I'm having trouble figuring out databases in VB.NET. (VS 2008)
What control(s) do I need to use and how do I use them? I am ,looking for tutorials and sample code too.
I'm working on a trivia game where the admin can remove and add questions to a database.
EDIT:
The program must be able to do all of the DB interactions itself through code.
Regarding DB portability...
I do not intend to install it on many machines, so portability is not a major issue, but I's rather not be bound to Access or SQL Server. (Is that possible? - A portable database file?)
A bit more complaining...
I really need help with connection strings and the whole DB gamut in VB. I've done DBs in PHP so I'm not completely ignorant. It's the VB side of things that's confusing.
Thanks.
Have you considered SQLite DB? It's a very small DB and is used my many vendors. I have not used SQLite personally, but I do know that Firefox uses it and so does iPhone (from what i've read).
SQLite does not require you to install anything (as per the post below). It's a nice alternative to Access or carrying around SQL Server Express.
If you do decide to use SQL Server Express, you will be required to install the run-time, from here for each machine it's used on.
Below are some links which may help you get started
Google for SQLite DB
ADO.NET 2.0 Provider for SQLite
And finally, here's a blog post outlining how to get it done, and quickly.
Cheers!
I would suggest Microsoft's Enterprise Library - The hands on labs available make it a breeze to setup access to a database, and can make it as simple as a config change to point to a new/different DB.
Also, check out http://connectionstrings.com/ for related info.
Related
Despite a few hiccups and a few workarounds, my MVC based Entity Framework (Code First) application is now complete and ready for deployment.
I originally tried developing through SQL Express, however, I had non stop problems with the Code First approach as I asked about here which made it completely unworkable.
So, in the end, I developed it following the majority of guidelines and used SQL Compact Edition. This has been absolutely brilliant for development - but - now it has come to deployment and I am stuck.
I have seen some people saying about generating the Schema from the .SDF file, however, there are differences and restrictions in Compact edition such as nvarchar being limited to a length of 4000, and I need max in my application.
So basically, what can I do?
In addition - but not essential - , I am going to be moving on to the next project shortly, It will involve heavy usage of items needing to be stored in a database that are longer than 4000 characters. Are there any better strategies now for development / Is it possible to use Code First with SQL Server Express or SQL Full (I have MSDN and willing to install/use anything that will help).
Here are my unofficial recommendations:
SQL CE is not a viable option for most production applications that are based on MVC (although I have used it in production services in rare cases).
I would try to avoid switching databases between development and production - i.e., don't test on SQL CE and deploy to SQL Express or something else.
I have never tried to open an MDF inside of Visual Studio - maybe I'm misunderstanding what you're saying here, but in general I'd recommend using the SQL Server-specific tools to manage databases: http://www.microsoft.com/download/en/search.aspx?q=sql+server+management+studio+express.
Regarding the other post, I would generally discourage using the AttachDBFilename portion of connection strings unless you need it for a specific purpose.
It sounds like you may want to review the available database initialization strategies: http://blog.oneunicorn.com/2011/03/31/configuring-database-initializers-in-a-config-file/.
There are lots of walkthroughs on our blog and the MVC MSDN site - if those don't work for you feel free to reach out to us from our blog and provide feedback on what we can do better!
Our blog: http://blogs.msdn.com/b/adonet/
MVC walkthroughs: http://www.asp.net/mvc/tutorials/getting-started-with-mvc3-part4-cs
On the one hand regarding deployment/migration you might want to take a look at http://exportsqlce.codeplex.com
On the other hand I've been checking Microsoft SQL Server Compact 4.0 Books Online and in principle there is no known issues with data types, although the limitation you mentioned for nvarchar is confirmed.
Finally in order to elaborate a strategy you might find interesting the Differences Between SQL Server Compact and SQL Server
You need to create a debug and a release specific web.config file:
In the release specific file you remove the connection string, so it creates a database for you.
In the debug specific file you keep the connection string.
However, I would suggest you to not use a connection string and use SQL Management Studio instead. Given that the Compact Edition does not support your requirement, this is a good time to switch...
Does anybody know of any good tutorials that show how to configure FluentNhibernate for SQL Server 2005/2008. The ones I have found usually just use SQLite, but I would like to see one that specifically targets SQL Server 2005/2008.
I really liked the sample tutorial on the FluentNhibernate website (http://wiki.fluentnhibernate.org/Getting_started#Your_first_project), but it looks like most tutorials I have found seem to only deal with SQLite. It would be great to see a working tutorial that deals with the more common databases in real world applications like SQL Server 2005/2008, MySQL, etc
Thanks!
Tutorials use SQLite not because it's "quick & dirty" but because it's embedded, small, and free. Anyone can download System.Data.SQLite and start working in about 60 seconds, and later switch (or not) to another database with minimum impact. That's one of the major benefits of using an ORM.
Just in case, I want to clarify that SQLite is not a toy database, for many applications it's enough and even necessary since the characteristics I mentioned above aren't too common for a relational databse.
In the case of fluent-nhibernate, the only difference is that instead of:
Fluently.Configure()
.Database(
SQLiteConfiguration.Standard
.UsingFile("firstProject.db"))...
you'll have:
Fluently.Configure()
.Database(
MsSqlConfiguration.MsSql2005
.ConnectionString("a raw string"))...
Each database engine config has its own specific optional settings.
More information about configuring different databases in the fluent-nhibernate wiki.
I have been working on VB6 database desktop programming, but now a client is asking for a
simple web interface (some inserts into SQL Server db used by a desktop application).
The question is: Which approach is better?
1)creating asp.net project, connected directly to the SQL Server database;
2)creating separate (simple) mysql database managed by php and synchronization (in 15 minutes for example)
Thanks.
Personally since you already have the SQL Server database, I see no reason whatsoever to add the complexity of another database and then synchonization. The first alternative is simpler to create and can be secure if you design it correctly. The issue about hosting is irrelevant since you are going to your own database that already exists, so is the issue about cost since the databse is already there. Further since you are already supporting SQL Server, you may be able to reuse some code rather than write new code (mysql's version of SQL is not the same as SQl Server's version). Synching the two databases may be more complex than you think (differnt data types, etc.) and the data in the real database is not real-time whereas with the first alternative it is.
I'd prefer the separate database approach.
It's more secure.
PHP/Mysql hosting is widespread
You can pretty much achieve anything with the technologies available, it just depends on your skill and productivity with specific technologies and the availability of online help. Plus Microsoft stuff you tend to have to pay for whereas PHP/MySQL is totally free.
I've been searching for some time for a good solution to implement the idea of managing schema on an SQL Server Compact 3.5 database.
I know of several ways of managing schema on SQL Server Express, SQL Server Standard, SQL Server Enterprise, but the Compact Edition doesn't support the necessary tools required to use the same methodology.
Any suggestions/tips?
I should expand this to say that it is for 100+ clients with wrapperware software. As the system changes, I need to publish update scripts alongside the new binaries to the client. I was looking for a decent method by which to publish this without having to just hand the client a script file and say "Run this in SSMSE". Most clients are not capable of doing such a beast.
A buddy of mine disclosed a partial script on how to handle the SQL Server piece of my task, but never worked on Compact Edition. It looks like I'll be on my own for this.
What I think that I've decided to do, and it's going to need a "geek week" to accomplish, is to write some sort of a tool much like how WiX and NAnt works, so that I can just write an overzealous XML document to handle the work.
If I think that it is worthwhile, I'll publish it on CodePlex and/or The Code Project because I've used both sites a bit to gain better understanding of concepts for jobs I've done in the past, and I think it is probably worthwhile to give back a little.
Edit on 5/3/2010:
If someone is willing to "name" the project, I'll upload the dirty/nasty version that I've written for MS SQL to CodePlex so that maybe we can start hacking out a version of SQL Compact. Although, I think with the next revision of the initial application that I was planning, I'm going to be abandoning SQL Compact and just use XML Files for storage, as the software is being converted from an Installable package to being a Silverlight application. Silverlight just gives a better access strategy.
I am currently looking into Migrator.Net.
This allows you to write changes to your database, called migrations, directly in C#.
These migrations can contain everything from simple table additions/drops, column modifications, to complicated data update code.
When your application boots, it can verify what version the database is currently in and apply any migrations that are required to bring it up to date. All this is handled automatically. The code to run this update is as simple as:
Assembly asm = Assembly.Load("LocalModels.migration");
Migrator m = new Migrator("SqlServerCe", "Data Source=LocalModels.sdf", asm, false);
m.MigrateToLastVersion();
I am having a couple minor issues with the Compact support (it assumes the default schema is dbo). But I don't think it will be too difficult to fix them.
some random thoughts (not sure I can fully answer though)
the Microsoft Sync Framework is one option. I haven't had a chance to fully appreciate what it can do once you've deployed it after the initial first time (which seems to work fine). There's a MSDN site for it here
You can execute scripts on a mobile device, but not through something like SQL Management Studio, so in theory you could manage/maintain T-SQL scripts but the down side is that the T-SQL would be convoluted (to CE's supported statements) and I don't know a way to "automate" execution - but the Sync Framework might hold some answers..
If one of your key criteria is going to be working efficiently over a small pipe, the only real choice you have is to store a DB Schema Version (maybe somehow tied to the scripts checked into your CMS) and when an update is needed, the change scripts are sent over the wire and applied in order. You would probably want to keep a log in your DB as well of these scripts being applied so you can gracefully handle disconnects, reboots and other potentially nasty problems.
Is SQL Server Management Studio any use for you?
http://technet.microsoft.com/en-us/library/ms172933.aspx
Is it possible to use e.g. SQLite with PowerBuilder? I need an embedded open source database (no additional costs).
Like Bernard said, you'll need an ODBC driver, so as long as you're willing to go third party (if I understand the SQLite situation correctly), that should be no problem.
That said, if you have PowerBuilder, you have license to distribute the single-user SQL Anywhere run time engine. If no-cost is your only criteria, and you're only connecting locally, SQL Anywhere may be an option to evaluate. Not only is it an incredibly solid database, but there's a much larger base of documentation and experience connecting PowerBuilder to SQL Anywhere, so if you run into problems, you're more likely to get some help.
Good luck.
I don't believe that PowerBuilder contains a driver for native support to SQLite. But it definitely has a driver for ODBC, so that is always an option even if it isn't the most efficient one.
I used to use SQL Anywhere, but eventually ditched it for the reasons Joe Landau gave - can't change the schema using the distributable runtime engine.
I switched to Firebird, which has an embedded version, and that seems solid. The only issue is that the ODBC driver I'm using (Gemini), which seems to be the best one available, seems to have gone out of business. (I just checked - it seems to be available on other sites.) And you have to add the following to your PBODB*.INI file:
[Firebird]
PBSyntax='Firebird_SYNTAX'
PBNoCatalog='YES'
[Firebird_SYNTAX]
CreateTable='CREATE TABLE &TableName (::ColumnElement[::ColumnElement]...)'
ColumnElement='&ColumnName &DataType'
DropTable='DROP TABLE &TableName'
GetIdentity='Select gen_id(GEN_&TableName,0) from RDB$DATABASE'
I've been very happy with it. Using it for almost 2 years, with over 1,000 users, and no problems whatsoever. You can also easily switch to the Firebird server version if some users need that.
As noted, SQL Anywhere is available and solid. But it has a disadvantage--you can't change the schema using the run time engine. This makes it hard to, say, add a column to a db that you have distributed.
++ to the comments by DC on Firebird. One of the best free databases out there. I have used it for years for a PB application I sell to Law Firms.
Although I use the server version even if the target is a single workstation. Simplifies the deployment and the issue of adding workstations later if desired.
I use the standard Firebird ODBC driver at http://www.firebirdsql.org/index.php?op=files&id=odbc
There are two good GUI front database management tools that I hve used - IBOConsole and Flamerobin.