ssis transaction with out Msdtc - sql-server

One of the packages is going to implement using
SQL Server Integration Services SSIS Transactions without MSDTC.
The Execute SQL task has placed ,before the data flow(Df_insert) for begin transaction.There are several update steps and index creation steps ,after this First data flow(Df_Insert).There is an update scripts which is in another sequence container and ,need to be part of this transaction.
Is there any way to include only the Df_insert and the update scripts
in the transaction.
The control flow looks like, the below

From SQL Transaction point of view ALL DML statements, i.e. inserts-updates-deletes, between BEGIN TRAN and COMMIT are part of this transaction and not deducible. Your task - committing only DFT and update script - means that update, update2 and delete are temp data used in your update script and discarded later on.
Approach - rework your logic to move results of update, update2 and possibly delete results into TEMP tables and use it afterwards. Regular #temp_table will be fine since you have to use RetainSameConnection=true for transaction without MSDTC.

Related

Breaking a connection to SQL Server halfway through an execution

If I execute a script against SQL, which has multiple transactions in it, but break the connection half way through, what does SQL do? Does it run the script to completion, or just roll-back the transaction it was currently in (or finish it)?
When SQL Server detects that a connection is broken, it should rollback any current transaction and abort the current batch1.
Any preceding committed transactions will still be committed.
1Here I'm trying to draw the distinction between scripts and batches. Many client tools support scripts containing multiple batches (delimited by GOs) and its the batches that get submitted to SQL Server, sequentially.
Well, depends, if there are multiple transactions in the script SQL, do you put commit into each transaction ? for example, if your script like this
BEGIN TRAN --Transaction 1
INSERT TableA VALUES(value1,value2)
COMMIT TRAN
BEGIN TRAN --Transaction 2
INSERT TableB VALUES(value1,value2)
COMMIT TRAN
if your sql server disconnected, half-way of the execution of the whole script, but while on the way of execution of the script and the sql server has completed transaction 1, and that's committed, then transaction 1 is completed, and you can see the result on tableA, but when the sql server running transaction 2 imidiately and few moment later the transaction 2 yet incomplete and the connection gets down, transaction 2 will be rollbacked, so you cant see the result on TableB
Only committed transactions will be executed.
Other ones will do a roll-back.

Transaction from vb.net to insert data into different SQL Server

I have two SQL Server. I want to get data from the first one to the second and to update the first with value sent=1 there are not on the same area
What I want to do exactly is a transation in vb.net that can union all the query that will be applicated to the both db
Is it possible because if I put the query of the first db in a transaction and if i make if transaction = true then execute the second truncation (that applicated to the second db) if I lost the connection that may because problem any one can help me to join all the querys on the same transaction
In VB you would use the TransactionScope class to wrap your data access operations. It will create a local transaction to begin with and then promote it to a distributed transaction when required. The SQL Server Distributed Transaction Manager must be active for that to be possible, so that's something for you to read up on.

SSIS transaction management MSSQL

I need to copy data from DB "source" to db "destination" should the copying fail, I need to roll back on "destination". The two connections are defined in the connection manager as OLE DB.
Here is my current attempt which is not working. I tried playing around with the in-built transaction managemen (setting the tasks transaction to required) but that only made it impossible to connect to "destination".
The destination has set "RetainSameConnection" = true, while this is false for "source" for no particular reason.
I also set the "MaxConcurrentExecutables" = 1 in to hinder SSIS from executing my rollback as the first thing.
Each of the tasks in the sequence is set to "Isolation level"=ReadUncommitted and "transactionOption"=supported.
The "failing script" is a script that always fail in order for me to test the transaction is working.
The code for the task "begin tran" is "BEGIN TRANSACTION " and the connection is set to "destination"
The Code for the task "rollback tran" is "rollback transaction" and the connection is set to "destination"
The rollback fails with "the rollback transaction request has no corresponding 'BEGIN TRANSACTION'"
You are mixing two concepts here. There are 2 ways to achieve transactions in SSIS. The first is SSIS Transactions. Here, your package should be set to TransactionOption = Supported, you container should be set to TransactionOption = Required (which will begin a transaction) and then your two Data Flow Tasks would need to be set to TransactionOption = Supported, which would make both of them join the open transaction. However, please not that this option requires Distributed Transaction Coordinator and there is no way around that.
The second way of achieving transactions is with SQL Native Transactions. Here, you would have an Execute SQL Task that starts a transaction, followed by your Data Flow Tasks and then another Execute SQL that commits the transaction (and of course another to rollback). The issue here, is that it is a requirement that all of the tasks I have just mentioned Use the same connection manager and that retainsameconnection = True on that connection manager otherwise it will not work, as SSIS and SQl Server still regard it as a distributed transaction, even though they are not on the same server, and you would have to use BEGIN DISTRIBUTED transaction, which again requires Distributed Transaction Coordinator. Also I recall that Distributed Native SQL Transactions do not work properly in SSIS.
The short answer is that you cannot achieve what you are trying to do with transactions in SSIS. An alternative would be to use a compensation block. Here, on failure of insert, you would have an Execute SQL Task that deletes the data you have just inserted, based on either Time, or a SELECT MAX(ID), which ever suits your requirements best.

What happens to connections when taking SQl Server Database Offline?

I have recently tried a big merge of 2 databases. We recreated the schema from Database 2 into Database 1 and created a script to transfer all data from database 2 into Database 1. This script takes about 35 min to run and have transaction handling with:
BEGIN TRANSACTION
...
IF(##error<>0)
COMMIT TRANSACTION
ELSE
ROLLBACK TRANSACTION
The full script is a bit sensitive but here is some SQL that have the same structure: http://pastebin.com/GWJ3ZnkF
We ran the script and all data was transfered without errors. We tested the systems running with the new combined database (removed access rights to the old database).
But as a last task we wanted to take the old database offline to make sure no one used that database. To do this we used:
ALTER DATABASE <dbname> SET OFFLINE WITH ROLLBACK IMMEDIATE
This was bad. After this line of SQL code all data in the combined database that we just copied was suddenly gone. I first asumed it wasn't really finished so the "Rollback immediate" sounds like it have performed a rollback on my transaction..
But why? Wasn't the transaction allready committed?
Also I tried running the same script again a few times but after every attempt no data was copied even if it said the script was successfull. I have no idea why... did it remember my offline rollback somehow?
What is really happening to my connections?
Sounds like you had a pending transaction uncommitted and you forced it to rollback, loosing some of the work. The rest is explained by how your scripts are structured. Is unlikely your script had a single transaction from start to bottom. Only the last transaction was rolled back, so the database was left now in a state in which it is 'half copied'. Probably your script does various checks and this intermediate state sends the script on the 'ELSE' branches where it does not do the proper work (ie. apparently does nothing).
W/o posting the exact script, is all speculation anyway.
Right now you need to restore the database to a consistent state, the one before your data copy. Use the backup you took before the data move (you did take a backup, right?). for extra credit, make sure your script is idempotent and works correctly on a half-updated database.
I'd double-check to make sure that there are no outstanding transactions. Either go through the file and count the number of BEGIN TRANSACTION vs COMMIT TRANSACTION lines, or add a statement to the end of it to SELECT ##TRANCOUNT to ensure that there are no open transactions remaining.
If your data has been committed, there should be no way it can be lost by disconnecting you.
WITH ROLLBACK IMMEDIATE:
All incomplete transactions will be rolled back and any other
connections to the database will be
immediately disconnected.
Sounds like someone got the 2 databases mixed up or maybe there is an outstanding transaction?.... Can you post your entire script?
Ref: ALTER DATABASE.
Rather than only checking ##ERROR, inspect ##TRANCOUNT as well.

Script for running DDL statements in a transaction

I am trying to execute a bunch of DDL statements in a transaction scope. I am trying to execute all the statements that relate to a model change request as as a single transaction so that all the DDL statements fail or succeed together. My objective is not to leave the DB in an inconsistent statement after the execution of the group of DDL statements.
I have found that SQL Server 2008 R2 supports transactions on DDL statements. I am not talking about DROP DB kind of DDL statements - I am referring to CREATE TABLE, ALTER TABLE, DROP TABLE, etc.
I have read the following related threads but did not find an answer.
Is it possible to run multiple DDL statements inside a transaction (within SQL Server)?
Unit testing DDL statements that need to be in a transaction
DDL scripts in a transaction block takes effect even when there are errors
What I need is a template script for executing a set of DDL statements as a transaction and to roll them back if one of the statements fail and I want the error to be printed or to be stored in an error table. Can anyone help?
In my research, I have found multiple alternatives, but I am not sure which one to pick as I am new in this area. I need some help from experienced hands.
Use XACT_ABORT in the transaction scope to abort on first error within the transaction
Use a TRY and CATCH block and put the DDL statements inside a transaction inside TRY block
Here are the pages that I have read through.
http://msdn.microsoft.com/en-us/library/ms179296.aspx
http://msdn.microsoft.com/en-us/library/ms188792.aspx
http://www.codeproject.com/KB/database/sqlservertransactions.aspx
Download Red Gate SQL Compare and see how the scripts are generated there.
This does transactional DDL and can be extended for logging.
TRY/CATCH doesn't span batches which makes is trickier to use without dynamic SQL

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