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Retrieve LINQ to sql statement (IQueryable) WITH parameters

开发者 https://www.devze.com 2023-03-12 15:01 出处:网络
I\'m trying to figure out if there\'s a way to retrieve the (full) sql statement that gets executed on the database server.

I'm trying to figure out if there's a way to retrieve the (full) sql statement that gets executed on the database server.

I found something already, but it does not exactly what I would like:

IQueryable<SomeType> someQuery = ...
string command = dataContext.GetCommand(query).CommandText;

In 开发者_如何学JAVAmy case this gives me a command string something like:

SELECT TOP (50) [t0].[ID], ....
FROM [dbo].[someTable] AS [t0]
WHERE ([t0].[someColumn] IS NOT NULL) AND (([t0].[someColumn]) IN (@p0))

On database there's executed:

exec sp_executesql N'SELECT TOP (50) [t0].[ID], ...
FROM [dbo].[someTable] AS [t0]
WHERE ([t0].[someColumn] IS NOT NULL) AND (([t0].[someColumn]) IN (@p0, @p1))',N'@p0  int,@p1 int',@p0=401,@p1=201

Is there a way to retrieve this 'full' statement (so also the parameter values) from C# code?


You can also see the generated sql query if you have an instance of IQueryable<T> and call the .ToString() method.
For Example:

var db = new DbContext();
IQueryable<Blog> query = db.Blog.Where(tt=> tt.Id > 100).OrderByDescending(tt=>tt.Id);
var sqlString = query.ToString();
Console.WriteLine(sqlString);

This will generate an output of:

SELECT [Extent1].[Id] AS [Id], 
[Extent1].[Title] AS [Title], 
[Extent1].[Author] AS [Author], 
[Extent1].[Text] AS [Text], 
[Extent1].[CreatedAt] AS [CreatedAt], 
[Extent1].[UpdatedAt] AS [UpdatedAt]
FROM [dbo].[Blogs] AS [Extent1]
WHERE [Extent1].[Id] > 100
ORDER BY [Extent1].[Id] DESC


Once you get the Command you can print the CommandText and then loop through the Parameters collection and print all the individual parameters.

Also there is the linq-to-sql debug visualizer which does the same in debug mode.

A really nice tool to view the queries as they are happening is the Linq-to-sql profiler


In the latest version of EF Core 5 ToQueryString,

query.ToQueryString()


(SqlCommand)dataContext.GetCommand(query)

will give you access to Parameters collection.


I'm using Datacontext.Log property to get the generated SQL Statement (it includes the statement text, and parameters).

Just set YourDataContext.Log = SomeTextWriter.

It can be written to a file (Log = new StreamWriter(@"c:\temp\linq.log")) or to debug window, see this post


When viewing the IQueryable in the Locals pane, you can access DebugView > Query, which will contain the SQL statement.

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