MySQL - Entity : The value for column 'IsPrimaryKey' in table 'TableDetails' is DBNull

Question

I am using Visual Studio 2013 with Entity Framework 5 and MySQL Server 5.7.9.

When trying to create a Model from the database (or 'Update Model From Database') the following message appears:

'System.Data.StrongTypingException: The value for column 'IsPrimaryKey' in table 'TableDetails' is DBNull . ---> System.InvalidCastException: Specified cast is not valid.

I know that this question has been asked before, but i haven't find any solution. Also i don't have the option of downgrading to MySQL 5.6.

The problem occurs even for a simple table.

The sample table

CREATE TABLE new_table (   id int(11) NOT NULL AUTO_INCREMENT,   name varchar(45) NOT NULL,   PRIMARY KEY (id) )  ENGINE = InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8; 

If the table consists only from the Primary Key then the model is being created as it should.

EDIT: If i make both the fields PRIMARY Keys the model is being created without any errors.

Does anyone have any idea about this?

Kind Regards.

The full error stack:

Unable to generate the model because of the following exception: 'System.Data.StrongTypingException: The value for column 'IsPrimaryKey' in table 'TableDetails' is DBNull. ---> System.InvalidCastException: Specified cast is not valid. at Microsoft.Data.Entity.Design.VersioningFacade.ReverseEngineerDb.SchemaDiscovery.TableDetailsRow.get_IsPrimaryKey() --- End of inner exception stack trace --- at Microsoft.Data.Entity.Design.VersioningFacade.ReverseEngineerDb.SchemaDiscovery.TableDetailsRow.get_IsPrimaryKey() at Microsoft.Data.Entity.Design.VersioningFacade.ReverseEngineerDb.StoreModelBuilder.CreateProperties(IList1 columns, IList1 errors, List1& keyColumns, List1& excludedColumns, List1& invalidKeyTypeColumns) at Microsoft.Data.Entity.Design.VersioningFacade.ReverseEngineerDb.StoreModelBuilder.CreateEntityType(IList1 columns, Boolean& needsDefiningQuery) at Microsoft.Data.Entity.Design.VersioningFacade.ReverseEngineerDb.StoreModelBuilder.CreateEntitySets(IEnumerable1 tableDetailsRows, EntityRegister entityRegister, IList1 entitySetsForReadOnlyEntityTypes, DbObjectType objectType) at Microsoft.Data.Entity.Design.VersioningFacade.ReverseEngineerDb.StoreModelBuilder.CreateEntitySets(IEnumerable1 tableDetailsRowsForTables, IEnumerable1 tableDetailsRowsForViews, EntityRegister entityRegister) at Microsoft.Data.Entity.Design.VersioningFacade.ReverseEngineerDb.StoreModelBuilder.Build(StoreSchemaDetails storeSchemaDetails) at Microsoft.Data.Entity.Design.VisualStudio.ModelWizard.Engine.ModelGenerator.CreateStoreModel() at Microsoft.Data.Entity.Design.VisualStudio.ModelWizard.Engine.ModelGenerator.GenerateModel(List1 errors) at Microsoft.Data.Entity.Design.VisualStudio.ModelWizard.Engine.ModelBuilderEngine.GenerateModels(String storeModelNamespace, List1 errors) at Microsoft.Data.Entity.Design.VisualStudio.ModelWizard.Engine.ModelBuilderEngine.GenerateModel(EdmxHelper edmxHelper)'. Loading metadata from the database took 00:00:00.5856317.

Answer 1

Entity Framework (version 6.1.3) and MySQL Server (>= 5.7.6)

One way to resolve the issue is,

1. Open Services (services.msc) and restart MySQL57 service. 2. Execute the following commands in MySQL.    use <<database name>>;    set global optimizer_switch='derived_merge=OFF'; 3. Update the .edmx. 

It's a late reply. But hope it will help somebody.

Thanks.

Answer 2

This is a know bug: http://bugs.mysql.com/bug.php?id=79163

Run the command on mysql console:

set global optimizer_switch='derived_merge=off'

OR

set @@optimizer_switch='derived_merge=OFF'

(this one worked for me)

Verify that the change is effective with this command:

SELECT @@optimizer_switch\G

https://dev.mysql.com/doc/refman/5.7/en/switchable-optimizations.html