DataConnectionTransaction?StartLoadTransaction(Query query)
{
if (!query.IsAnyPreambles())
{
return(null);
}
DataConnection?dc = null;
if (DataContext is DataConnection dataConnection)
{
dc = dataConnection;
}
else if (DataContext is DataContext dataContext)
{
dc = dataContext.GetDataConnection();
}
if (dc == null || dc.TransactionAsync != null)
{
return(null);
}
return(dc.BeginTransaction(dc.DataProvider.SqlProviderFlags.DefaultMultiQueryIsolationLevel));
}
Task <DataConnectionTransaction?> StartLoadTransactionAsync(Query query, CancellationToken cancellationToken)
{
if (!query.IsAnyPreambles())
{
return(TaskCache.CompletedTransaction);
}
DataConnection?dc = null;
if (DataContext is DataConnection dataConnection)
{
dc = dataConnection;
}
else if (DataContext is DataContext dataContext)
{
dc = dataContext.GetDataConnection();
}
if (dc == null || dc.TransactionAsync != null)
{
return(TaskCache.CompletedTransaction);
}
return(dc.BeginTransactionAsync(dc.DataProvider.SqlProviderFlags.DefaultMultiQueryIsolationLevel, cancellationToken) !);
}
// internal API
internal static bool TryGetDataConnection <T>(this ITable <T> table, [NotNullWhen(true)] out DataConnection?dataConnection)
where T : notnull
{
if (table.DataContext is DataConnection dc)
{
dataConnection = dc;
}
else if (table.DataContext is DataContext dataContext)
{
dataConnection = dataContext.GetDataConnection();
}
else
{
dataConnection = null;
}
return(dataConnection != null);
}
protected override DataConnection CreateDataConnection(LinqToDBConnectionOptions options)
{
return(DataConnection = base.CreateDataConnection(options));
}
private DataConnection?GetConnection(string provider, string?providerLocation, string connectionString, string?additionalConnectionString, out DataConnection?secondaryConnection)
{
secondaryConnection = null;
var returnSecondary = false;
// general rules:
// - specify specific provider used by tool if linq2db supports multiple providers for database
// - if multiple dialects (versions) of db supported - make sure version detection enabled
// other considerations:
// - generate error for databases with windows-only support (e.g. access, sqlce)
// - allow user to specify provider discovery hints (e.g. provider path) for unmanaged providers
switch (provider)
{
case ProviderName.SQLite:
provider = ProviderName.SQLiteClassic;
break;
case ProviderName.SqlServer:
SqlServerTools.AutoDetectProvider = true;
SqlServerTools.Provider = SqlServerProvider.MicrosoftDataSqlClient;
break;
case ProviderName.Firebird:
// TODO: don't forget to add versioning here after Firebird versioning feature merged
break;
case ProviderName.MySql:
// TODO: remove provider hint after MySQL.Data support removed
provider = ProviderName.MySqlConnector;
break;
case ProviderName.Oracle:
OracleTools.AutoDetectProvider = true;
provider = ProviderName.OracleManaged;
break;
case ProviderName.PostgreSQL:
PostgreSQLTools.AutoDetectProvider = true;
break;
case ProviderName.Sybase:
provider = ProviderName.SybaseManaged;
break;
case ProviderName.SqlCe:
{
if (!RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
{
Console.Error.WriteLine($"SQL Server Compact Edition not supported on non-Windows platforms");
return(null);
}
var assemblyPath = providerLocation ?? Path.Combine(Environment.GetEnvironmentVariable(IntPtr.Size == 4 ? "ProgramFiles(x86)" : "ProgramFiles") !, @"Microsoft SQL Server Compact Edition\v4.0\Private\System.Data.SqlServerCe.dll");
if (!File.Exists(assemblyPath))
{
Console.Error.WriteLine(@$ "Cannot locate Server Compact Edition installation.
Probed location: {assemblyPath}.
Possible reasons:
1. SQL Server CE not installed => install SQL CE runtime (e.g. from here https://www.microsoft.com/en-us/download/details.aspx?id=30709)
2. SQL Server CE runtime architecture doesn't match process architecture => add '--architecture x86' or '--architecture x64' scaffold option
3. SQL Server CE runtime has custom location => specify path to System.Data.SqlServerCe.dll using '--provider-location <path_to_assembly>' option");
return(null);
}
var assembly = Assembly.LoadFrom(assemblyPath);
DbProviderFactories.RegisterFactory("System.Data.SqlServerCe.4.0", assembly.GetType("System.Data.SqlServerCe.SqlCeProviderFactory") !);
break;
}
case ProviderName.SapHana:
{
var isOdbc = connectionString.Contains("HDBODBC", StringComparison.OrdinalIgnoreCase);
if (!isOdbc && !RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
{
Console.Error.WriteLine($"Only ODBC provider for SAP HANA supported on non-Windows platforms. Provided connection string doesn't look like HANA ODBC connection string.");
return(null);
}
provider = isOdbc ? ProviderName.SapHanaOdbc : ProviderName.SapHanaNative;
if (!isOdbc)
{
var assemblyPath = providerLocation ?? Path.Combine(Environment.GetEnvironmentVariable(IntPtr.Size == 4 ? "ProgramFiles(x86)" : "ProgramFiles") !, @"sap\hdbclient\dotnetcore\v2.1\Sap.Data.Hana.Core.v2.1.dll");
if (!File.Exists(assemblyPath))
{
Console.Error.WriteLine(@$ "Cannot locate SAP HANA native client installation.
Probed location: {assemblyPath}.
Possible reasons:
1. HDB client not installed => install HDB client for .net core
2. HDB architecture doesn't match process architecture => add '--architecture x86' or '--architecture x64' scaffold option
3. HDB client installed at custom location => specify path to Sap.Data.Hana.Core.v2.1.dll using '--provider-location <path_to_assembly>' option");
return(null);
}
var assembly = Assembly.LoadFrom(assemblyPath);
DbProviderFactories.RegisterFactory("Sap.Data.Hana", assembly.GetType("Sap.Data.Hana.HanaFactory") !);
}
break;
}
case ProviderName.Informix:
case ProviderName.DB2:
{
if (provider == ProviderName.Informix)
{
provider = ProviderName.InformixDB2;
}
else
{
DB2Tools.AutoDetectProvider = true;
}
if (providerLocation == null || !File.Exists(providerLocation))
{
// we cannot add 90 Megabytes (compressed size) of native provider for single db just because we can
// note: we use IBM.Data.DB2.Core because Net.IBM.Data.Db2 and Net5.IBM.Data.Db2 require
// net6/net5 runtime and fail to load if .net core 3.1 runtime used to run tool (default runtime for tool)
Console.Error.WriteLine(@$ "Cannot locate IBM.Data.DB2.Core.dll provider assembly.
Due to huge size of it, we don't include IBM.Data.DB2 provider into installation.
You need to install it manually and specify provider path using '--provider-location <path_to_assembly>' option.
Provider could be downloaded from:
- for Windows: https://www.nuget.org/packages/Net.IBM.Data.DB2.Core
- for Linux: https://www.nuget.org/packages/Net.IBM.Data.DB2.Core-lnx
- for macOS: https://www.nuget.org/packages/Net.IBM.Data.DB2.Core-osx");
return(null);
}
var assembly = Assembly.LoadFrom(providerLocation);
DbProviderFactories.RegisterFactory("IBM.Data.DB2", assembly.GetType($"{assembly.GetName().Name}.DB2Factory") !);
break;
}
case ProviderName.Access:
{
if (!RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
{
Console.Error.WriteLine($"MS Access not supported on non-Windows platforms");
return(null);
}
var isOleDb = connectionString.Contains("Microsoft.Jet.OLEDB", StringComparison.OrdinalIgnoreCase) ||
connectionString.Contains("Microsoft.ACE.OLEDB", StringComparison.OrdinalIgnoreCase);
if (!isOleDb)
{
provider = ProviderName.AccessOdbc;
}
if (additionalConnectionString == null)
{
Console.Out.WriteLine($"WARNING: it is recommended to use '--additional-connection <secondary_connection>' option with Access for better results");
}
else
{
var isSecondaryOleDb = additionalConnectionString.Contains("Microsoft.Jet.OLEDB", StringComparison.OrdinalIgnoreCase) ||
additionalConnectionString.Contains("Microsoft.ACE.OLEDB", StringComparison.OrdinalIgnoreCase);
if (isOleDb == isSecondaryOleDb)
{
Console.Error.WriteLine($"Main and secondary connection strings must use different providers. One should be OLE DB provider and another ODBC provider.");
return(null);
}
var secondaryProvider = isSecondaryOleDb ? ProviderName.Access : ProviderName.AccessOdbc;
var secondaryDataProvider = DataConnection.GetDataProvider(secondaryProvider, additionalConnectionString);
if (secondaryDataProvider == null)
{
Console.Error.WriteLine($"Cannot create database provider '{provider}' for secondary connection");
return(null);
}
secondaryConnection = new DataConnection(secondaryDataProvider, additionalConnectionString);
// to simplify things for caller (no need to detect connection type)
// returned connection should be OLE DB and additional - ODBC
returnSecondary = isSecondaryOleDb;
}
break;
}
default:
Console.Error.WriteLine($"Unsupported database provider: {provider}");
return(null);
}
var dataProvider = DataConnection.GetDataProvider(provider, connectionString);
if (dataProvider == null)
{
Console.Error.WriteLine($"Cannot create database provider: {provider}");
secondaryConnection?.Dispose();
return(null);
}
var dc = new DataConnection(dataProvider, connectionString);
if (secondaryConnection != null && returnSecondary)
{
var tmp = secondaryConnection;
secondaryConnection = dc;
return(tmp);
}
return(dc);
}
internal DataReaderWrapper(DataConnection dataConnection, DbDataReader dataReader, DbCommand?command)
{
_dataConnection = dataConnection;
DataReader = dataReader;
Command = command;
}