google, all of them told to use truncate command. But I can not use it for all the tables because the error occurred.
I want to entry data from the ID no 1 in all tables.
Please give me a guideline to truncate all the data from my database.
Now I want to make it live and truncate all data from the tables
You are approaching this completely wrong. Even if you succeed, you will deploy a system which will be impossible to upgrade. As you continue to develop you will modify the development database and then when you have to deploy your next version of your application you'll realize you need to modify the production database and keep all of its data.
Stop the deployment right now and go back to the drawing board to design a proper deployment strategy. I recommend migrations. Another alternative is using diff tools.
Truncating tables is completely irrelevant for what you're actually trying to achieve.
There are two options I could think off..
You need to drop (not just disable ) all foreign keys, then finally run truncate to delete all table data using any method.. and finally recreate all foreign keys
You also can script out only DDL and deploy database using that script instead of providing database to deployment team..
Could you please suggest the easiest way to programmatically (not via UI) generate a script to migrate specific tables (schema, constraints, indexes) to another database on a separate server.
I am aware of replication, SSIS, generate scripts feature, backup-restore approach and SQL Import/export window. However, all these approaches require at least some kind of UI interaction or don' allow to copy constraints or don't allow to migrate only part of data.
Database where I will be putting the data will be in sync with main DB, so it is possible to just wipe-off existing data in it and overwrite with schema and data from main DB.
From Comment: I need to migrate only part of DB: specific tables with their foreign key/primary key constraints, indexes AND data from these tables
as per my understanding i hope this will help you
Click Next
Choose your Location
USE DATABASE: FALSE will help you to execute script in your New DB which you created in your new server basically it will not generate Create DB script
Read carefully Table View/Option whatever you need please make it true
Click Next Pickup script file from your location and run on your new server
There are 2 Oracle databases with the same tables on two different servers. Database A on server A and Database B on server B
A: Table1,Table2
B: Table1,Table2
These tables are identical to each other, in that it's possible to copy the data tables from server A to server B. We only have remote access to the database on Server A, but full admin access to Server B.
So, database A is remote and has a primary and secondary DB. The secondary DB gets updated with the latest data, then we must switch the DB we're pointing to towards secondary. Same for the opposite, when things are pointing to secondary, primary DB will get updated with data, then the system should point to Database A primary. This way the database is never down we just switch what we point to after the other one gets updated.
There is also a web interface that sets a config file whether we're pointing to the primary or the secondary DB
Now, I'm trying to come up with solutions on how to get/synchronize/copy/point to the correct database to get the updated data either directly from A or by copying data A to B.
Solution 1) We read db config file and point directly to the primary (or secondary) DB
Solution 2) Build a windows service that will detect when primary or secondary DB gets updated, and copy tables from DataBase A to DataBase B.
Solution 3) Have a "copy tables" button on the web interface that will start a background task of copying data from A to B using http://hangfire.io
Solution 4) ??
So far, I like the idea of solution 1 the best, where we just point directly to either the primary or secondary DB based on configuration. This idea doesn't involve any copying to the identical tables on Server B.
However, I was wondering if there is any other possible solution? Would triggers, replication, or something else work here?
Thanks.
This involves data replication, kind of:
We have many sites with SQL Express installed, there is an 'audit' database on each site that has one table in 1st normal form (to make life simple :)
Now I need to get this table from each site, and copy the contents (say, with a Date Time Value > 1/1/200 00:00, but this will change obviously) and copy it to a big 'super table' in sql server proper, that also has the primary key as the Site Name (That needs injecting in) and the current primary key from the SQL Express table)
e.g. Many SQL Express DBs with the following table columns
ID, Definition Name, Definition Type, DateTime, Success, NvarChar1, NvarChar2 etc etc etc
And the big super table needs to have:
SiteName, ID, Definition Name, Definition Type, DateTime, Success, NvarChar1, NvarChar2 etc etc etc
Where items in bold are the primary key(s)
Is there a Microsoft (or non MS I suppose) app/tool/thing to manager copying all this data accross already, or do we need to write our own?
Many thanks.
You can use SSIS (which comes with SQL Server) to populate, it can be set up with variables to change the connection string to the various databases. I have one that loops through the whole list and does the same process using three differnt files from three differnt vendors. You could so something simliar to loop through the different site databases. Put the whole list of database you want to copy the audit data from in a table and loop through it changing the connection string each time.
However, why on earth would you want one mega audit table per site? If every table in the database populates the audit table as changes happen, then the audit table eventually becomes a huge problem for performance. Every insert, update and delete has to hit this table and then you are proposing to add an export on top of that. This seems to me to be a guaranteed structure for locking and deadlocks and all sorts of nastiness. Do yourself a favor and limit each audit table to the table it is auditing.
Things to consider:
Linked servers and sp_msforeachdb as part of a do-it-yourself solution.
SQL Server Replication (by Microsoft) (which I believe can pull data from SQL Server Express)
SQL Server Integration Services which can pull data from SQL Server Express instances.
Personally, I would investigate Integration Services first.
Good luck.
You could do this with SymmetricDS. SymmetricDS is open source, web-enabled, database independent, data synchronization/replication software. It uses web and database technologies to replicate tables between relational databases in near real time. The software was designed to scale for a large number of databases, work across low-bandwidth connections, and withstand periods of network outage.
As of right now, however, you would need to implement a custom IDataLoaderFilter extension point (in Java) to add the extra column. The metadata would be available though because your SiteName would be the external_id.
We have a production SQL Server 2005 database server with the production version of our application's database on it. I would like to be able to copy down the data contents of the production database to a development server for testing.
Several sites (and Microsoft's forums) suggest using the Backup/Restore options to copy databases from one server from another, but this solution is unworkable for several reasons (I don't have backup authority on our production database, I don't want to overwrite permissions on the development server, I don't want to overwrite structure changes on the development server, etc...)
I've tried using the SQL Import/Export Wizard in SQL Server 2005, but it always reports primary key violations. How can I copy the contents of a database from the production server to development without using the "Backup/Restore" method?
Well without the proper rights it really becomes more tedious and less than ideal.
One way that I would recommend though is to drop all of your constraints and indexes and then add them again once the data has been imported/exported.
Not an elegant solution but it'll process really fast.
EDIT:
Another option is to create an SSIS package where you specifically dump the tables in an order that won't violate the constraints.
I often use SQL Data Compare (http://www.red-gate.com/products/sql_data_compare/index.htm) for this task: the synchronization scripts it writes will remove the relationships during the transfer and reapply them, but that is OK in most development cases. It works especially well with smaller databases or subsets of databases.
If your database is large, I would recommend finding someone with the keys to the kingdom. Doing an out of sequence backup could mess with the ability to restore the database from the primary backup (if they are doing partials during the week for example) by marking records backed up when they are only in your backup, so don't try to bypass that security if you are unsure why it is there.
Assuming that you can connect to both DB's from the same machine (which almost always you can - I do it with my production servers via a VPN).
For each table
DELETE FROM devserv.dbo.tablename;
SET identity_insert [devserv.dbo.tablename] ON;
INSERT into devserv.dbo.tablename SELECT * from prodserv.dbo.tablename;
SET identity_insert [devname.dbo.tablename] OFF;
It is obviously worth noting that you will need to do this in a certain order if your tables have foreign key constraints.
The import/ export wizard is notorious for this sort of thing, and actually has a bug that makes it even less useful in working out the dependencies (sorry, don't have the details to hand).
SSIS does a much better job, but you'll have to add each table copy task by hand (in fact a datasource, copy task and data destination objects. It's a little tedious to set up (more than it should be), but a lot simpler than writing your own code.
One tip: avoid generating an SSIS project with the import/ export wizard, thinking it will be easier to just tweak it. It generates something that most people would find unrecognisable, even with some SSIS experience!
If you do not have backup permission on the production server, I guess this is because you are using a shared SQL Server from a webhoster. In this case, check if your webhoster provides the tool called myLittleBackup. It allows installing a db from one server to another in a few clicks...
I'd contact someone that does have access to backup the database. Permissions are usually there for a reason.
I might consider getting a backup as there will be one wether you run it or not (t least in theory a Prod DB is being backed up :) )
Then just restore to a brand new database on your dev box so you dont conflict with anything or anyone else.
If you restore to a new DB you could also pull the tables and data across manually if you wanted and since you create the DB you give yourself rights and it's all ok. There's a number of other methods, all tedious.
It is obviously worth noting that you will need to do this in a certain order if your tables have foreign key constraints.
We just use the SQL Server Database Publishing Wizard at work.
You would use this little utility to generate a T-SQL script that describes your production database (including all its data). Then connect to your dev server and run the generated script.
If you have to avoid backup/restore this is what I would recommend (these steps assuming you don't want to maintain the old schema NAME, just the structure) -
Download opendbdiff. Choose 'Compare' between source and (empty) destination. Choose sync. script tab and copy only the create table rows (without dbo.sysdiagrams tables etc.) paste into sql managment studio new query, delete all the schemas names appearing before the table names.
Now you have the full structure including primary keys, identity etc. Next step - use sql server import and export data like you did before (make sure you choose edit mappings and choose destination schema as dbo etc.). Also make sure you tick drop and recreate destination table.
On your Dev machine, setup a linked server to your production machine. Then just
INSERT dev.db.dbo.table (fieldlist)
SELECT (fieldlist) from prod.db.dbo.table