How to execute an .SQL script file using c#

Question

I'm sure this question has been answered already, however I was unable to find an answer using the search tool.

Using c# I'd like to run a .sql file. The sql file contains multiple sql statements, some of which are broken over multiple lines. I tried reading in the file and tried executing the file using ODP.NET ... however I don't think ExecuteNonQuery is really designed to do this.

So I tried using sqlplus via spawning a process ... however unless I spawned the process with UseShellExecute set to true sqlplus would hang and never exit. Here's the code that DOESN'T WORK.

Process p = new Process();
p.StartInfo.UseShellExecute = false;
p.StartInfo.RedirectStandardOutput = true;
p.StartInfo.FileName = "sqlplus";
p.StartInfo.Arguments = string.Format("xx/xx@{0} @{1}", in_database, s);
p.StartInfo.CreateNoWindow = true;

bool started = p.Start();
p.WaitForExit();

WaitForExit never returns .... Unless I set UseShellExecute to true. A side effect of UseShellExecute is that you can no capture the redirected output.

Answer 1

Using EntityFramework, you can go with a solution like this. I use this code to initialize e2e tests. De prevent sql injection attacks, make sure not to generate this script based on user input or use command parameters for this (see overload of ExecuteSqlCommand that accepts parameters).

public static void ExecuteSqlScript(string sqlScript)
{
    using (MyEntities dataModel = new MyEntities())
    {
        // split script on GO commands
        IEnumerable<string> commands = 
            Regex.Split(
                sqlScript, 
                @"^\s*GO\s*$",
                RegexOptions.Multiline | RegexOptions.IgnoreCase);

        foreach (string command in commands)
        {
            if (command.Trim() != string.Empty)
            {
                dataModel.Database.ExecuteSqlCommand(command);
            }
        }              
    }
}

Answer 2

There are two points to considerate.

1) This source code worked for me:

private static string Execute(string credentials, string scriptDir, string scriptFilename)
{ 
  Process process = new Process();
  process.StartInfo.UseShellExecute = false;
  process.StartInfo.WorkingDirectory = scriptDir;
  process.StartInfo.RedirectStandardOutput = true;
  process.StartInfo.FileName = "sqlplus";
  process.StartInfo.Arguments = string.Format("{0} @{1}", credentials, scriptFilename);
  process.StartInfo.CreateNoWindow = true;

  process.Start();
  string output = process.StandardOutput.ReadToEnd();
  process.WaitForExit();

  return output;
}

I set the working directory to the script directory, so that sub scripts within the script also work.

Call it e.g. as Execute("usr/pwd@service", "c:\myscripts", "script.sql")

2) You have to finalize your SQL script with the statement EXIT;

Answer 3

Put the command to execute the sql script into a batch file then run the below code

string batchFileName = @"c:\batosql.bat";
string sqlFileName = @"c:\MySqlScripts.sql";
Process proc = new Process();
proc.StartInfo.FileName = batchFileName;
proc.StartInfo.Arguments = sqlFileName;
proc.StartInfo.WindowStyle = ProcessWindowStyle.Hidden;
proc.StartInfo.ErrorDialog = false;
proc.StartInfo.WorkingDirectory = Path.GetDirectoryName(batchFileName);
proc.Start();
proc.WaitForExit();
if ( proc.ExitCode!= 0 )

in the batch file write something like this (sample for sql server)

osql -E -i %1

Answer 4

I managed to work out the answer by reading the manual :)

This extract from the MSDN

The code example avoids a deadlock condition by calling p.StandardOutput.ReadToEnd before p.WaitForExit. A deadlock condition can result if the parent process calls p.WaitForExit before p.StandardOutput.ReadToEnd and the child process writes enough text to fill the redirected stream. The parent process would wait indefinitely for the child process to exit. The child process would wait indefinitely for the parent to read from the full StandardOutput stream.

There is a similar issue when you read all text from both the standard output and standard error streams. For example, the following C# code performs a read operation on both streams.

Turns the code into this;

Process p = new Process();
p.StartInfo.UseShellExecute = false;
p.StartInfo.RedirectStandardOutput = true;
p.StartInfo.FileName = "sqlplus";
p.StartInfo.Arguments = string.Format("xxx/xxx@{0} @{1}", in_database, s);

bool started = p.Start();
// important ... read stream input before waiting for exit.
// this avoids deadlock.
string output = p.StandardOutput.ReadToEnd();

p.WaitForExit();

Console.WriteLine(output);

if (p.ExitCode != 0)
{
    Console.WriteLine( string.Format("*** Failed : {0} - {1}",s,p.ExitCode));
    break;
}

Which now exits correctly.