Devart Forums

Andrew

Hello

I have a couple general usage questions about the context file.

Which of the following do I use in my web application design?

--1 Context per page request

--1 Context per session

--multiple contexts per page request

--1 static context for server

Also, is it required for me to call the Dispose() method of the context when I am through with it, or are the database connections handled in some other fashion?

Thank You,
Andrew

Andrew

Hello.

I have noticed that adding an OrderByDescending to the end of a linq query adds about 90ms of time. Is this just the overhead of linq? Or is there something wrong? The equivalent query in sql runs much quicker.

Thanks
Andrew

Andrew

Solved

Apparently my project doesn't copy the devart dll's into the bin folder when i compile. I manually copied them in and the problem when away

Thanks
Andrew

Andrew

Hi all,

When I try to upgrade to the new version of devart, everything compiles and runs fine until I try to login to my application, which is using Form authentication.

Code: Select all

Server Error in '/' Application.
Cannot convert parameter value of type 'System.String' to MySQL type 'MySqlType.TimeStamp'.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.InvalidCastException: Cannot convert parameter value of type 'System.String' to MySQL type 'MySqlType.TimeStamp'.

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:

[InvalidCastException: Cannot convert parameter value of type 'System.String' to MySQL type 'MySqlType.TimeStamp'.]
   Devart.Data.MySql.MySqlParameter.a() +217
   Devart.Data.MySql.ax.a(Int32& A_0, ArrayList& A_1) +2517
   Devart.Data.MySql.a1.e() +209
   Devart.Data.MySql.a1.o() +31
   Devart.Data.MySql.MySqlCommand.a(CommandBehavior A_0, IDisposable A_1, Int32 A_2, Int32 A_3) +873
   Devart.Common.DbCommandBase.ExecuteDbDataReader(CommandBehavior behavior) +193
   System.Data.Common.DbCommand.ExecuteReader() +9
   Devart.Common.DbCommandBase.ExecuteNonQuery() +53
   Devart.Common.Web.Providers.DbMembershipProvider.a(String A_0, Object[] A_1) +761

[ProviderException: An exception occurred. Please contact your administrator.]
   Devart.Common.Web.Providers.DbMembershipProvider.a(String A_0, Object[] A_1) +824
   Devart.Common.Web.Providers.DbMembershipProvider.ValidateUser(String username, String password) +260
   System.Web.UI.WebControls.Login.OnAuthenticate(AuthenticateEventArgs e) +160
   System.Web.UI.WebControls.Login.AttemptLogin() +105
   System.Web.UI.WebControls.Login.OnBubbleEvent(Object source, EventArgs e) +99
   System.Web.UI.Control.RaiseBubbleEvent(Object source, EventArgs args) +35
   System.Web.UI.WebControls.Button.OnCommand(CommandEventArgs e) +115
   System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) +163
   System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +7
   System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +11
   System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +33
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1746

Help!
Thanks
Andrew[/code]

Andrew

Hello

I just upgraded to 5.00.2 and ran into a problem.

Code: Select all

Server Error in '/' Application.
Cannot convert parameter value of type 'System.Int32' to MySQL type 'MySqlType.Time'.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.InvalidCastException: Cannot convert parameter value of type 'System.Int32' to MySQL type 'MySqlType.Time'.

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:

[InvalidCastException: Cannot convert parameter value of type 'System.Int32' to MySQL type 'MySqlType.Time'.]
   Devart.Common.Web.Providers.DbSessionStateStore.CreateUninitializedItem(HttpContext context, String id, Int32 timeout) +1097
   System.Web.SessionState.SessionStateModule.CreateUninitializedSessionState() +44
   System.Web.SessionState.SessionStateModule.BeginAcquireState(Object source, EventArgs e, AsyncCallback cb, Object extraData) +594
   System.Web.AsyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +90
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +161

Apparently my session is no longer working. I get this error no matter what page I am on. Any advice would be appreciated.
Thanks
Andrew

Andrew

Hello

I was wondering if support for nullable fields will be added.

For example, I have a field in the MySQL database of Decimal type. This type can be null. The shema modeller reflects this but the code generated does not.

I noticed a new version of Linq has been provided but have not been able to upgrade yet. So sorry if this fix has already been implemented.

Thanks
AFrieze

Andrew

Shalex
Sorry about forgetting the client table. Here it is.

Code: Select all


DROP TABLE IF EXISTS `findlocation`.`client`;
CREATE TABLE  `findlocation`.`client` (
  `client_id` int(10) unsigned NOT NULL auto_increment,
  `client_name` varchar(45) NOT NULL,
  `xionetic_id` int(10) unsigned NOT NULL,
  PRIMARY KEY  (`client_id`)
) ENGINE=InnoDB AUTO_INCREMENT=956 DEFAULT CHARSET=latin1;

The project no longer has this error as I have programmed around it with a one column primary key. I can try to replicate it again if it would be helpful to you.

Thanks!
Andrew

Andrew

Hello.

I have a problem that I believe stems from the use of two columns as the primary key. Whenever I try to query the table with linq; i get this error:

Code: Select all

[InvalidOperationException: Sequence contains no matching element]
   System.Linq.Enumerable.Single(IEnumerable`1 source, Func`2 predicate) +320
   Devart.Data.Linq.MultiKeyManager`2.a() +309
   Devart.Data.Linq.MultiKeyManager`2.a(Type A_0) +491
   Devart.Data.Linq.MultiKeyManager`2.a(Type A_0) +230
   Devart.Data.Linq.MultiKeyManager`2.CreateDefault() +264
   Devart.Data.Linq.MultiKeyManager`2.a(T A_0) +125
   Devart.Data.Linq.Provider.EntityReader`2.a() +70
   Devart.Data.Linq.Provider.ObjectReader`1.MoveNext() +22
   FindLocationLib.XioneticClasses.DBUtil.GetXioneticUserByUserId(String userId) in C:\Develop\FindLocationDevelop\FindLocationLib\XioneticClasses\DBUtil.cs:24
   FindLocation.Login.Login1_LoggedIn(Object sender, EventArgs e) in C:\Develop\FindLocationDevelop\FindLocation\Login.aspx.cs:34
   System.Web.UI.WebControls.Login.OnLoggedIn(EventArgs e) +105
   System.Web.UI.WebControls.Login.AttemptLogin() +205
   System.Web.UI.WebControls.Login.OnBubbleEvent(Object source, EventArgs e) +99
   System.Web.UI.Control.RaiseBubbleEvent(Object source, EventArgs args) +35
   System.Web.UI.WebControls.Button.OnCommand(CommandEventArgs e) +115
   System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) +163
   System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +7
   System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +11
   System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +33
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1746

And here is the SQL Create statement for my table:

Code: Select all

DROP TABLE IF EXISTS `findlocation`.`fluser`;
CREATE TABLE  `findlocation`.`fluser` (
  `user_id` varchar(45) NOT NULL,
  `client_id` int(10) unsigned NOT NULL,
  `parent_id` varchar(45) default NULL,
  PRIMARY KEY  (`user_id`,`client_id`),
  KEY `FK_fluser_1` (`client_id`),
  CONSTRAINT `FK_fluser_1` FOREIGN KEY (`client_id`) REFERENCES `client` (`client_id`) ON DELETE CASCADE ON UPDATE CASCADE
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

Any ideas?

Thanks!
AFrieze

P.s. Really enjoying linq!

Andrew

Hi all

I am experimenting with Linq and the Schema Modeller. I have a database id field that is an AutoIncrement field.

I can successfully insert a new row with linq, but the object is not updated with the id.

Example:

Code: Select all

client c = new client { client_name = clRow["name"].ToString() };

//client has an auto increment field called client_id

db.clients.InsertOnSubmit(c);
db.SubmitChanges();

Console.Write("client_id = " + c.client_id); //client_id is 0

In the Schema Modeller these attributes are set:

Access: Public
Delay Loaded: False
Inheritance Modifier: None
Name: client_id
Type: System.Int64

Auto Generated Value: True
Auto-Sync: OnInsert
Is Version: False
Nullable: False
Primary Key: True
Read Only: False
Server Data Type: int(10) Not Null Auto_increment
Source: client_id
Update Check: Always

Any ideas on why the id field is not synced on my object after the submit?
Thanks!
Andrew

[/code]

Devart Forums

Search found 9 matches

Context File

Linq OrderByDescending slow

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Linq with Null values

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