I would to have the ability to connect to a SQLite database file, I am using a C# SQLite Library but due to Silverlight's permissions I can not make a connection to actually locate the file, Can anybody help with actually using the file to execute queries on to?
Thanks.
SQLite is an embedded database which means that only the process hosting it can use it and run queries against it. If you want to connect to a database on the server, you have to expose it through a service (SOAP, WCF, WCF RIA Services) or a REST endpoint.
Using SQLite with Silverlight only makes sense if you want to store files locally.
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I have a disk top application made by c# visual studio. My question is do I have to setup SQL server on each client to use my application? or there is another way to attach my database with my application and compress it as one and send to each client and those just extract that file and use the application correctly?
On a real scenario, your database should be placed on a remote server and the clients should only access the database through your API (that will need to support authentication or any other identity based systems).
If your application only needs to store some local information (relevant only for your client app), then you can just use LocalDB or AppSettings, depending on your data structure.
Otherwise, if your application contains more complex features, then you will need an API and a remote DB managed only by you.
To conclude, you only need to setup Sql Server once, when you want to create the design of it (tables, columns, links). The clients will only have to connect to it and pull their data. And this task can be done without installing SqlServer. This link shows you that you only need System. Data assembly to connect to a Sql Server DB.
Yes you need to instal SQL server on each machine or if you go for LocalDB then also u need to instal SQL server engine ,and you have a better option u need to buy sqlserver from AZURE (it's free for one month try if want click here AZURE)
I'm working on a project and I need to connect to MS Access Database. The problem is that I'm using a pretty new platform , I'm using Visual Studio 2015 Xamarin and I'm developing to android with c# (thought this platform).
I already have a project with this Database using aspx and i need to connect the android application to this Database .
I could not find any answer for it , probably cause it's new .
Thanks for helping.
The problem is not related only to Xamarin or MS Access.
Everytime you want to use the same database in different applications (in your case a website and mobile apps), it is better to create a new layer (WCF Service or REST API) in order to access the same database on the server. This is more flexible and would be the right thing in your case.
Without moving the architecture to the next Level, you will always have such problems when mixing old and new technologies together.
If you just want to finish this quickly for school and use the database only on the device, then there is no way to use the MS Access database with xamarin. I recommend using SQL lite for this and there are lots of examples for that:
https://developer.xamarin.com/recipes/android/data/databases/sqlite/
It not clear if the database is to run “local” on the android, or you just wishing to connect to some web service that holds the database?
If you needing a local database to run 100% stand-alone on the Android device, then Access is not supported. Your best bet for a local database would thus be SQLite.
Perhaps you don’t need nor want a local data store. In this case if the Access database is on the server, then you would be forced to write some kind of web service to “interact” with your Android software and the web server (this would not be a "general" interface to the database, but a set of web services that you expose on the web site - this assumes you thus have control and are able to write software and implement a web service on the web site. So in this case some kind of “direct” connection to the Access database is not possible.
You could again certainly DIRECTLY connect to a server based database like SQL server – but this would assume the web hosting allows external ODBC connections to the database (often they don’t allow this, but some do).
So not clear is if you need a local database running on the Android that can THEN connect to some web or server based system, or you simply want the android to connect via the internet to some database hosted on some server and the Android device does not have a local database at all.
Regardless of the location of MSAccess, you cannot "connect" to a non server database like Access. So the question remains as to "where" you want this database to be used, and ALSO if you need a local data store on the Android device or not.
I'm working on a program that will work very nicely with a database structure and using mysql. I could easy do this with a common server and common database. However I'm looking for a way to have my client(s) use the program on an offline machine without having to install any database managing software.
Basically I want the installation to set up the necessary tables on their machine and have them fill in the database with information relevant to them. Before I start though I wanted to know if this was possible to connect to and manage a database through a C# application with out installing sql software.
You could consider using SQL Server Compact Edition.
SQLite is another option.
Both of these can be deployed with your application and need no separate configuration.
Yes. It is possible. How to do it exactly depends on the database connection approach you're using. For example, this approach shows how to use DataReaders. That's a very old approach. Modern approaches are recommended to use LINQ to SQL, which can be configured to access remotely by setting up a DataContext to point to an external resource.
Basically, wherever you can define a connection string to connect to a DB, you can make that string point locally or externally. An external resource must obviously be available through some URL in order to connect, of course.
You can not connect to a mysql database without installing mysql.
However you can use in process database like sqlite or Compact SQL. They are not traditional server, but rather a library that keeps the database in a local file.
I work on a Joomla web site, installed on a MySQL database and running on IIS7. It's all working fine.
I now need to add functionality that lets (Joomla-)registered users change some configuration data. Though I haven't done this yet, it looks straightforward enough to do with Joomla. The data is private so all external access will be done through HTTPS.
I also need an existing c# program, running on another machine, to read that configuration data. Sure enough, this data access needs to be as fast as possible. The data will be small (and filtered by query), but the latency should be kept to a minimum. A short-term, client-side cache (less than a minute, in case a user updates his configuration data) seems like a good idea.
I have done practically zero database/asp programming so far, so what's the best way of doing that last step? Should the c# program access the database 'directly' (using what? LINQ?) or setup some sort of Facade (SOAP?) service? If a service should be used, should it be done through Joomla or with ASP on IIS?
Thanks
I ended up using a WCF service façade written in c# that returns the data from the database. The service only exposes a couple of functions that query parameters as arguments. The SQL queries are not exposed, nor is the database connection string. The WCF service uses the mysql connector/net 6.3.1 to talk to mysql. The WCF service is accessible only over https, and requires a username & password.
I am designing a Windows application in C# which when run for the first time creates a local database (SQLite) and the data (around 200 MB or even more) to this is feed as a data stream from a remote server based on the criteria specified by the user.
Currently I have planned to access the database server directly from the application.
Questions:
Is it a good idea to use the database server directly from the application as the server manages connections automatically and I save time in developing a TCP/IP interface.
What can be the second option? Providing a TCP/IP server or interface (Isn't it time consuming to write it?).
As the data is large should I use compression?
With WCF you can avoid the cost of writing TCP/IP code and have a standalone server or a web service hosted on IIS. Moreover, compression can be added without code change.
You have to try with and without compression. The compression rate highly depends on the data and compression time can also be an issue.
Without going into large detail I can say you can use ASP.NET C# (You can choose any .NET language) and you can send and receive data using POST.
Why would you need compression? You are only sending results? If it is big you can use an existing library. I have used sevenzipsharp in the past without much issue.
Edit: There may be an option on the server to gzip output data so you may not need to use anything.
Assuming that your intention is to pull down a subset of the data on the server dependent on client queries for local storage then for reasons of security and control you probably ought to be looking at using web services rather than exposing your database directly to the internet.
There are a large number of options for creating services - WCF being the principal method for new .NET applications and straightforward to implement at both server and client ends - in this case I'd also probably take a look at ADO.NET Data Services as providing a shortcut to a rich set of services.
It is usually best to use ADO.NET or LINQ to SQL (Entity Framework) to connect to your Database directly unless the User is going to be disconnected while using the application.
If you are going to have the user disconnect then continue using SQLite or you can use ADO.NET which can save an XML file of the data and access it like a Table from the users machine without the additional dependence of SQLite.
I would not use compression because C# does not have a built-in library for it and would require an additional dependency.
Try to just use the .NET Framework without additional DLL's and you will have a more flexible application that is easier to install and maintain.
ADO/Entity Framework - http://msdn.microsoft.com/en-us/library/h43ks021.aspx