This issue was reported via Connect http://connect.microsoft.com/VisualStudio/feedback/details/761883/vs-give-unknown-error-message-while-generating-db-from-ef
The Connect issue records that a few different folks have hit this problem. We haven't been able to reproduce it but it seems like the steps are:
1. Create a model that targets a non-SQL Server database using VS2010
1. Upgrade to VS2012
1. Select 'Generate database from model...'
The result is an error:
```
---------------------------
Microsoft Visual Studio
---------------------------
An exception of type 'Microsoft.VSDesigner.Data.Local.ConnectionStringConverterServiceException' occurred while attempting to generate the database script from the model. The exception message is: ''.
---------------------------
ОК
---------------------------
```
We definitely need to fix the error message (note the empty string at the end of the message). It looks like ConnectionStringConverterServiceException is owned by another team at Microsoft so we will probably need their help.
If we are able to reproduce the issue we also need to understand why the connection string is becoming invalid.
Here are some notes on a workaround provided by Lawrence:
> The error is coming from not being able to interpret the connection string. We don't own the module that does that but from reading the forums it looks like this can often happen if the provider is not properly installed. So if you are upgrading VS make sure you re-install your provider. Once that's done, as an easy workaround, comment out the relevant connection string in your app or web.config. Then go through "Update Model from Database" (selecting nothing new if that's what you want). When it detects that there is no connection string associated with the model it will offer you the page where you get to choose which connection to use. Select your connection and a new connection string with the appropriate format should be put in your .config file.
Comments: __Solution for the above Problem__ I found the solution and i tested and it works fine. Actually two approached are there one can use any approach. ____Approach 1____ In this approach comment or delete the connection string temporarily and select the update from database option it will open the wizard and ask the connection string and guide you through wizard and you will able to update the entity model. __Approach 2__ If your problem is solved from the above approach then it is great but in some cases it throws another error like An Exception has been occurred. The error is "Event Log is full" To overcome from this error follow below steps. 1 Open control panel and go to Administrative Tools 2 Open Event Viewer. 3 Right click the Application and select Properties. 4 Increase the size of log file and make sure that it is in multiple of 64K. 5 Apply the changes and save it. Now go to entity model and try to update it and it works. __Mijal Mistry MCP,MCTS__
The Connect issue records that a few different folks have hit this problem. We haven't been able to reproduce it but it seems like the steps are:
1. Create a model that targets a non-SQL Server database using VS2010
1. Upgrade to VS2012
1. Select 'Generate database from model...'
The result is an error:
```
---------------------------
Microsoft Visual Studio
---------------------------
An exception of type 'Microsoft.VSDesigner.Data.Local.ConnectionStringConverterServiceException' occurred while attempting to generate the database script from the model. The exception message is: ''.
---------------------------
ОК
---------------------------
```
We definitely need to fix the error message (note the empty string at the end of the message). It looks like ConnectionStringConverterServiceException is owned by another team at Microsoft so we will probably need their help.
If we are able to reproduce the issue we also need to understand why the connection string is becoming invalid.
Here are some notes on a workaround provided by Lawrence:
> The error is coming from not being able to interpret the connection string. We don't own the module that does that but from reading the forums it looks like this can often happen if the provider is not properly installed. So if you are upgrading VS make sure you re-install your provider. Once that's done, as an easy workaround, comment out the relevant connection string in your app or web.config. Then go through "Update Model from Database" (selecting nothing new if that's what you want). When it detects that there is no connection string associated with the model it will offer you the page where you get to choose which connection to use. Select your connection and a new connection string with the appropriate format should be put in your .config file.
Comments: __Solution for the above Problem__ I found the solution and i tested and it works fine. Actually two approached are there one can use any approach. ____Approach 1____ In this approach comment or delete the connection string temporarily and select the update from database option it will open the wizard and ask the connection string and guide you through wizard and you will able to update the entity model. __Approach 2__ If your problem is solved from the above approach then it is great but in some cases it throws another error like An Exception has been occurred. The error is "Event Log is full" To overcome from this error follow below steps. 1 Open control panel and go to Administrative Tools 2 Open Event Viewer. 3 Right click the Application and select Properties. 4 Increase the size of log file and make sure that it is in multiple of 64K. 5 Apply the changes and save it. Now go to entity model and try to update it and it works. __Mijal Mistry MCP,MCTS__
