An exception occurred while iterating over the results of a query for context type 'HP.Database.HpDatabaseContext'. System.ArgumentOutOfRangeException: operation=0 Parameter name: operation at FirebirdSql.Data.Client.Managed.GdsConnection.ProcessOperation(Int32 operation, IXdrReader xdr) at FirebirdSql.Data.Client.Managed.Version10.GdsDatabase.ReadSingleResponse(Int32 operation) at FirebirdSql.Data.Client.Managed.Version11.GdsDatabase.ProcessDeferredPackets() at FirebirdSql.Data.Client.Managed.Version11.GdsDatabase.ReadOperation() at FirebirdSql.Data.Client.Managed.Version10.GdsDatabase.ReadResponse[TResponse]() at FirebirdSql.Data.Client.Managed.Version10.GdsTransaction.BeginTransaction(TransactionParameterBuffer tpb) at FirebirdSql.Data.Client.Managed.Version10.GdsDatabase.BeginTransaction(TransactionParameterBuffer tpb) at FirebirdSql.Data.FirebirdClient.FbTransaction.BeginTransaction() at FirebirdSql.Data.FirebirdClient.FbCommand.Prepare(Boolean returnsSet) at FirebirdSql.Data.FirebirdClient.FbCommand.ExecuteCommand(CommandBehavior behavior, Boolean returnsSet) at FirebirdSql.Data.FirebirdClient.FbCommand.ExecuteReader(CommandBehavior behavior) at System.Data.Common.DbCommand.ExecuteDbDataReaderAsync(CommandBehavior behavior, CancellationToken cancellationToken) --- End of stack trace from previous location where exception was thrown --- at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) at Microsoft.EntityFrameworkCore.Storage.RelationalCommand.<ExecuteReaderAsync>d__17.MoveNext() --- End of stack trace from previous location where exception was thrown --- at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() at Microsoft.EntityFrameworkCore.Storage.RelationalCommand.<ExecuteReaderAsync>d__17.MoveNext() --- End of stack trace from previous location where exception was thrown --- at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() at Microsoft.EntityFrameworkCore.Storage.RelationalCommand.<ExecuteReaderAsync>d__17.MoveNext() --- End of stack trace from previous location where exception was thrown --- at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) at Microsoft.EntityFrameworkCore.Query.Internal.QueryingEnumerable`1.AsyncEnumerator.<InitializeReaderAsync>d__18.MoveNext() --- End of stack trace from previous location where exception was thrown --- at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) at Microsoft.EntityFrameworkCore.Query.Internal.QueryingEnumerable`1.AsyncEnumerator.<MoveNextAsync>d__17.MoveNext() 

Failed executing DbCommand (0ms) [Parameters=[@__printerAddress_0='?' (Size = 33)], CommandType='Text', CommandTimeout='30'] SELECT "t7"."TerminalId", "t7"."ActiveGuiSessionId", "t7"."Discriminator", "t7"."Enabled", "t7"."UiContextId", "t7"."Certificate", "t7"."CurrentMode", "t7"."PendingMode", "t7"."TerminalId0", "t7"."Core_AdminPassword", "t7"."Core_AdminPin", "t7"."Core_AdminUsername", "t7"."Core_DefaultLoginMethodDisplay", "t7"."Core_FaxModule", "t7"."Core_GuestLogin", "t7"."Core_GuestLoginScreen", "t7"."Core_IdleTimeout", "t7"."Core_LoginMethod", "t7"."Core_LoginMethodSimple", "t7"."Core_Model", "t7"."Core_PackageUrl", "t7"."Core_PrinterAddress", "t7"."Core_PrinterId", "t7"."Core_SerialNumber", "t7"."TerminalId1", "t7"."Core_SmtpInfo_Address", "t7"."Core_SmtpInfo_Port", "t7"."Core_SmtpInfo_SenderAddress", "t7"."Id", "t7"."AccountSessionReference", "t7"."AccountSessionSessionId", "t7"."Discriminator0", "t7"."EndTime", "t7"."MachineId", "t7"."ModelSrc", "t7"."SelectedProject", "t7"."StartTime", "t7"."TerminalId2", "t7"."Id0", "t7"."User_Domain", "t7"."User_Email", "t7"."User_FullName", "t7"."User_Id", "t7"."User_UserName", "t7"."Reference", "t7"."SessionId", "t7"."Discriminator1", "t7"."GroupId", "t7"."InitialSessionId", "t7"."IsClosed", "t7"."PriceListSrc", "t7"."TerminalId3", "t7"."TerminalIpAddress", "t7"."Username", "t7"."AvailableBalance", "t7"."UnblockedBalance", "t7"."ExclusiveOwnership", "t7"."Rules", "t8"."Id", "t8"."AccountSessionReference", "t8"."AccountSessionSessionId", "t8"."Commited", "t8"."Discriminator", "t8"."JobId", "t8"."BlockedAmount", "t8"."PaidAmount", "t8"."BlockedCountersData" FROM ( SELECT "t"."TerminalId", "t"."ActiveGuiSessionId", "t"."Discriminator", "t"."Enabled", "t"."UiContextId", "t"."Certificate", "t"."CurrentMode", "t"."PendingMode", "t1"."TerminalId" AS "TerminalId0", "t1"."Core_AdminPassword", "t1"."Core_AdminPin", "t1"."Core_AdminUsername", "t1"."Core_DefaultLoginMethodDisplay", "t1"."Core_FaxModule", "t1"."Core_GuestLogin", "t1"."Core_GuestLoginScreen", "t1"."Core_IdleTimeout", "t1"."Core_LoginMethod", "t1"."Core_LoginMethodSimple", "t1"."Core_Model", "t1"."Core_PackageUrl", "t1"."Core_PrinterAddress", "t1"."Core_PrinterId", "t1"."Core_SerialNumber", "t5"."TerminalId" AS "TerminalId1", "t5"."Core_SmtpInfo_Address", "t5"."Core_SmtpInfo_Port", "t5"."Core_SmtpInfo_SenderAddress", "t2"."Id", "t2"."AccountSessionReference", "t2"."AccountSessionSessionId", "t2"."Discriminator" AS "Discriminator0", "t2"."EndTime", "t2"."MachineId", "t2"."ModelSrc", "t2"."SelectedProject", "t2"."StartTime", "t2"."TerminalId" AS "TerminalId2", "t6"."Id" AS "Id0", "t6"."User_Domain", "t6"."User_Email", "t6"."User_FullName", "t6"."User_Id", "t6"."User_UserName", "t3"."Reference", "t3"."SessionId", "t3"."Discriminator" AS "Discriminator1", "t3"."GroupId", "t3"."InitialSessionId", "t3"."IsClosed", "t3"."PriceListSrc", "t3"."TerminalId" AS "TerminalId3", "t3"."TerminalIpAddress", "t3"."Username", "t3"."AvailableBalance", "t3"."UnblockedBalance", "t3"."ExclusiveOwnership", "t3"."Rules" FROM "Terminals" AS "t" LEFT JOIN ( SELECT "t0"."TerminalId", "t0"."Core_AdminPassword", "t0"."Core_AdminPin", "t0"."Core_AdminUsername", "t0"."Core_DefaultLoginMethodDisplay", "t0"."Core_FaxModule", "t0"."Core_GuestLogin", "t0"."Core_GuestLoginScreen", "t0"."Core_IdleTimeout", "t0"."Core_LoginMethod", "t0"."Core_LoginMethodSimple", "t0"."Core_Model", "t0"."Core_PackageUrl", "t0"."Core_PrinterAddress", "t0"."Core_PrinterId", "t0"."Core_SerialNumber" FROM "Terminals" AS "t0" WHERE "t0"."Core_PrinterId" IS NOT NULL AND ("t0"."Core_LoginMethodSimple" IS NOT NULL AND ("t0"."Core_LoginMethod" IS NOT NULL AND ("t0"."Core_IdleTimeout" IS NOT NULL AND ("t0"."Core_FaxModule" IS NOT NULL AND "t0"."Core_DefaultLoginMethodDisplay" IS NOT NULL)))) ) AS "t1" ON "t"."TerminalId" = "t1"."TerminalId" LEFT JOIN ( SELECT "s"."Id", "s"."AccountSessionReference", "s"."AccountSessionSessionId", "s"."Discriminator", "s"."EndTime", "s"."MachineId", "s"."ModelSrc", "s"."SelectedProject", "s"."StartTime", "s"."TerminalId" FROM "Sessions" AS "s" WHERE "s"."Discriminator" IN (CAST(_UTF8'GuiSession' AS VARCHAR(10) CHARACTER SET UTF8), CAST(_UTF8'HpGuiSession' AS VARCHAR(12) CHARACTER SET UTF8)) ) AS "t2" ON "t"."ActiveGuiSessionId" = "t2"."Id" LEFT JOIN ( SELECT "a"."Reference", "a"."SessionId", "a"."Discriminator", "a"."GroupId", "a"."InitialSessionId", "a"."IsClosed", "a"."PriceListSrc", "a"."TerminalId", "a"."TerminalIpAddress", "a"."Username", "a"."AvailableBalance", "a"."UnblockedBalance", "a"."ExclusiveOwnership", "a"."Rules" FROM "AccountSessions" AS "a" WHERE "a"."Discriminator" IN (CAST(_UTF8'CostCenterAccountSession' AS VARCHAR(24) CHARACTER SET UTF8), CAST(_UTF8'CreditAccountSession' AS VARCHAR(20) CHARACTER SET UTF8), CAST(_UTF8'NoAccountSession' AS VARCHAR(16) CHARACTER SET UTF8), CAST(_UTF8'QuotaAccountSession' AS VARCHAR(19) CHARACTER SET UTF8)) ) AS "t3" ON ("t2"."AccountSessionReference" = "t3"."Reference") AND ("t2"."AccountSessionSessionId" = "t3"."SessionId") LEFT JOIN ( SELECT "t4"."TerminalId", "t4"."Core_SmtpInfo_Address", "t4"."Core_SmtpInfo_Port", "t4"."Core_SmtpInfo_SenderAddress" FROM "Terminals" AS "t4" WHERE "t4"."Core_SmtpInfo_SenderAddress" IS NOT NULL OR ("t4"."Core_SmtpInfo_Port" IS NOT NULL OR "t4"."Core_SmtpInfo_Address" IS NOT NULL) ) AS "t5" ON "t1"."TerminalId" = "t5"."TerminalId" LEFT JOIN ( SELECT "s0"."Id", "s0"."User_Domain", "s0"."User_Email", "s0"."User_FullName", "s0"."User_Id", "s0"."User_UserName" FROM "Sessions" AS "s0" WHERE "s0"."User_Id" IS NOT NULL ) AS "t6" ON "t2"."Id" = "t6"."Id" WHERE ("t"."Discriminator" = CAST(_UTF8'HpTerminal' AS VARCHAR(10) CHARACTER SET UTF8)) AND ("t"."Enabled" AND ("t1"."Core_PrinterAddress" = CAST(@__printerAddress_0 AS VARCHAR(8191)))) ROWS (2) ) AS "t7" LEFT JOIN ( SELECT "a0"."Id", "a0"."AccountSessionReference", "a0"."AccountSessionSessionId", "a0"."Commited", "a0"."Discriminator", "a0"."JobId", "a0"."BlockedAmount", "a0"."PaidAmount", "a0"."BlockedCountersData" FROM "Allocations" AS "a0" WHERE "a0"."Discriminator" IN (CAST(_UTF8'CreditAllocation' AS VARCHAR(16) CHARACTER SET UTF8), CAST(_UTF8'NoAllocation' AS VARCHAR(12) CHARACTER SET UTF8), CAST(_UTF8'QuotaAllocation' AS VARCHAR(15) CHARACTER SET UTF8)) ) AS "t8" ON (("t7"."Reference" = "t8"."AccountSessionReference") OR ("t7"."Reference" IS NULL AND "t8"."AccountSessionReference" IS NULL)) AND (("t7"."SessionId" = "t8"."AccountSessionSessionId") OR ("t7"."SessionId" IS NULL AND "t8"."AccountSessionSessionId" IS NULL)) ORDER BY "t7"."TerminalId", "t8"."Id" 

DatabaseContext .Terminals .Include(t => t.ActiveGuiSession) .ThenInclude(s => s.AccountSession) .ThenInclude(a => a.Allocations) .SingleOrDefaultAsync(t => t.Enabled && t.Core.PrinterAddress == printerAddress);