c# – Npgsql / EF 6 – json列

我正在尝试使用 JSON列创建迁移.这是我试过的：

[Column(TypeName = "Jsonb")]
    public string Data { get; set; }

    [Column(TypeName = "Json")]
    public string Data { get; set; }

    modelBuilder.Entity<Member>().Property(p => p.Data).HasColumnType("Json");

    modelBuilder.Entity<Member>().Property(p => p.Data).HasColumnType("Jsonb");

什么都没有,这是例外：

system.invalidOperationException: Sequence contains no matching element
at System.Linq.Enumerable.Single[TSource](IEnumerable1 source,Func2 predicate)
at System.Data.Entity.Utilities.DbProviderManifestExtensions.GetStoreTypeFromName(DbProviderManifest providerManifest,String name)
at System.Data.Entity.ModelConfiguration.Configuration.Properties.Primitive.PrimitivePropertyConfiguration.ConfigureColumn(EdmProperty column,EntityType table,DbProviderManifest providerManifest)
at System.Data.Entity.ModelConfiguration.Configuration.Properties.Primitive.PrimitivePropertyConfiguration.Configure(EdmProperty column,DbProviderManifest providerManifest,Boolean allowOverride,Boolean fillFromExistingConfiguration)
at System.Data.Entity.ModelConfiguration.Configuration.Properties.Primitive.PrimitivePropertyConfiguration.<>c__displayClass4.b__3(Tuple2 pm)
at System.Data.Entity.Utilities.IEnumerableExtensions.Each[T](IEnumerable1 ts,Action1 action)
at System.Data.Entity.ModelConfiguration.Configuration.Properties.Primitive.PrimitivePropertyConfiguration.Configure(IEnumerable1 propertyMappings,Boolean fillFromExistingConfiguration)
at System.Data.Entity.ModelConfiguration.Configuration.Types.StructuralTypeConfiguration.ConfigurePropertyMappings(IList1 propertyMappings,Boolean allowOverride)
at System.Data.Entity.ModelConfiguration.Configuration.Types.EntityTypeConfiguration.ConfigurePropertyMappings(DbDatabaseMapping databaseMapping,EntityType entityType,Boolean allowOverride)
at System.Data.Entity.ModelConfiguration.Configuration.Types.EntityTypeConfiguration.Configure(EntityType entityType,DbDatabaseMapping databaseMapping,DbProviderManifest providerManifest)
at System.Data.Entity.ModelConfiguration.Configuration.ModelConfiguration.ConfigureEntityTypes(DbDatabaseMapping databaseMapping,ICollection1 entitySets,DbProviderManifest providerManifest)
at System.Data.Entity.ModelConfiguration.Configuration.ModelConfiguration.Configure(DbDatabaseMapping databaseMapping,DbProviderManifest providerManifest)
at System.Data.Entity.DbModelBuilder.Build(DbProviderManifest providerManifest,DbProviderInfo providerInfo)
at System.Data.Entity.DbModelBuilder.Build(DbConnection providerConnection)
at System.Data.Entity.Internal.LazyInternalContext.CreateModel(LazyInternalContext internalContext)
at System.Data.Entity.Internal.RetryLazy2.GetValue(TInput input)
at System.Data.Entity.Internal.LazyInternalContext.InitializeContext()
at System.Data.Entity.Internal.InternalContext.GetEntitySetAndBaseTypeForType(Type entityType)
at System.Data.Entity.Internal.Linq.InternalSet1.Initialize()
at System.Data.Entity.Internal.Linq.InternalSet1.get_InternalContext()
at System.Data.Entity.Internal.Linq.InternalSet1.get_Local()
at System.Data.Entity.DbSet`1.get_Local()
at System.Data.Entity.DbModelBuilderExtensions.RegisterUserAccountChildTablesForDelete[TKey,TAccount,TUserClaim,TLinkedAccount,TLinkedAccountClaim,TPasswordResetSecret,TTwoFactorAuthToken,TUserCertificate](DbContext ctx) in c:\ballen\github\brockallen\brockAllen.MembershipReboot\src\brockAllen.MembershipReboot.Ef\DbModelBuilderExtensions.cs:line 26

这是我的配置：

<package id="EntityFramework" version="6.1.1" targetFramework="net452" />
<package id="EntityFramework6.Npgsql" version="3.1.1" targetFramework="net452" />
<package id="Npgsql" version="3.1.6" targetFramework="net452" />

解决方法

因此,这是完全可行的,但需要修改生成的迁移,而不是注释模型或使用流畅的配置.在生成的迁移中,更改数据列的声明以使用storeType和defaultValuesql参数：

data = c.String(nullable: false,storeType: "jsonb",defaultValuesql: "'{}'::jsonb")

我可以确认这适用于Npgsql 3.1.7与EntityFramework6.Npgsql 3.1.1,并将保存和加载适用的实体没有问题.无法担保早期版本.