What is difference between transaction in SQL Server and using transaction in ADO.NET?
Please reply with proper logic. I just want to know in terms of performance.
I just want to know if i am using transaction(Begin End Trans) and using SqlTransaction class in ado.net for similar set of queries then which is better to use ?
There is no difference between a ADO.Net transaction and SQL Server transaction, as far as transaction handling. Personally, I prefer initiating transactions at a higher level that ADO.NET offers, because it normally gives me greater flexibility in setting the scope of the transaction.
SQL Server level transactions only when I need to update Multiple Tables, like I have a Master Table, and a Detail Table, I want to update both the Master and Detail tables.
ADO.Net (.Net Level) transaction only for one project, it is an SQL 2008 project, there was some requirement like, I need to save some DOC files in Database, it is using a SQL 2008 feature, called FileStream. If enable FileStream it will create some shared folder on the server, and Saves all the file data into this Folder, which can only read by SQL Server.
An ADO.net transaction is more convenient if you are making changes to multiple databases within a transaction and want to roll all of them back in case of an error.
Related
AFAIK, Memcached does not support synchronization with database (at least SQL Server and Oracle). We are planning to use Memcached (it is free) with our OLTP database.
In some business processes we do some heavy validations which requires lot of data from database, we can not keep static copy of these data as we don't know whether the data has been modified so we fetch the data every time which slows the process down.
One possible solution could be
Write triggers on database to create/update prefixed-postfixed (table-PK1-PK2-PK3-column) files on change of records
Monitor this change of file using FileSystemWatcher and expire the key (table-PK1-PK2-PK3-column) to get updated data
Problem: There would be around 100,000 users using any combination of data for 10 hours. So we will end up having a lot of files e.g. categ1-subcateg5-subcateg-78-data100, categ1-subcateg5-subcateg-78-data250, categ2-subcateg5-subcateg-78-data100, categ1-subcateg5-subcateg-33-data100, etc.
I am expecting 5 million files at least. Now it looks a pathetic solution :(
Other possibilities are
call a web service asynchronously from the trigger passing the key
to be expired
call an exe from trigger without waiting it to finish and then this
exe would expire the key. (I have got some success with this approach on SQL Server using xp_cmdsell to call an exe, calling an exe from oracle's trigger looks a bit difficult)
Still sounds pathetic, isn't it?
Any intelligent suggestions please
It's not clear (to me) if the use of Memcached is mandatory or not. I would personally avoid it and use instead SqlDependency and OracleDependency. The two both allow to pass a db command and get notified when the data that the command would return changes.
If Memcached is mandatory you can still use this two classes to trigger the invalidation.
MS SQL Server has "Change Tracking" features that maybe be of use to you. You enable the database for change tracking and configure which tables you wish to track. SQL Server then creates change records on every update, insert, delete on a table and then lets you query for changes to records that have been made since the last time you checked. This is very useful for syncing changes and is more efficient than using triggers. It's also easier to manage than making your own tracking tables. This has been a feature since SQL Server 2005.
How to: Use SQL Server Change Tracking
Change tracking only captures the primary keys of the tables and let's you query which fields might have been modified. Then you can query the tables join on those keys to get the current data. If you want it to capture the data also you can use Change Capture, but it requires more overhead and at least SQL Server 2008 enterprise edition.
Change Data Capture
I have no experience with Oracle, but i believe it may also have some tracking functionality as well. This article might get you started:
20 Using Oracle Streams to Record Table Changes
I have an SQL Server(SQL Azure) table that is being queried at a high rate, but gets updated only few times a month.
I wonder what options do I have that can cache the result set on the application side so that it will not have to hit SQL Server all the time.
One option is to just [OutputCache] the action methods which return the views. You may even be able to get away with SQL Dependency caching, though not sure if this works with Azure.
Another option is to try implementing a second-level cache for EF.
Another option is to have an entirely different read model. This way, you wouldn't query against the table, but something else that is closer to IIS and/or faster than SQL Azure (like NoSQL or JSON from Azure cache).
Just about everything I've seen relating to ASP.Net's Login control treats it like a black box. I'm interested in seeing the SQL commands issued against ASPNETDB and watching the dataflow.
For example, the Login control uses ASPNETDB and stored procedure dbo.aspnet_Membership_FindUsersByName. I'm not clear on how to call the procedure because it expects #PageIndex and #PageSize parameters (#ApplicationName and #UserNameToMatch make sense to me). I would like to read about the procedure or trace it.
Would anyone know of good reading on the topic, or suggest a path to explore the control?
What you are looking for is called a SQL Server Trace. The Graphical User Interface for SQL Traces is SQL Server Profiler. This only ships with certain versions of SQL Server (for instance, if you have SQL Server Express Edition then you will not have SQL Server Profiler, but you will still be able to utilize the Trace stored procedures and database objects).
Using Profiler (or the Trace db objects), you'll be able to filter out certain events and data depending on what you are specifically looking to capture. This will give you all the information you'll need to find out the data being transmitted to and from the server -> client application (or in this case, the ASP.NET application).
The events and data that a Trace puts forth can be extremely daunting, especially if you are new to this (which it sounds like you are) and there are a lot of hits to the database. Learn about the Profiler Templates you can utilize, and the individual Events you can analyze.
If you have access to SQL Server, then fire up the profiler and you can see in real-time the sql statements executed against the db.
Just for good measure a brief step by step guide for starting up profiler.
Starting up SQL profiler
If your using SQL express you may not have profiler, however here's an open source alternative (note. I've never used it)
free profiler
If you set it up to use SQL Server (using aspnet_regsql.exe), you can see the stored procedures it uses.
I have to maintain transactions between two different databases. I need to rollback if there is any error occurred in Database1 then all changes in database2 should be rollback.
I have two connection string in my web.config file.
The answer depends on if you need distributed transactions between two database server instances, or transactions between two databases in a single instance. In the first case you'll need a transaction manager like MSDTC, but in the second case the database server should be able to do the job by itself.
TransactionScope will escalate the transaction to MSDTC if necessary. The rules for this are somewhat subtle. If the two databases are on a single SQL Server 2008 instance, you shouldn't need MSDTC.
See also:
TransactionScope automatically
escalating to MSDTC on some
machines?
Common Gotchas when
using TransactionScope and MS DTC
You could use the TransactionScope class:
using(var tx = new TransactionScope())
{
// TODO: your DB queries here
tx.Complete();
}
I was wondering what is the easiest way to see total number of database queries from my ASP.Net (.NET 2.0) application.
My application heavily use sql 2005 database because all data are dynamic and everything goes through one connection string in web.config. Connection pooling is enabled there.
So, I am wondering how many select statements are executed for particular page I load in my browser.
I don't care if I can see that information from .net side or from db side as long as I can see only connections to MY database. Not all connections to that db server because I use shared db server and there is a lot of other databases.
The best way to do this is to set up a profiler on your database and then make a single request to your ASP.NET application. The profiler will aggregate any data you wish and you will be able to use that data to determine what queries were sent to SQL Server from your application.
The SQL Server Profiler will list all actions performed on your DB. If you use a different db login name for your project (probably a really good idea if you are not) you can filter so it only shows actions from your login (see Events Selection, Column Filters then Login Name).
Use SQL Profiler. You can configure it to filter by the database you want and to just show select statements.
If you have some sort of database layer in your code, you could modify it to write out a log message every time you run a select statement. Then just load the page once and count the number of log statements. This may or may not work, depending on how your code is structured, but it's an option.
Edit: I misread the question. I thought you had multiple clients connecting to the same database, not the same database server. In that case, a profiler probably is the best choice.
Do you have access to SQL Server Profiler? You can set up traces to monitor this sort of thing by loading a page and looking at the effects in the profiler.
JUst be aware that Profiler can affect performance, so it is best to do this on dev.