Using "GO" within a transaction

Question

I'm building a web app that attempts to install/upgrade the database on App_Start. Part of the installation procedure is to ensure that the database has the asp.net features installed. For this I am using the System.Web.Management.SqlServices object.

My intention is to do all the database work within an SQL transaction and if any of it fails, roll back the transaction and leave the database untouched.

the SqlServices object has a method "Install" that takes a ConnectionString but not a transaction. So instead I use SqlServices.GenerateApplicationServicesScripts like so:

string script = SqlServices.GenerateApplicationServicesScripts(true, SqlFeatures.All, _connection.Database);
SqlHelper.ExecuteNonQuery(transaction, CommandType.Text, script, ...);

and then I use the SqlHelper from the Enterprise Library.

but this throws an Exception with a butt-load of errors, a few are below

Incorrect syntax near 'GO'.
Incorrect syntax near 'GO'.
Incorrect syntax near 'GO'.
Incorrect syntax near 'GO'.
Incorrect syntax near the keyword 'USE'.
Incorrect syntax near the keyword 'CREATE'.
Incorrect syntax near 'GO'.
The variable name '@cmd' has already been declared. Variable names must be unique within a query batch or stored procedure.

I'm presuming it's some issue with using the GO statement within an SQL Transaction.

How can I get this generated script to work when executed in this way.

Answer 1

GO is not a SQL keyword.

It's a batch separator used by client tools (like SSMS) to break the entire script up into batches

You'll have to break up the script into batches yourself or use something like sqlcmd with "-c GO" or osql to deal with "GO"

Answer 2

I just want to add that if you name your transaction, you can include multiple GO sections within in and they will all roll back as a unit. Such as:

BEGIN TRANSACTION TransactionWithGos;
GO

SET XACT_ABORT ON; -- Roll back everything if error occurs in script
GO

-- do stuff
GO

COMMIT TRANSACTION TransactionWithGos;
GO

Answer 3

Poor man's way to fix this: split the SQL on the GO statements. Something like:

private static List<string> getCommands(string testDataSql)
{
    string[] splitcommands = File.ReadAllText(testDataSql).Split(new string[]{"GO\r\n"}, StringSplitOptions.RemoveEmptyEntries);
    List<string> commandList = new List<string>(splitcommands);
    return commandList;
}

[that was actually copied out of the app I am working on now. I garun-freaking-tee this code]

Then just ExecuteNonQuery() over the list. Get fancy and use transactions for bonus points.

# # # # # BONUS POINTS # # # # # #

How to handle the transaction bits really depends on operational goals. Basically you could do it two ways:

a) Wrap the entire execution in a single transaction, which would make sense if you really wanted everything to either execute or fail (better option IMHO)

b) Wrap each call to ExecuteNonQuery() in its own transaction. Well, actually, each call is its own transaction. But you could catch the exceptions and carry on to the next item. Of course, if this is typical generated DDL stuff, oftentimes the next part depends on a previous part so one part failing will probably bugger the whole pooch.

Answer 4

GO is batch seperator in SQL. It means completion of one entire batch. For Example, a variable defined in one batch @ID can't be accessed after 'GO' statement. Please refer the code below for understanding

Declare @ID nvarchar(5);
set @ID = 5;
select @ID
GO
select @ID

Answer 5

EDIT as pointed out below I specified tran where batch was actually correct.

The issue is not that you cannot use GO within a transaction so much as GO indicates the end of a batch, and is not itself a T-SQL command. You could execute the whole script using SQLCMD, or split it on the GO's and execute each batch in turn.

Answer 6

Actually, you can use GO statements, when you use the Microsoft.SqlServer.Management.Smo extensions:

    var script = GetScript(databaseName);
    var conn = new SqlConnection(connectionString.ConnectionString);
    var svrConnection = new ServerConnection(conn);
    var server = new Server(svrConnection);
    server.ConnectionContext.ExecuteNonQuery(script);

http://msdn.microsoft.com/de-de/library/microsoft.sqlserver.management.smo.aspx

All you need is the SQL CLR Types and SQL Management objects packages deployed from: http://www.microsoft.com/en-us/download/details.aspx?id=29065 (SQL 2012 version)

Answer 7

test your scripts:

• restore a production backup on a backup server
• run run scripts with GOs

install your scripts:

• shut down application
• go to single user mode
• backup database
• run scripts with GOs, on failure restore backup
• go back to multi user mode
• restart application

Answer 8

Just thought I'd add my solution here... replace the 'GO' with a separator that ExecuteNonQuery understands i.e. the ';' operator. Use this function to fix your script:

private static string FixGoDelimitedSqlScript(string script)
{
    return script.Replace("\r\nGO\r\n", "\r\n;\r\n");
}

It may not work for complex nested T-SQL with ';' operators in them, but worked for me and my script. I would have used the splitting method listed above, but I was restricted by the library I was using so I had to find another workaround. Hope this helps someone!

PS. I am aware that the ';' operator is a statement separator and the 'GO' operator is a batch separator, so any advanced scripts will probably not be fixed by this.