Net4x.DapperLibrary.SqlServer 1.9.9

DapperLibrary.SqlServer

SQL Server provider-specific extensions for DapperLibrary. This project contains the SQL Server concrete SqlDapperContext, the SqlProviderFactory and SQL Server specific database model types and helpers such as restore-from-backup extensions.

Purpose

Provide SQL Server engine-specific behavior and defaults while keeping the DapperLibrary public API consistent across providers. This includes:

• A SqlDapperContext that wires SQL Server-specific defaults into DapperContext.
• A SqlProviderFactory that configures data adapter behavior, parameter handling and row update events.
• SqlDatabaseModel with SQL Server delimiters, parameter prefix and type mappings.
• Helpers for administrative tasks (for example RestoreDatabaseFromBackupAsync).

Key types

• SqlDapperContext � derived DapperContext configured for SQL Server. Convenience static Use / UseOnce methods register a ContextCreator that sets SQL Server defaults (for instance IdentityInitializer and FormatDatetimeAsString). Constructors accept DapperConnectionStringSettings or IConfiguration.

• SqlProviderFactory � provider factory based on the underlying SQL client factory (System.Data.SqlClient on older frameworks or Microsoft.Data.SqlClient on newer). It sets ParameterModel.AddIndex = true and installs a PrepareCommandParameters delegate. It also exposes row-updating/updated event raising hooks.

• SqlDatabaseModel � implements DatabaseModel specifics for SQL Server (begin/end delimiters [ / ], batch separator GO, parameter prefix @, and SQL Server-specific type mappings).

• RestoreExtension � utility extension providing RestoreDatabaseFromBackupAsync which reads backup logical names, computes file move clauses and executes a restore statement. It demonstrates safe closing of open readers and connections and updates the context's active connection string to point at the restored database.

Usage

Create and use a SqlDapperContext as you would a DapperContext, or use the static helpers to wire convenient context creation:

// Simple: create from defaults
using var context = new SqlDapperContext();

// Register usage factory in bootstrap code
SqlDapperContext.Use();

// Use a single use creator with explicit connection string
SqlDapperContext.UseOnce(connectionString, providerName);

Customize identity and datetime formatting when using the static helpers (these are set automatically by the Use helpers):

// The created context will have: DatabaseModel.IdentityInitializer = "IDENTITY(int, 1, 1)"
// and a FormatDatetimeAsString that produces CONVERT(datetime, '...') SQL compatible with SQL Server.

Restore database example:

await context.RestoreDatabaseFromBackupAsync("MyNewDb", @"C:\Backups\mydb.bak");

Restore will close any open readers and connections used by the DapperContext and update the context's ConnectionStringSettings to point to the restored database.

Multi-targeting & client compatibility

• The code contains conditional compilation to support older .NET Framework targets and modern .NET runtimes. The SQL client implementation chosen depends on the target framework:
  • On older targets (NET35, NET40, NET45, NET461, etc.) the project uses System.Data.SqlClient.
  • On newer targets the project uses Microsoft.Data.SqlClient.
• NuGet artifacts produced from this source will include framework-specific assemblies and the appropriate SQL client dependency for each target.

Synchronous vs asynchronous behavior

• SqlDapperContext and the underlying DapperContext expose both synchronous and asynchronous operations. Use the Async-suffixed methods for non-blocking I/O (for example GetDataReaderAsync, SetDataAsync, GetDataTableAsync).
• RestoreDatabaseFromBackupAsync is implemented as an async operation and uses async reader/close patterns where available; conditional compilation guards are present to handle frameworks that do not expose certain CloseAsync or ReadAsync APIs.

Events and adapters

• SqlProviderFactory.CreateDataAdapter attaches to RowUpdated/RowUpdating events and forwards them via the provider factory's raised events. This allows consumer code to react to row update lifecycle events when using DbDataAdapter operations (for example when using SaveDataTable).

Notes and best practices

• Prefer the Use / UseOnce static helpers when wiring SQL Server contexts�these helpers preconfigure common SQL Server behaviors.
• When running restore or other administrative operations, ensure the process has sufficient permissions and that no external process is locking the target files.
• Use async APIs in server applications to avoid blocking thread-pool threads.

For further details consult the source files in DbContexts and Extensions directories.