I am a newbie to SQL Server and .net. Please let me know if my question is not clear before down voting.
I am working on a Windows application with C#. I should give option to users to connect to a .mdf file on a network drive. On my machine, I have Windows and SQL Server authentication. Users have SQL authentication hence I should use userid and pwd. Myself and users work on that network drive, read/write/modify. We pretty much share documents, add and delete docs from network drive.
Here is the designer
I will choose the SQL Server database .mdf file which is located in network drive and then do test connection. For Test Connection this is the code
string sTemp = System.Configuration.ConfigurationManager.AppSettings["connectionStringShare"];
string connectionString = sTemp.Replace("{AppDir}", txtDB.Text.Trim());
using (SqlConnection objSqlConnection = new SqlConnection(connectionString))
{
try
{
objSqlConnection.Open();
objSqlConnection.Close();
MessageBox.Show("Connection is successfull");
}
catch (Exception ex)
{
MessageBox.Show("Error : " + ex.Message.ToString());
}
}
This is the connection string
<add key="connectionStringShare"
value="Data Source=.\SQLEXPRESS;Initial Catalog=TableSQLExpress;AttachDBFilename={AppDir};Integrated Security=SSPI;user id=sa;password=pwd;" />
Here is the error message I got
Directory lookup for the file "S:\zrep\TableSQLExpress.mdf" failed with the operating system error 3(The system cannot find the path specified.).
Cannot attach the file 'S:\zrep\TableSQLExpress.mdf' as database 'TableSQLExpress'.
I changed connection string and tried also tired using windows authentication. No luck. Let me know if I need to provide any additional details. Since I am newbie to this field please give me detailed answer. I am glad to find this group. Thanks for everyone who looked into this.
When you use server-based SQL Server (i.e. Microsoft SQL Server Express) you are unable to share database file via network drive, it is by design. Even if you override default SQL Server behavior with a switch and enable UNC paths for databases, your data will be corrupted by multiple server instances trying to use single database MDF file. If you need to host database in serverless environment (using only a network drive), you may opt to Microsoft SQL Server Compact (SQL Server CE) edition. But be aware that in such case only one user will be able to access database file at the same time (exclusive locking -> low performance). Plus SQL Server CE does not have stored procs.
Related
I have a problem I need to solve, but not know how exactly. I have a WinForms application (C#) which connects to an online MySQL server - no problem there. In this application I have an option to make database backups (basically I dump this database to a local file on a computer).
I would like to locally "open" this backup on client's computer (to check some old data) - I don't want to make database restore on my server, because database must still be in use for other users. I want to make clean install of MySQL on a local computer and connect to it trough localhost (like I do for testing ), but I do not have physical access to that computer. I can send MySQL installer to my client, but how to go about automatically creating user with password and database from my dump file?
I know how to create a new database if it doesn't exist, but how to do it if it's clean install of MySQL server - no user and password yet.
string connStr = "server=localhost;user=root;port=3306;password=????;";
using (var conn = new MySqlConnection(connStr))
using (var cmd = conn.CreateCommand())
{
conn.Open();
cmd.CommandText = "CREATE DATABASE IF NOT EXISTS `hello`;";
cmd.ExecuteNonQuery();
}
Any help and direction is appreciated.
Regards!
I don't know whether I understand your problem. However,if you install a new Mysql，you can use root user through no database.
Anyway, one thing you need to know,Connect database must has user and password for mysql or sqlserver.
You may need to be more concise description of your problem.
I have created an application using Entity Framework 6 code-first, in ASP.NET MVC 5, and am bin deploying it to my server. Everything works fine, except for the operations/controller actions that involve database usage.
I am uploading the once-generated database file from my computer to the App_Data folder of the server.
Upon deploying, I changed the connection string in my web.config file from:
connectionString="Data Source=(LocalDb)\v11.0;AttachDbFilename=|DataDirectory|\aspnet-NERC_Main-20160104065223.mdf;Initial Catalog=aspnet-NERC_Main-20160104065223;Integrated Security=True"
to
connectionString="Data Source=.;AttachDbFilename=|DataDirectory|\aspnet-NERC_Main-20160104065223.mdf;Initial Catalog=aspnet-NERC_Main-20160104065223;Database=aspnet-NERC_Main-20160104065223.mdf;Trusted_Connection=Yes;Integrated Security=True;"
which throws an error of
CREATE DATABASE permission denied in database 'master'.
A probable cause of this is because the present database file is not being attached, and the entity framework is trying to generate a new database in some other, restricted directory.
I read that the AttachDbFileName is valid for SQL Server Express instances only, which in my case doesn't exist.
How can I modify the connection string so that my current, already uploaded database is utilized.
Note:
The remote server has a full installation of SQL Server 2008 R2. The server does not support user instances. My database is not password protected, and hence I've set the Integrated Security property value to True. I'll provide any other information if required.
If you have a full version of SQL Server, you cannot just use AttachDbFileName. Instead, you need to copy the .mdf (and .ldf) to the SQL Server data file location and then you need to attach the database in SQL Server Management Studio to the server instance.
From that point on, you can reference that database in your connection string using the server name, and the logical database name - something like this:
Server=.;Database=aspnet-NERC_Main-20160104065223;Integrated Security=True;
Depending on your database setup, you may or may not be able to use the Integrated Security - maybe you'll need to have a specific SQL Server login and specify that login (and its password) in your connection string instead:
Server=.;Database=aspnet-NERC_Main-20160104065223;User ID=YourUserName;Password=YourPassword
See this site here for a ton of sample of how to build valid connection strings for SQL Server.
I'm very new to SQL and made a small program where a user can input some data, click submit and the data is then stored in a table in the database.
I know want to move the application onto a friends computer, which i'm assuming has no SQL software installed, what would be the easiest way to do this, when obviously the connection string is unique to my computer and the database is stored on my computer.
You will have to install SQL Server on their machine first and foremost. Once this is done, you can obtain a relevant connection string. Note, for the 'Server name' part of the connection string, if you are using SQL Express, instead of using 'localhost', or the name of the server instance (i.e. 'MyMachine'), you would use 'localhost\SQLEXPRESS'/'MyMachine\SQLEXPRESS'.
After setting up the SQL Server instance on the new machine, to copy the required database, first detach the database to avoid any corruption. Now you are free to merely copy the file from your machine to theirs and go through the usual attachment process using SQL Server Management Studio (SQLMS).
I hope this helps.
You can use SQL CE or other file databases. On this way you need to install SQL CE(you can include SQl CE installer into your program installer) on target computer and after that you can easy copy db-file from you computer to target computer.
Also, you can use relative path to db-file from your exe file instead of fixed connection string:
string dbDirPath=Path.Combine(AppDomain.CurrentDomain.BaseDirectory,"DB" );
private const string CONN_STR_TEMPLATE = "Data Source={0};Persist Security Info=False;";
string dbFilePath = Path.Combine(dbDirPath, "my.sdf");
_connStr =String.Format(CONN_STR_TEMPLATE,dbFilePath);
You cannot simply copy your database since SQL Server database is NOT a standalone database as SQL Compact edition/MS Access.
You may configure your router to remote access SQL Server instance over the Internet by forwarding the port
Accessing SQL Server Instance through NAT
I write a win app,and i create my database on the server by codes.now every client on local network can't login to my database and this error occured
:"cannot open database "test" requested by the login.the login failed for user "farzane".
the connectionstring for to make my database is:
ConnectionString=#"Data Source=SERVER\SQLEXPRESS;Initial Catalog=master;Integrated security=SSPI;Persist Security Info=False";
and it's my connection string for open my database:
ConnectionString=#"Data Source=SERVER\SQLEXPRESS;Initial Catalog=test;Integrated security=SSPI;Persist Security Info=False";
how can give permission for logining to my database to any client with codes???
thanks in advance for any help.
I would check two things here:
Ensure that your SQL Express install allows remote connections. (Simple to check using SQL Server Studio Manager).
You are using trusted authentication in your connection string. You have to explicitly give users on your domain access on the database. You will have to this in SQL Server.
are you using a domain for the network ?
if yes then make sure that the user name has access to the SQL server
if you're using a workgroup then it won't work... just create a user on the sql server and use the sql server auth at the server and connection string
Points i concluded:
First of all the users who are going to create the database , must be authorized to use master database. So ask your admin to allow permission to farzanne.
If you(farzanne) are admin, set farzanne to create databases permission to true. Or the other users that might create dbs. Also, if you allow all users then it will be difficult to handle, your application, so be alert.
What is the need of the dynamically createing database from application. Is this a part of setup or deployment or you are creating an isolated space that is different user different database.
Sorry for the confusing name, I did not know of better one. There is a network with SQL 2005 server. I am provided with the windows account information to this computer so I can use remote desktop or map its drives. The SQL uses trusted connection. I am thinking whether I can connect remotely only to the SQL server? Thanks
This is based on my experience with SQL Server, but may not be entirely complete in scope.
SQL Server Manager will let you connect to the server instance with windows credentials, but to access the database tables you will need to create a login within SQL Server. Using SQL Server Manager, you can do this under the Security folder of the hierarchy of objects in the left column.
Next you will need to create a database (if one doesn't already exist that you are interested in using) and in that database's Security folder, create a user that corresponds to the login. When doing this you will also need to assign the permissions of the user (select, insert, delete, etc.).
Once that is complete, you can access the server anywhere on the network with the appropriate credentials, but you will need to make sure that there are no blocked ports, etc. from a network perspective.
In C# the statement to create a new connection looks like this:
SqlConnection conn = new SqlConnection("user id = username; " +
"password = secret; " +
"server = servername\sqlexpress; " +
"database = databasename; " +
"connection timeout = 30");
Hope that helps.