从流读取时出现异常

Question

运行

Add-Migration

命令时出现以下错误：

Npgsql.NpgsqlException (0x80004005): Exception while reading from stream
 ---> System.TimeoutException: Timeout during reading attempt
   at Npgsql.Internal.NpgsqlReadBuffer.<Ensure>g__EnsureLong|54_0(NpgsqlReadBuffer buffer, Int32 count, Boolean async, Boolean readingNotifications)
   at System.Runtime.CompilerServices.PoolingAsyncValueTaskMethodBuilder`1.StateMachineBox`1.System.Threading.Tasks.Sources.IValueTaskSource.GetResult(Int16 token)
   at Npgsql.Internal.NpgsqlConnector.ReadMessageLong(Boolean async, DataRowLoadingMode dataRowLoadingMode, Boolean readingNotifications, Boolean isReadingPrependedMessage)
   at System.Runtime.CompilerServices.PoolingAsyncValueTaskMethodBuilder`1.StateMachineBox`1.System.Threading.Tasks.Sources.IValueTaskSource<TResult>.GetResult(Int16 token)
   at Npgsql.NpgsqlDataReader.NextResult(Boolean async, Boolean isConsuming, CancellationToken cancellationToken)
   at Npgsql.NpgsqlDataReader.NextResult(Boolean async, Boolean isConsuming, CancellationToken cancellationToken)
   at Npgsql.NpgsqlDataReader.NextResult()
   at Npgsql.NpgsqlCommand.ExecuteReader(Boolean async, CommandBehavior behavior, CancellationToken cancellationToken)
   at Npgsql.NpgsqlCommand.ExecuteReader(Boolean async, CommandBehavior behavior, CancellationToken cancellationToken)
   at Npgsql.NpgsqlCommand.ExecuteScalar(Boolean async, CancellationToken cancellationToken)
   at Npgsql.NpgsqlCommand.ExecuteScalar()
   at Microsoft.EntityFrameworkCore.Storage.RelationalCommand.ExecuteScalar(RelationalCommandParameterObject parameterObject)
   at Microsoft.EntityFrameworkCore.Migrations.HistoryRepository.Exists()
   at Microsoft.EntityFrameworkCore.Migrations.Internal.Migrator.Migrate(String targetMigration)
   at Npgsql.EntityFrameworkCore.PostgreSQL.Migrations.Internal.NpgsqlMigrator.Migrate(String targetMigration)
   at Microsoft.EntityFrameworkCore.Design.Internal.MigrationsOperations.UpdateDatabase(String targetMigration, String connectionString, String contextType)
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.UpdateDatabaseImpl(String targetMigration, String connectionString, String contextType)
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.UpdateDatabase.<>c__DisplayClass0_0.<.ctor>b__0()
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.OperationBase.Execute(Action action)

这就是我的数据库上下文类的样子：

public sealed class ArchivesDbContext(DbContextOptions<ArchivesDbContext> options) 
    : DbContext(options), IUnitOfWork
{
    internal DbSet<Subject> Subjects { get; set; }

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        modelBuilder.HasDefaultSchema(Schemas.Archives);

        modelBuilder.ApplyConfiguration(new SubjectConfiguration());
    }
}

我尝试添加

Keepalive = 1

和

CommandTimeOut = 60

但仍然遇到同样的错误。

我正在使用

Postgres SQL

 中的 

Supabase

Answer 1

我发现命令超时中有拼写错误。 你的拼写：

CommandTimeOut=60

正确拼写：

CommandTimeout=60

除此之外，我在您的代码中没有看到任何问题。也许有一些外部因素导致超时错误。我现在能想到的问题有以下几点：

1。网络连接不良。

解决方案：尝试增加命令超时。可能是120或更多。

2。

Supabase

服务器繁忙。

解决方案：尝试迁移本地系统中的数据库并检查 如果有效的话。