recurring error in logs

Discussion of open issues, suggestions and bugs regarding ADO.NET provider for Oracle
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Posts: 39
Joined: Tue 20 Jul 2010 15:13

recurring error in logs

Post by wgkwvl » Fri 12 Aug 2011 10:58

Hi, we are using devart 6.0.xx with oracle and I notice this error occuring sporadically in my log file.
this is our connection string :

Type : System.Data.EntityException, System.Data.Entity, Version=, Culture=neutral, PublicKeyToken=b77a5c561934e089
Message : The underlying provider failed on Open.
Source : System.Data.Entity
Help link :
Data : System.Collections.ListDictionaryInternal
TargetSite : Void OpenStoreConnectionIf(Boolean, System.Data.Common.DbConnection, System.Data.Common.DbConnection, System.String, System.String, Boolean ByRef)
Stack Trace : at System.Data.EntityClient.EntityConnection.OpenStoreConnectionIf(Boolean openCondition, DbConnection storeConnectionToOpen, DbConnection originalConnection, String exceptionCode, String attemptedOperation, Boolean& closeStoreConnectionOnFailure)
at System.Data.EntityClient.EntityConnection.Open()
at System.Data.Objects.ObjectContext.EnsureConnection()
at System.Data.Objects.ObjectQuery`1.GetResults(Nullable`1 forMergeOption)
at System.Data.Objects.ObjectQuery`1.System.Collections.Generic.IEnumerable.GetEnumerator()
at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection)
at System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source)
at Afda.BL.Afda_PatientenServerSideValidator.DoValidate(Object objectToValidate, Object currentTarget, String key, ValidationResults validationResults)
at Microsoft.Practices.EnterpriseLibrary.Validation.Validators.AndCompositeValidator.DoValidate(Object objectToValidate, Object currentTarget, String key, ValidationResults validationResults)
at Microsoft.Practices.EnterpriseLibrary.Validation.Validators.GenericValidatorWrapper`1.DoValidate(T objectToValidate, Object currentTarget, String key, ValidationResults validationResults)
at Microsoft.Practices.EnterpriseLibrary.Validation.Validator`1.Validate(T target, ValidationResults validationResults)
at Afda.BL.Afda_PatientenBL.Validate(Afda_Patienten item, String afdeling_cd)
at Afda.BL.Afda_PatientenBL.Save(Afda_Patienten item, String afdeling_cd)

atm we have no idea what causes it , or how to reproduce it

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Post by Shalex » Mon 15 Aug 2011 15:56

Please try the following:
1. Check the inner exception (with the Devart call stack). The message of inner exception can help to identify the reason of the problem more clearly.
2. Make sure that there are no any network and Oracle server problems when the error occurs.
3. Upgrade to the latest version (6.30.202) of dotConnect of Oracle.
4. Localize the problem and send us a small test project with your model and corresponding DDL/DML script to reproduce the issue in our environment.

Posts: 3
Joined: Wed 09 May 2012 09:27

Re: recurring error in logs

Post by burnEF » Wed 09 May 2012 10:11


we have a problem with sporadic "hangs" of a Intranet Web Application ( ASP.Net 4.0, dotconnect 6.50.244, oracle client 10g, IIS7, Windows Server 2008).

Exception message: The underlying provider failed on Open
Message: Server did not respond within the specified timeout interval

It seems to be a problem with the LAN (Web-Server <-> Oracle-Server).
The LAN is unfortunately sometimes quite instable.

I read in most of your forum answers regarding such a problem:
"Be sure there are no network problems..."

So now we are in the situation of having spordic network problems.
How does dotconnect/oracle client deal with such problems and what can we do to prevent the application from these "hangs"


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Posts: 2192
Joined: Wed 02 Nov 2011 09:44

Re: recurring error in logs

Post by Pinturiccio » Fri 11 May 2012 11:52

If you have unstable network try using 'ValidateConnection=true;' OracleConnection connection string parameter.
For more information, please refer to ... ction.html

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