How to view LINQ Generated SQL statements?

linq

You can always attach something to the .Log property of your DataContext. That will show all the SQL commands as they are sent.

I do this in my base for data access objects and output it to the Visual Studio debug console. As the objects create their DataContext I check it see if its debug and attach a TextWritter helper class like this:

dbDataContext _dB = new dbDataContext();
_dB.CommandTimeout = 5000;

#if DEBUG
    _dB.Log = new DebugTextWriter();
#endif

Here is the helper object for output to the debug console:

//utility class for output of TextWriter for the Visual Sudio Debug window
class DebugTextWriter : System.IO.TextWriter
{
    public override void Write(char[] buffer, int index, int count)
    {
        System.Diagnostics.Debug.Write(new String(buffer, index, count));
    }

    public override void Write(string value)
    {
        System.Diagnostics.Debug.Write(value);
    }

    public override Encoding Encoding
    {
        get { return System.Text.Encoding.Default; }
    }
}

Here is what I found using ObjectQuery Method. Using console for testing, you can do the following:

Create an Extension Method as below, then call it. Say Product product, then SQL prints out as product.ToTraceString.

public static class MyExtensions
{
    public static string ToTraceString<T>(this IQueryable<T> t)
    {
        string sql = "";
        ObjectQuery<T> oqt = t as ObjectQuery<T>;
        if (oqt != null)
            sql = oqt.ToTraceString();
        return sql;
    }
}

You could have a look at the Linq-to-SQL Debug Visualizer, or just hover your mouse over your Linq-to-SQL query (tooltip should show generated SQL), or access:

context.GetCommand(query).CommandText

 var q = from img in context.Images
                    ...
         select img;
 string sql = q.ToString();

sql will contain the sql select query.

EDIT: disadvantage: parameters won't have any values at this time

How to view LINQ Generated SQL statements?

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