We have a small development team of 5 developers working on a large enterprise level web based asp.net/c# system.
We do a lot of database updates which include stored procedure creations and alters as well as new table creation, column creation, record inserts, record updates and so on and so forth.
Today all of the developers place all change scripts in one large sql change script file that gets ran on our Test and Production environments. So this single file contains stored proc alters and record inserts, updates etc etc. The file can end up being quite lengthy as we may only do a test or production release every 1 to 2 months.
The problem that I am currently facing is this:
Once in a while there is a script error that may occur at any given location in this large “batch change script”. Perhaps an insert fails or perhaps an alter fails for a proc for instance.
When this occurs, it is very difficult to tell what changes succeeded and what failed on the database.
Sometimes even if one alter fails for instance code will continue to execute throughout the script and sometimes it will stop execution and nothing further gets ran.
So I end up manually checking procs and records today to see what actually worked and what actually did not and this is a bit painstaking.
I was hoping I could roll up this entire change script into one big transaction so that if any problem occurred I could just roll every change back, but that does not appear to be possible with batch scripts like this in sql server.
So, then I tried to backup the databases before I ran the scripts so that if an error occurred I could simply restore the db, fix the problem and then re-run the fixed script. However in order to restore a database I have to turn off our database mirroring so this is also not totally ideal.
So my question is, what is the safest way to run batch scripts on a production database?
Is there some way that I can wrap the entire script in a transaction that i can roll back that I am not seeing?
Would it possibly be better for us to track and run separate script files so that if 1 file fails we can just shove it off in a failed directory to be looked at and continue running all other files?
Looking for advice and expertise.
thank you for your time.
Matt
The batch script should be run on your QC database first so that any errors are picked up before production.
The QC database should be identical to production or as close as it can be to identical.
Each script should be trapping for an error and reporting the name of the script along with the location of the error using print statements, then if an error occurs when applying to production you at least have the name of the script and the location of the error within the script.
If your QC database is identical or very close, productions errors should be very rare.