connect to .mdf file in vs2010 , wpf application - c#

I am using VS2010 , and I built a .mdf file using SQL server 2008
I want to use this database file in my wpf application so that I can add rows to it and delete rows from it
the problem is , I can't access this file , and all the insertion and deleting is actually hapening to the datacontexct i created .
I used myDataContexct.Submitchanges() but it didn't work either
I tried to add a connection string when I define the datacontexct that holds the url of my .mdf file and this it gave me a runtime error when trying to access this file and the error messege says :
An attempt to attach an auto-named database for file Trial.mdf failed. A database with the same name exists, or specified file cannot be opened, or it is located on UNC share.
please help me because I searched alot but I couldn't find any help

If the application is not going to be installed in a manner that many clients are accessing the same server, you would want to consider using SQL Server Compact Edition.
Are you sure the connection string in your app.config refers to the local mdf file? perhaps it refers to the server instance?
What technology do you use, is it LinqToSql or Entity Framework (I think you have t call SaveChanges, not AcceptChanges)?
If you do intend to access the server instance, then the problem seems to be a security restriction.
Please add more details on statement no. 1, and I'll write further info.

Related

Local DB in Visual Studio 2015

After a few years, I have returned to writing in C# and I am really struggling here - I would like to have my app to have a local SQL database. I have added Service-based database and "Database1.mdf" was added to my project. I created a table and added some data just to see if it is working but I cannot connect to it. I tried numerous connection strings with no success (Server not accessible).
Do I need to run something else in the background? I thought that I might have a local database and with .NET client I can access it, and I hoped it would work whenever I bring my application (also not requiring any SQL server running). Is that wrong?
If you don't require any SQL server, take a look at SQLite. This is lite SQL database engine. Database is just one file. C# has a great library to SQLite on NuGet: https://www.nuget.org/profiles/mistachkin
SQLite is widely used, event in Android (as a native db engine).
here is what i use to connect. it appears as a Data Connection in Server Explorer.
string con2 = #"Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=" + Application.StartupPath + "\\jobfile_2017.mdf;Integrated Security=True;Connect Timeout=30";
when i first started working with these, i used this source 1
it works on PC's that i have nothing installed (not even office) but as i said i'd be interested to know of any shortcomings of this method
I experiencing same problem and decided to move mdf file to static c:\db directory. Connection string was changed to incorporate new file location (AttachDbFile).
But AttachDbFile has some issues also (by some reason one table in db is inaccesible and error is access denied).
So I decided to move to Sqlite. LocalDb has many issues to work with. I read good note to resolve problem: in command line stop/remove/start name of instance. But it nuissance.
Wish you good luck to work with these db files.

Error in installing c# application in database

I have a windows application in C#, my connection string is:
and my database is in SQL Server 2008 R2.
but when I installed my program I receive This error:
Please help me I don't know how to solve this
As I guessed, you are (attaching is) creating a new database.
You are facing this problem because there is already a database in that server with the same Db name and primary file name. This is probably (mostly) due to adding the Db twice.
Please open SQL-Server Management Studio, and check the already existing Db of name IcuProject. If it's the same Db that you wanted to attach, then skip attaching part or delete the current db from server and try attaching it again.
As a best practice, if you are attaching a db thru application, then make sure that no db with same name already exists in the server. or best, ask user to enter a Db name so that you won't get a name conflict.

Showing error while back up the database in sql server

I am facing some error while i am trying to back up my database in sql server R2.
it is showing the following error:
TITLE: Microsoft SQL Server Management Studio
Restore failed for Server 'Ironhide\SQLEXPRESS'. (Microsoft.SqlServer.SmoExtended)
ADDITIONAL INFORMATION:
System.Data.SqlClient.SqlError: The media set has 2 media families but only 1 are provided. All members must be provided. (Microsoft.SqlServer.Smo)
This i commonly a problem with how the database backup was taken, it looks like when the backup was created it was split into two files, you wont be able to restore it unless you have both those files. Try creating the backup again but when you do the backup insure that you only have one file in the destination section.
This question has been already asked in SO: Any other solutions for SQL's “The media set has 2 media families but only 1 are provided. All members must be provided.” error?
Anyway, your backup set was splitted in two files, but you're trying to restore the data from just only one backup file.
One solution is to backup your data in just one file and repeat the restore process. The other one is to provide both backup files and try to restore again the data. In this way, SQL Server won't warn you again with that error.
The Microsoft Project Manager for SQL Backup explains here the error.

Firebird 1.5 / Asp net VS 2010 (legacy database .CDB extension)

I have an old system which generated me a database in .CDB extension (i run on Firebird-1.5.6.5026-0-Win32) and i can access this database in IBExpert to query and stuff. But i need to write an application in .NET (VS 2010 4.0 framaework) so i can read this database and access some of the data to insert into a table inside SQLServer.
I tried many things, changed the server version and other things but i now all i get is ''Cannot find fbembed.dll'' exception error while trying to open the connection. My FB server doesnt have this file since he uses the 'fbclient.dll' already.
Any thoughts on how to connect my application to this .CDB database?
(this firebird version is the same that the legacy system is running, so i used the 1.7RC firebird .net provider within this server)
The connection string used is:
<add name="FirebirdConnectionString" connectionString="User=SYSDBA;Password=masterkey;
Database=localhost:C:\temp\BD\E‌​CLECTIC.CDB;DataSource=localhost;Port=3051;
Dialect=3;Charset=NONE;Role=;Connectio‌​n lifetime=15; Pooling=false;
MinPoolSize=0; MaxPoolSize=50; Packet Size=8192; ServerType=1;"
providerName="FirebirdSql.Data.FirebirdClient"/>
Unless you really want to use Firebird embedded (which you don't as you also specify localhost), you should not specify ServerType=1, but either leave it out entirely or set ServerType=0.
As to your other problem you mention in the comments, I suggest you check if this solves it and otherwise create a new question with more information.

I want to run C# program without changing SQL Server instance or without changing SQL Server installed PC name

I have C# application which uses SQL Server R2 as its database. That database is on a separate PC by the name of SERVER. SQL Server's instance name also server.
My windows application uses DataSet to communicate with the database. Now my SQL installed PC name is change to another name, ex SERVERHP. Now all my coding works want to change my connection string. Are there any other easy way to do it ?
I am to tried to edit hosts file, but it does not work for me.
This is my coding style (http://goo.gl/FQrkp). I am using DataSet with DataAdapter with IDE designers.
I have 100 ~ 150 forms. Now I cannot compile all codings. I want to easy method to connect that SQL Server database.
I want to have a way to hide the change of the hostname of the computer
You have a couple of options:
Globally replace all server names with IP address in connection strings in the app
Globally replace all server names with the new server name in the app
Add a CNAME record to the DNS table on the server (assuming of course you're in the same network, which you are if you're using computer names)
Add an entry to the LMHOSTS file (you can add as many names as you'd like that point to the same IP)
As I understand, it is SqlConnection used to connect to database, or something like that. Why don't you use SqlConnectionStringBuilder? Then you can dinamically construct connection string you need. Also, to get list of servers, you can use SqlDataSourceEnumerator, from namespace System.Data.Sql.
It sounds like you want to have a way to hide the change of the hostname of the computer (Server/Desktop/Virtualized instance of Windows, whatever) that is running your SQL Server.
This isn't my area of expertise, but I can't think of a way to do it that only involves your application code and just the computer.
If you control the local DNS you can create a CNAME entry with the old name that "points" at the new one. Depending on how your connection strings are stored, you might have to edit them or you might not. But you won't have to worry about the location of your SQL Server changing again because you can always edit your CNAME to point at the new location.
Note for the future - not your current problem: If you continue to use MS SQL Server in particular you'll want to be careful about moving it to a computer where it isn't the default instance because then you need to put the instance name in the connection string as well, which might force you to edit all of your application web.configs and app.configs again.
Are you using Visual Studio 2012 with your development efforts? I ran into a conflict with the mini SQL db VS installs (Using Premium version) and had to modify the ConnectionStrings section of my Machine.config file to point to my SQL database. For whatever reason, VS will write references to the mini db in the Machine.Config file (for whatever version of .Net you are leveraging) throwing potetial conflicts.
The file can be found in %systemroot%\Microsoft.Net\Framework64\dot net version\Config
If you're using an x86 processor the Framework64 folder is just called 'Framework'.

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