I am trying to view SQL generated by Linq to SQL in the SQL Server Profiler (2005).
I can see the sql sent to the server from anything except for linq to sql.
I'm betting that I need to change event selections for the trace, but not sure what else to select.
I am currently only selecting this:
SQL:StmtCompleted - TextData & SPID
I don't want to use data context logging nor the SQL Debug Visualizer. I need to use the profiler.
Why can I not see the LINQ to SQL queries?
Thanks.
EDIT
I added SQL:BatchCompleted and that hasn't helped.
EDIT 2
I added the event RPC:Completed which is found under the Stored Procedures category in event selection. This worked!
You need RPC call - the queries are executed as exec_sql.
Are you including enough of the options in the SQL Profiler to see the BatchCompleted events, too?
Marc
There is also an option in the data context class to enable log in the client side. When log is enabled is possible to see the queries.
See this link:
http://www.davidhayden.com/blog/dave/archive/2007/08/17/DataContextLogLoggingLINQToSQLOutputConsoleDebuggerOuputWindow.aspx
Had the same problem and none of the solutions above worked for me.
What worked for me was adding ToList() enumerator to the query.
Before:
var data = null == id ?
(from ...
select new
{
...
})
:
(from ..
select new
{
...
});
After:
var data = null == id ?
(from ...
select new
{
...
}).ToList()
:
(from ..
select new
{
...
}).ToList();
foreach (var obj in data)
{
xxx = obj.somename; --> now you can see the sql query in Profiler
Related
I have a parameterised named Query like this :
Query moveOutQuery = session.createSQLQuery(moveOutQueryStr.toString())
.addEntity(MyClass.class)
.setParameter("assignmentStatus", Constants.CHECKED_OUT)
I want to see the actual SQL query with parameters filled in. However while debugging I only get the following query:
Select * from my_assignment WHERE assignment_status in ( :assignmentStatus )
Why isn't the assignmentStatus being substituted for its real value?
Why isn't the assignmentStatus being substituted for its real value?
This is because NHibernate use query parameters to input values. This is efficient in many cases and also helpful against SQL Injection attack. Parameters are sent separately. You can find them at the bottom if SQL is logged as explained below.
You may log each SQL to file as explained below.
This is implemented through log4net.dll; you need to add reference.
Add namespaces as below:
using log4net;
using log4net.Appender;
using log4net.Core;
using log4net.Layout;
using log4net.Repository.Hierarchy;
Configure log4net in NHibernate as below:
Hierarchy hierarchy = (Hierarchy)LogManager.GetRepository();
hierarchy.Root.RemoveAllAppenders();
FileAppender fileAppender = new FileAppender();
fileAppender.Name = "NHFileAppender";
fileAppender.File = logFilePath;
fileAppender.AppendToFile = true;
fileAppender.LockingModel = new FileAppender.MinimalLock();
fileAppender.Layout = new PatternLayout("%d{yyyy-MM-dd HH:mm:ss}:%m%n%n");
fileAppender.ActivateOptions();
Logger logger = hierarchy.GetLogger("NHibernate.SQL") as Logger;
logger.Additivity = false;
logger.Level = Level.Debug;
logger.AddAppender(fileAppender);
hierarchy.Configured = true;
You also need to set ShowSql while configuration as below:
configuration.SetProperty(NHibernate.Cfg.Environment.ShowSql, "true");
configuration.SetProperty(NHibernate.Cfg.Environment.FormatSql, "true");
You need to call this code once at startup of your application. Output log includes values of parameters as well.
Following is the code:
session.CreateSQLQuery("SELECT * FROM MyEntity WHERE MyProperty = :MyProperty")
.AddEntity(typeof(MyEntity))
.SetParameter("MyProperty", "filterValue")
.UniqueResult<MyEntity>();
Following is the logged query:
2020-01-09 14:25:39:
SELECT
*
FROM
MyEntity
WHERE
MyProperty = #p0;
#p0 = 'filterValue' [Type: String (4000:0:0)]
As you can see, parameter value filterValue is listed at the bottom.
This works for all query APIs like IQueryOver, IQuery, ISQLQuery etc.
This logs both success and failed statements. You can play with FileAppender and Logger class to meet your additional requirements.
Also refer PatternLayout from documentation. More details can also be found here, here and here. This Q/A discusses the same.
Following Q/A may also help:
Get executed SQL from nHibernate
Using log4net to write to different loggers
How to log SQL calls with NHibernate to the console of Visual Studio?
As you see, this logs the parameter values at bottom of the query. If you want those logged embedded in the query, please refer to this article.
Given the code:
var q = db.TranslationProjectKeys.Where(c => c.ProjectID == forProject.ID);
foreach (var key in q)
{
key.Live = false;
}
db.SubmitChanges();
If I run the SQL server profiler it shows dozens of UPDATE.... SQL statements. I believe this would be considerably faster if this query was executed with one UPDATE statement:
UPDATE TranslationProjectKeys SET Live = 0 WHERE ProjectID = x
Is there a way to make the query execute in this way?
I'm wary of using db.ExecuteCommand("...") as I am aware the context can be cached which can cause some bugs.
You can use EntityFramework.Extended . You can execute multiple update.
For Example
var q = db.TranslationProjectKeys.Where(c => c.ProjectID == forProject.ID).Update(c => new TranslationProjectKey{ Live = false })
linq to sql does not have a built in mass update function (unless something has changed). you could just execute the command manually like
dataContext.ExecuteCommand("UPDATE TranslationProjectKeys SET Live = 0 WHERE ProjectID = {0}", x);
or if you wanted to get fancy, you could try implementing your own mass update functionality like this article shows, but it is MUCH more in depth and complicated (Though it IS possible to do)
Is there any way to display only SQL queries on console when debugging mode is on?
I want to reduce the amount of informations which is displayed.
Thanks for the help ;)
Set environment variables to configure the debug module:
DEBUG=knex:query for just queries
DEBUG=knex:tx for transactions
and DEBUG=knex* for everything.
If what you need is to show the query string, one way is to register a function that logs the query data using the event 'query' that Knex emit just before executing the query.
For example:
var knex = require( 'knex' );
knex.on( 'query', function( queryData ) {
console.log( queryData );
});
After that, before every query, the anonymous function is called and queryData contains json with the information about the query.
Actually, if you're using MySQL, you can set
debug: ['ComQueryPacket']
as part of the config settings for mysql (not Knex).
I'll looking into adding this as an option in Knex though.
I am querying a MS SQL database using Linq and Entity Framework Code First. The requirement is to be able to run a WHERE SomeColumn LIKE '%sometext'clause against the table.
This, on the surface, is a simple requirement that could be accomplished using a simple Linq query like this:
var results = new List<MyTable>();
using(var context = new MyContext())
{
results = context.MyTableQueryable
.Where(x => x.SomeColumn.EndsWith("sometext"))
.ToList();
}
// use results
However, this was not effective in practice. The problem seems to be that the column SomeColumn is not varchar, rather it's a char(31). This means that if a string is saved in the column that is less than 31 characters then there will be spaces added on the end of the string to ensure a length of 31 characters, and that fouls up the .EndsWith() query.
I used SQL Profiler to lookup the exact sql that was generated from the .EndsWith() method. Here is what I found:
--previous query code removed for brevity
WHERE [Extent1].[SomeColumn] LIKE N'%sometext'
So that is interesting. I'm not sure what the N means before '%sometext'. (I'll Google it later.) But I do know that if I take the same query and run it in SSMS without the N like this:
--previous query code removed for brevity
WHERE [Extent1].[SomeColumn] LIKE '%sometext'
Then the query works fine. Is there a way to get Linq and Entity Framework to drop that N from the query?
Please try this...
.Where(x => x.SomeColumn.Trim().EndsWith("sometext"))
Just spoke to my colleague who had a similar issue, see if the following works for you:
[Column(TypeName = "varchar")]
public string SomeColumn
{
get;
set;
}
Apparently setting the type on the column mapping will force the query to recognise it as a VARCHAR, where a string is normally interpreted as an NVARCHAR.
Setting the DBIC_TRACE environment variable to true:
BEGIN { $ENV{DBIC_TRACE} = 1 }
generates very helpful output, especially showing the SQL query that is being executed, but the SQL query is all on one line.
Is there a way to push it through some kinda "sql tidy" routine to format it better, perhaps breaking it up over multiple lines? Failing that, could anyone give me a nudge into where in the code I'd need to hack to add such a hook? And what the best tool is to accept a badly formatted SQL query and push out a nicely formatted one?
"nice formatting" in this context simply means better than "all on one line". I'm not particularly fussed about specific styles of formatting queries
Thanks!
As of DBIx::Class 0.08124 it's built in.
Just set $ENV{DBIC_TRACE_PROFILE} to console or console_monochrome.
From the documentation of DBIx::Class::Storage
If DBIC_TRACE is set then trace information is produced (as when the
debug method is set). ...
debug Causes trace information to be emitted on the debugobj
object. (or STDERR if debugobj has not specifically been set).
debugobj Sets or retrieves the object used for metric collection.
Defaults to an instance of DBIx::Class::Storage::Statistics that is
compatible with the original method of using a coderef as a callback.
See the aforementioned Statistics class for more information.
In other words, you should set debugobj in that class to an object that subclasses DBIx::Class::Storage::Statistics. In your subclass, you can reformat the query the way you want it to be.
First, thanks for the pointers! Partial answer follows ....
What I've got so far ... first some scaffolding:
# Connect to our db through DBIx::Class
my $schema = My::Schema->connect('dbi:SQLite:/home/me/accounts.db');
# See also BEGIN { $ENV{DBIC_TRACE} = 1 }
$schema->storage->debug(1);
# Create an instance of our subclassed (see below)
# DBIx::Class::Storage::Statistics class
my $stats = My::DBIx::Class::Storage::Statistics->new();
# Set the debugobj object on our schema's storage
$schema->storage->debugobj($stats);
And the definition of My::DBIx::Class::Storage::Statistics being:
package My::DBIx::Class::Storage::Statistics;
use base qw<DBIx::Class::Storage::Statistics>;
use Data::Dumper qw<Dumper>;
use SQL::Statement;
use SQL::Parser;
sub query_start {
my ($self, $sql_query, #params) = #_;
print "The original sql query is\n$sql_query\n\n";
my $parser = SQL::Parser->new();
my $stmt = SQL::Statement->new($sql_query, $parser);
#printf "%s\n", $stmt->command;
print "The parameters for this query are:";
print Dumper \#params;
}
Which solves the problem about how to hook in to get the SQL query for me to "pretty-ify".
Then I run a query:
my $rs = $schema->resultset('SomeTable')->search(
{
'email' => $email,
'others.some_col' => 1,
},
{ join => 'others' }
);
$rs->count;
However SQL::Parser barfs on the SQL generated by DBIx::Class:
The original sql query is
SELECT COUNT( * ) FROM some_table me LEFT JOIN others other_table ON ( others.some_col_id = me.id ) WHERE ( others.some_col_id = ? AND email = ? )
SQL ERROR: Bad table or column name '(others' has chars not alphanumeric or underscore!
SQL ERROR: No equijoin condition in WHERE or ON clause
So ... is there a better parser than SQL::Parser for the job?