I need to make a local copy of a database in a .NET app so that it can function offline. My server database is SQL Server 2005, and it's copying to SQL Server 2008 Express.
It doesn't have to be anything fancy - just start from scratch (or delete the existing db), copy all tables/constraints/foreign keys, and copy data from some of the tables. I don't mind keeping a "schema version" in my database so that the app knows when its existing schema is outdated.
I've been looking into the Microsoft Sync Framework, and it appears that I have to make a SyncTable for each table in my database, and frankly, that seems like too much work and maintenance. This is the code that I'm finding in examples:
SyncTable orderDetailSyncTable = new SyncTable("OrderDetail");
orderDetailSyncTable.CreationOption = TableCreationOption.DropExistingOrCreateNewTable;
orderDetailSyncTable.SyncDirection = SyncDirection.Snapshot;
orderDetailSyncTable.SyncGroup = orderSyncGroup;
this.Configuration.SyncTables.Add(orderDetailSyncTable);
I suppose I could list all the tables in my database and enumerate over them, but it just seems like there should be a better way. Am I missing something in the Sync Framework, or is there something else that would accomplish this sort of thing?
I gave up on Sync Framework; using SQL Server Management Objects to accomplish this instead.
http://msdn.microsoft.com/en-us/library/ms162169.aspx
Related
I need your help to manage an issue with my C# program. I wrote a GUI that allows the user to manage a lot of data stored in a SQL Server database. Everything works fine but I want to be sure that the application works even when the server is down (for a generic issue).
My plan is to have a local database (e.g. *.mdf database used in Visual Studio) and update it every time the GUI is able to connect to the online SQL Server database.
What do you think? Is there something similar to a procedure or do I need to do it manually (create a .mdf file, check the online version, write the changes etc.)?
Apart from the comments noting that this may not be a good idea (which I agree):
Most of the work must be done manually. If you have a DB model within your application (like when using entity framework) it could be that it can create the DB structure in the local file. Most of your data will need timestamps to determine when they were changed the last time.
The Microsoft Sync Framework might utilize you but I have not used it personally. Look here http://msdn.microsoft.com/en-us/library/bb902854(v=sql.110).aspx
I am looking for a solution in which several applications on the same machine access one and the same database. Generally the operations are just reads thus I am not interested in having to provide concurrent write access as well.
I checked into SQL Server Express, SQL Server LocalDb, SQL CE, SQLite, MySQL and am not convinced which one is the best solution. I read that SQL CE allows concurrent read access but SQL Server LocalDb does not, which I find very odd given LocalDb is hyped by MS as a version that is very similar in functionality to the SQL Server family and which is supposed to make it easy to later on scale out.
I like to manage 5-10 tables each of which holds less than 5000 rows, so really lightweight content.
I am looking for a solution that meets the following requirements:
Concurrent read access by several applications on the same machine
Should be somewhat lightweight. I intend to move all applications within a solution to a different machine later and do not want to have to install a 200mb full blown SQL Server Ex#ress version if possible.
Should play well with VS2012 express (sqlite and mysql are highly unsupported in that regards, either not supporting EF5 or they do not show up in the server explorer.
Should be an SQL solution in order to manually update database tables within a management console such as Workbench or Management Studio or other third party app.
Should work somewhat with EF or other ORM solution. I want to be able to create an entity class and create a database from that or update tables using class objects. Also I want to populate class object collections from table rows without having to go through SQL code.
I target C# in .Net 4.5 and I guess it boils down to the question whether SQL CE is up to the task to allow concurrent reads and how I can load CE data tables and edit and visualize the content in some sort of management console. Also does SQL CE play well with EF5? Any better suggestions?
Since you're asking for an opinion, SQLite is my answer.
We are aware of no other embedded SQL database engine that supports as
much concurrency as SQLite. SQLite allows multiple processes to have
the database file open at once, and for multiple processes to read the
database at once. When any process wants to write, it must lock the
entire database file for the duration of its update. But that normally
only takes a few milliseconds. Other processes just wait on the writer
to finish then continue about their business. Other embedded SQL
database engines typically only allow a single process to connect to
the database at once.
Entity Framework on SQLite
System.Data.SQLite
Setups for 32-bit Windows (.NET Framework 4.5)
This setup package is capable of installing the design-time components for Visual Studio 2012.
SQL CE Works with EF5 and VS 2012 Express, is very lightweight, supports multiple readers on the same machine, and can be managed in VS Pro+ combined with the SQL Server Compact Toolbox add-in (or standalone) (I am the author)
I know there's a lot of material on this topic, but somehow I really can't find anything not out of date and for my needs.
What I need.
I have a local SQL Express 2008 R2 Database
I need to sync this Database over WCF with a Server Database (SQL 2008 R2)
I ONLY NEED ONE WAY "DOWNLOAD" SYNCHING meaning, that the client Database is always overridden by the Servers.
How can I accomplish that?
I am trying for several days to get it work with the Microsoft Sync Framework 2.1.
Thank you!
have you looked at this sample?
Database Sync:SQL Server and SQL Express N-Tier with WCF
If you really won't need any data to go back into your server database from the client, then using MSF2.1 is overkill for what you need. It would probably be faster and easier to build (or find) a tool that makes an "insert or update" stored procedure for every table in your database. With that in place and the proper timestamps and delete flags in every table, you should be able to accomplish it with significantly less overhead than implementing the sync framework.
Also, if you haven't already taken a look at it, have a look at the web sync replication option: http://msdn.microsoft.com/en-us/library/ms151763.aspx
I have a simple app written using SQL Server, Entity Framework, C# and WCF. When I wanted to share this app with my friends, I realised they didn't use SQL Server on their machine. I could go for SQL Server Express edition, as the usage of my app is personal and non-commercial.
I found MySQL as a popular alternative to SQL Server.
1) Would I be required to update my entities when moving to MySQL?
2) Should I anticipate code changes in my BL layer due to change in entities layer? (I am wondering whether entities was built for SQL Server)
Are there any databases similar to MS Access that is lightweight compared to MySQL?
Are there any databases that need not be installed but can be copied around like MS Access?
Appreciate your response!
Sounds like you want SQLite.
SQLite is a software library that
implements a self-contained,
serverless, zero-configuration,
transactional SQL database engine.
Very easy to deploy. Also, check out System.Data.SQLite.
According to the System.Data.SQLite page ...
Supports nearly all the entity
framework functionality that Sql
Server supports, and passes 99% of the
tests in MS's EFQuerySamples demo
application.
You should be good. :)
Im not sure how your BLL looks like and i have no experience with entity framework, but ive experienced multiple times that linq-to-sql works much better with sql-server as with any other database.
So unless you have a good reason not to use sql express, i'd advice to stick to sql express.
After all, you should always install something when deploying (unless you use xml as storage, which is quite well possible with linq-to-xml).
VistaDB Express Edition is also free for non-commercial usage and integrates good into .NET and VS. afaik it also works on a single local data file thus requires no specific installation on your friends' computers.
Otherwise I recommend using PostgreSQL over MySql since it is more standards compliant and has a nicer license.
I think what you're after is just a change in providers. What you need to use MySQL is the .Net Connector which supports most everything simple. It's not very mature yet so something very complex you may have issues on, but it should do most of what you want through Entity Framework.
With Entity Framework yes you can do updates, it's LINQ-to-SQL that doesn't update against any other databases (unless you use a third party provider like DotConnect)
SQLite is one alternative, but since multiple threads against it can cause major issues with it's operation, so if you need a major data store I'd go SQLExpress or MySQL.
Yes, you could use MySql with EF but I don't know if it would require changes.... I wouldn't be surprised if it does though. At the very least your physical DB would have to be ported / converted to MySql and that will take time.
I would assume that if you need to install a DB on your friends Pc's why not stick with SQL Express since you already developed in SQL Server on your box. Should be less issues with this than migrating to MySql.
I'd also vote for VistaDB 3 as it's so easy to deploy.
How do i create a db file in C#? a friend told me it was in the toolbox and not to use sqlite. I dont see anything that could be it, nor what it is called. google didnt help:(
Could it be...
SQL Server Compact Edition – A lightweight, in-process database engine designed to run on devices and desktops and is geared toward local data storage. Compact Edition includes a subset of SQL Server 2005 data types and shares common elements of the Transact-SQL (T-SQL) language with the data service engines.
There is no file-based database provider built in to c# or the .NET Framework. There are of course pre-existing connectors for using SQL Server (which includes SQL Express), but if you need a fully functional RDBMS that is file-based, you need to use something like SQLite or Firebird (also a fan of VistaDB, not free or open source but VERY solid and pretty affordable).
On the Add New Item menu: "Service-based Database" or "Sql Server Database" if it is an asp.net application. I am sure your friend meant it as "create a sql express db file in Visual Studio".
That said, if you wanted to fill an empty database, with tables that correspond to a c# model, you could create a linq2sql model, and use its CreateDatabase to do that for you :)
You might want to check this http://quickstarts.asp.net/QuickStartv20/aspnet/doc/data/vwd.aspx (visual web developer link, but it applies).
For a full/in-depth explanation of how SQL express can be used with a semi file based approach check and its limitations:
http://www.databasejournal.com/features/mssql/article.php/3704171/SQL-Server-2005-Express-Edition---Part-8---XCopy-Deployment.htm
Perhaps you might try Microsoft LocalDB.
It is file based but uses a low level SQLExpress Installation to host it.
If you are using Visual Studio or Web Developer Express, there are indeed ways to easily create a MS SQLExpress database. Just go to Add New Item... and it should be one of the available file types.
Keep in mind you have to have installed either Microsoft SQL Express Edition (free, as in beer!) or Microsoft SQL (very un-free!, in all senses). If you haven't done this, you don't get the option of creating a database file so easily. If you have got it yet, you can get it here.
As other answerers have mentioned, strictly speaking this is NOT a C# feature. MS SQL and it's derivatives, are database applications, much like Oracle, MySQL, or PostgreSQL. It's just that Microsoft Visual Studio makes using the Microsoft database product very easy by default. Differentiating between C#, Visual Studio, and any database programs will probably get you better answers, faster, no matter where you ask. :)
Every database has a file system in some binary format more than likely custom and uses a cache to control the flow of the database(s) lifetime.
If you create a database system, you will need some type of cache because you only want to read from the file if the cache has already released it.
If you have 1000 clients tapping into the same db, you certainly don't want to read/write to the file for each client request, so you want to manage a queue of clients and run it against the cache so that the cache knows not to release the db after its time span for lifetime is reached put to rather update the time span, therefore, not having to reload the file, if disposed and queued again, until the queue referencing the db object is empty.
Creating a well designed cache it used by all rdbms's so that duplicate objects are not created and files are not reloaded if not need be.
You can use
FileDB - A C# database to store files
http://filedb.codeplex.com
There is a MVC Example in the source that allows you to upload files and also has drag and drop support.
It then saves it into just one file in a location that you specified.
Like this:
private string pathDB = #"C:\CMS-MVC\Parts\FileManager\filedb-19055\trunk\MvcTest\Data\MvcData.dat";
That one file will store all of your files in that one "container".
You are mistaken. Databases are not developed in C#. Databases are built using a database system such as Oracle, MS SQL Server, MySQL, and numerous others.
Once you build a database using one of the above providers, you can then perform actions on the database using your programming language of choice (in your case C#) to get data out of and put data into it.