We are in the process of migrating an old VFP application into a .NET WPF application with SQL server.
During the process we still need to read/write to the DBF files to keep our business working properly.
To do this, we use the standard OLEDB adapter that is available. However, our sysadmin is asking if we have an alternative way to access the DBF files.
Having each user connect to the files is not the best option from a network/security perspective. Specially when connecting from home through a VPN.
I've already tried to move the connection to a single server by exposing the data through an API. But that was slowing down the application too much. In some situations we synchronise the data through background jobs (Hangfire implementation). But this can be time consuming to implement.
Has anybody used any other techniques to do something similar while migrating a VFP application?
OLEDB is still the best option. Within the application, you could impersonate a specific user that has access to files.
Also Sybase Advantage Server can connect and work with VFP data files. Local mode is (was) for free and server mode paid. You might try checking that too.
Locate data on single PC as server. Access via RDP - kludges available to support multiple connections. Increase security if needed by connecting over VPN - then RDP.
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I need your help to answer a question.
I coded a basic c# portable exe application that uses an Access Database on a server computer. On the network there are some client computers that runs this application and retrieve and store data via this database placed on the server computer in a shared folder. Every client coputer can access my database with this connection string:
#"Provider=Microsoft.ACE.OLEDB.12.0;Data Source =\\ANKFILESERVER1\aractakip\DatabaseAd.accdb
So far, there has been no problem. But as known, Access (Oledb) database has a limited capacity to save datas and since i'm worrying that someone change or delete my database files -authenticated for everyone- i decieded to use another database platform like postgresql.
My question is, if i install postgresql on the server computer and migrate my database tables, Are every client computers needed to install postgresql to access my database tables? If yes, what should be my connection string?
Thanks in advance.
You will need a client driver - like psqlODBC - installed on each computer that connects to PostgreSQL via MS Access, yes.
You can install psqlODBC separately, or using the main PostgreSQL installer. The separate psqlODBC-only installer is an msi that can be deployed over Active Directory, making management easier.
The connection options are covered in the psqlODBC documentation.
Microsoft Access is really written for the Microsoft JET / OLEDB engine, and to communicate with Microsoft SQL Server. It works with PostgreSQL, but it doesn't fully "understand" all PostgreSQL's features. It also does some things in totally non-SQL-standard ways that work on MS SQL but do not work on PostgreSQL. So it can be awkward to use MS Access with PostgreSQL due to things like Access not really supporting SEQUENCEs properly. Note, though, that I haven't used Access since Office 2008, so things may have improved.
I am tasked with creating a central Database for a small office to allow multiple computers to connect to a database using a C# program. I have already written the program and it currently connects with a database that is in the bin folder.
I am completely lost as to how to move on to creating a multi user environment. I searched all around SO and tried downloading Microsoft SQL Server, but I have no idea how I would set this up in the office and allow it to be accessed from multiple computers. Also, from the information I've gathered, Microsoft SQL Server needs to be running at all times to allow a connection -- this isn't a deal breaker, but is there any other methods that wouldn't need this? There isn't exactly a "main computer" in the office that is always running.
To run a centralized sql server database in your office you would at a minimum setup sql server on a "server". The server can be pretty simple unless you expect a heavy user load.
The server has to be on in order to allow connections.
Sql Server exists in a free version called Sql Server express, but it has limitations when it comes to scalability, so it's not meant for large systems.
You can download it and install it on your server in the office and connect to it through a connection string in your application.
You can also consider open source platforms like mySQl, but it would still require a central server.
Alternatively you can consider a hosted solution where you have a company host the database for you in their data center.
If you do not have the server computer in your office that will host the DBMS and allow others to connect to your DB using the web interface, try to use Windows Azure. This will cost you some money. Here you need to estimate what is cheaper for you: purchase a server or pay for the azure.
After much Google searching and at the risk of asking dumb questions, I could use some help. I’m developing a C# WinForms client application using ADO.NET to read/write data from a SQL Server 2012 database located on the Internet. That same application also needs to upload/download data files. The client application will only be used by a few employees (ever). The employees are all in different locations. The database is only about 20 MB. There will be about 100 data files totaling about 300 MB accessed individually on a periodic basis. SQL Server 2012 is running on a (non-virtual) Windows Server 2008 R2 machine which we have full control over. The client application will be running on Win-XP and Win-7 machines.
Priorities are 1. Internet security – keeping hackers out of the Windows Server machine and off the client/server communications. 2. Performance. 3. Simplicity. Corporate security and scalability are not issues. Also, performance is not that important if the solution is overlay complicated.
Two related questions I could really use help on:
Given the above priorities, what is the best way to communicate with the database? The only two options I’ve found are exclusively; a WCF service or directly through a VPN.
And again given the above priorities, what is the best way to upload/download data files? I’m sure there are many options for this using VPN, WCF, FTP; but I don’t know any specifics. Also, using a SQL Server 2012 FileTable looks promising but I’m not sure how that works over the web. Backup/restore plus being able to do a full-text search over the data would be nice features but not requirements.
I know what a VPN is but have never used one for these purposes. I know there are some security issues with PPTP, but we won’t be upgrading the XP machines for a while. I know what a WCF service is but have never written one. I also don’t know if SOAP or REST is better in this instance. I’ve built a FileTable in SQL Server, but I don’t know how to access the data remotely. I have decent knowledge of C#, ADO.NET, and SQL Server.
I realize these are big questions with subjective answers. Still, any ideas or a shove in the right direction would be greatly appreciated.
Keep it simple and use standard mechanisms. My recommendation is as follows:
Build a WCF service that is capable of performing the operations you want. You can build a SOAP or RESTful service. My general guidance here is to build a RESTful service because you're transferring files and this is much more integrated with REST. With SOAP you have some setting you're going to need to fiddle with to transfer large files.
Use SSL to secure the service, keep it simple. A VPN is an added layer of complexity and very likely not needed in this scenario. Further, it will only make the experience for the users less friendly.
I would not recommend using the FileTable in SQL Server 2012 for your needs. You own the server so when you send and receive files it will be much more straight forward to deal with the file system.
You can also build a simple forms authentication process that creates a session key for the user and passes it back. I'm not sure this is necessary, but if you need that extra layer, just make that one of the operations. Then that session key can then be passed into each method and validated before performing the operation. This will be safe because you're using SSL.
Here is a tutorial that will help walk you through building a RESTful WCF service, and it's fairly new.
My recommendation would be to deploy a VPN server to provide the security you are looking for. There are a number of good VPN servers available, and a Google search should provide a number of options at varying price points.
Once you have deployed the VPN server (and clients to all computers not on your local network that you would like to be able to access the database), you can use ADO.NET to access the database. ADO.NET will work seamlessly behind the VPN.
From the context of your question I am assuming that the files are stored in a file system outside of the database, and the database merely references the files. If this is the case, you could use any number of options for downloading the files, but FTP is a time-tested, easy-to-implement solution. There are others that may or may not work better in your situation (see here for a few options).
I created a C# application that uses .mdf database and it works perfectly on my PC.
Now i wanted to install that application on network PCs that can connect to a single database and use that data.
I tried changing the connection string in application with only changing file path, but it doesn't work. How can i use one PC as server and use program as client application that can connect over network. How do i set up SQL server on that PC, and should i do that? How is this done? I couldn't find any tutorial so far...
Could someone help me a bit.
I don't think you should be doing this, this is something that I once looked into myself. I once used a standard base unit for this same purpose and although it worked fine your not really supposed to do it.
You have to ask yourself how important the application is to the business. If its critical then this would be a real bad move for a couple of reasons :-
1) What happens if base unit hosting SQL Server dies? or is switched
off. Your unstuck.
2) You will only be able to schedule backups of the
SQL Server Database on the local hard disk . If the Disk dies then you
will lose everything.
When all is said and done, for the scenario that you are presenting, a MS Access database is probably a cleaner way to go. Access databases, albeit dated, can be hosted on a shared network space and can be accessed by multiple users. ADO.NET is nt too bad and you can still use LINQ with Data Tables etc.
What your looking into doing in your description wont really be fruitful unless your hosting the SQL Server on an Actual Server, as its designed for.
Some people suggest using using SQL Compact, but that itself is designed only to run from a local machine.
Hope this Helps.
#Milan: Go to the SQL Server configuration manager and enable TCP/IP service for SQL Server. As sql server uses TCP/IP for communication.
This link will help you.
http://kristofmattei.be/2010/06/21/enabling-sql-server-2008-r2-access-over-network/
I'm hoping someone can help me. I recently started the development of a windows form application connecting to a remote sql server database. I was happy enough developing it until a potential client queried if they would be able to buy the whole application but they do not want the application connecting to the db via the internet.
I predominantly develop websites using php/mysql but migrated to c# for this particular project. I'm familiar with sql but not sure what database I should be using if the client wishes to have the whole application on their own computer. I've considered providing the database install as a pre-requisite when publishing the app (although I'm currently not sure how to do that) but I'm having reservations whether that is suitable or could lead to more problems. I want to create an application that can install to a single computer and has little to no need for administration. Could someone advise the best way to approach the data storage in this instance.
Because you have already a SqlServer database operating on your remote site, the best path should be to use the LocalDB version of SqlServer Express 2012. See this link about deployment.
If you don't use stored procedures, views and triggers then also the SQL CE could be an option, but you will not have file binary compatibility and you should work on importing your schema and data.
SQL CE is a compact light weight way of going..
http://blogs.msdn.com/b/sqlservercompact/archive/2011/01/12/microsoft-sql-server-compact-4-0-is-available-for-download.aspx