Database on a separate server - backup .bak - c#

I have a database on the server shared on the local network. I would like to write an application that backs up the database from this server, but not on the server, but on the computer from which I started this application. That is, for a better understanding:
The database is on some Windows Server server. I have a laptop that is connected to the same network and has access to a database. On this laptop, I start the app, connect to the database and the .bak file is saved to the laptop, not the server.
At the moment I wrote only so much and unfortunately it doesn't work for me:
private static void CreateDatabaseBackup(string connectionString, string databaseName, string backupFilePath)
{
SqlConnection connection = new SqlConnection(connectionString);
SqlCommand backupCommand = connection.CreateCommand();
backupCommand.CommandText = $"BACKUP DATABASE {databaseName} TO DISK = '{backupFilePath}'";
connection.Open();
backupCommand.ExecuteNonQuery();
connection.Close();
}
This throws me an exception:
System.Data.SqlClient.SqlException: „Cannot open backup device 'C:\Backup\backup.bak'. Operating system error 3(The system cannot find the path specified.).
BACKUP DATABASE is terminating abnormally.”
Probably because of the fact that it is trying to save the file to the server's disk, and it does not have the path specified in the variable backupFilePath
I would like .bak to be saved to the disk of the device firing the application.
How to approach this problem?

Related

Backup a remote SQL Server database

I want to backup my remote SQL Server database onto the local computer.
So far I've tried:
using (SqlConnection defaultSqlConnection = new SqlConnection(Constants.Database_Constants.GetConnectionStringFromProfile(Constants.Profiles.Staging)))
{
string pathDatabase = System.IO.Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().Location) + "\\backup_production_database"+DateTime.UtcNow.ToString("d_MMM_yyyy_HH_mm_ss", CultureInfo.InvariantCulture)+".bak";
WriteLine("The backup will be stored in " + pathDatabase);
string backupDb = "BACKUP DATABASE DB_Staging TO DISK = '" + pathDatabase+ "' WITH INIT, COMPRESSION";
File.Create(pathDatabase);
using (SqlCommand backupCommand = new SqlCommand(backupDb, defaultSqlConnection))
{
defaultSqlConnection.Open();
backupCommand.ExecuteNonQuery();
}
}
But I get this error :
Cannot open backup device 'XXXX\bin\Debug\backup_production_database22_Mar_2017_08_04_42.bak'.
Operating system error 3(The system cannot find the path specified.).
BACKUP DATABASE is terminating abnormally.
I know that I could generate a script using SQL Server Management Studio but it doesn't help me. I want to backup my database in a powershell script automatically without having to go manually into SQL Server Management Studio
You cannot create a directly backup from a remote server to a local disk.
Please look this link.

Publish C# application with SQL Server database

My application does basic CRUD operations over an external .mdf file. The database file is created separately in SSMS. On my PC, everything works perfectly fine. When I install it on someone else's computer, it refuses to connect to the database. The other PC also has the same database at the exact same location.
The connection string I am using is (in app.config):
conString=Data Source =.\sqlexpress; Initial Catalog = dbName;
Integrated Security = True; Pooling = False
In my code:
dbConnection = new SqlConnection(Settings.Default.conString);
The other PC has SQL Server installed as well. Tried going through almost all the results but almost all of them suggest either
Adding the existing database with the project. I can't seem to do that because when I try that I get an error:
permission denied
I can't rewrite the whole code with a service based database pre-attached to it.

Connect PC to SQLite db located in windows ce storage

I have a SQLite database file in my PC. I have an offline application on my Windows CE. This app gets data from this file and updates them. The process is here:
1- initialize SQLite db file (in PC)
2- Copy db file to windows CE storage (in PC)
3- Some process on data (in Windows CE)
4- Copy db file to PC (in order to access the data) (in PC)
5- Do main app processes (in PC)
After a while the db records become large. I used indices and vacuum command on db and the problem solved.
Again after a while the db records become huge. Now copying the file takes long time. I want to remove steps 2 and 4 in order to speed up Get/Send events in PC app.
Connection string is my problem. Here is my code:
private string ConnectionString_SQLite = "";
public SQLite_()
{
string Data_Source_SQLite = `#"\\\Asset\System.db"`;
ConnectionString_SQLite = "Data Source=" + Data_Source_SQLite + ";Version=3;";
}
I tested these data sources in connection string:
#"\Asset\System.db"
#"\\Asset\System.db"
#"\\\Asset\System.db"
#"Computer\POINTMOBILE PM60\\\Asset\System.db" (copied from windows explorer address bar)
Is there anyway to access the file located in path \\Asset\?

OS error 3 when backing up database

It is a follow-up question to my previous question in the same forum.
I would like to take a backup of my SQL Server database. Here is the code, for the backup in C#.
userConn = new SqlConnection(userdatabase);
userConn.Open();
string UserString;
UserString = "BACKUP DATABASE #DBName TO DISK = #FilePath";
String destPath = DestDirectory + "\\UserDataTable.bak";
SqlCommand cmd = new SqlCommand(UserString, userConn);
cmd.Parameters.AddWithValue("#dbName", userConn.Database);
cmd.Parameters.AddWithValue("#FilePath", destPath);
cmd.ExecuteNonQuery();
cmd.Dispose();
However, it throws an SQLException,
"Cannot open backup device
'D:\BookKeeping\Database\11_01_2013_21_15\Database\UserDataTable.bak'.
Operating system error 3(failed to retrieve text for this error.
Reason: 15105). BACKUP DATABASE is terminating abnormally."
Any Idea, what could be wrong ?
Thanks a lot for your time and your help.
"Operating system error 3" means that the directory was not found. SQL will not create the backup directory for you; you have to manually create it before running the backup command.
Make sure your SqlServer and the location where you want to create a backup is the same system. If you are using sqlServer remotely(Not located in your system) then you can not create a backup in your machine or you can not restore the database taking a .bak from your machine also.

Having trouble connecting C# executable to database file on remote computer

Using VC# I've created a staff management app that, upon its first run, is expected to query the user for the path to a (.mdf) database which will reside on a remote computer. A resulting path may be something like
string dbPath = #"P:\remoteComputer\public\StaffTool\ExamplePersonnelDatabase.mdf";
Then I'm placing this string into a connection string template as so:
string dbConnectTemplate = #"Data Source=.\SQLEXPRESS;AttachDbFilename={0};Integrated Security=True;Connect Timeout=30;User Instance=True";
string dbConnectionString = String.Format(dbConnectionTemplate,dbPath);
Then I'm attempting to connect to the database LINQ to SQL style
ManagementDBDataContext db = new ManagementDBDataContext(
dbConnectionString);
At this point, an error pop's up stating that
The file "P:\remoteComputer\public\StaffTool\ExamplePersonnelDatabase.mdf" is on a network path that is not supported for database files.
An attempt to attach an auto-named database for file P:\remoteComputer\public\StaffTool\ExamplePersonnelDatabase.mdf failed. A database with the same name exists, or specified file cannot be opened, or it is located on UNC share.
As I am relatively new to databases, I completely do not understand this message. And obviously, the file is not on a UNC share.
Any ideas?
Jim Lamb recommended that I connect to an instance of SQL server running remotely. Considering that I'm using LINQ to SQL, what refactoring do I have to do to make this happen? Other ideas still welcome - especially "push this button and everything will work" solutions.
Another clue: A coworker said that there used to be some way to work through Control Panel->Administrative Tools->Data Sources(ODBC) so that a remote database could be viewed from my computer as if it was local. The coworker didn't know any more details besides this.
You are attempting to connect to a database file on another machine over a network connection, which isn't supported by SQL Express. You'll need to make a local copy and attach to that, or connect to an instance of SQL that's running on the same machine as the MDF file.

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