StackExchange/Dapper
Dapper
Dapper is a high-performance micro-ORM and SQL object mapper for .NET. It functions as an ADO.NET extension library that adds data mapping capabilities directly to database connections, allowing SQL query results to be transformed into typed objects.
The project prioritizes execution speed and low memory overhead by using intermediate language generation to map database columns to object properties. It further optimizes performance through the use of concurrent caching for mapping functions and literal value injection to improve database execution plans.
The library covers a broad range of data access capabilities, including synchronous and asynchronous SQL command execution, stored procedure support, and multi-mapping for relational data. It includes tools for managing dynamic parameters, processing multiple result sets, and streaming large datasets row-by-row to minimize memory consumption.
Features
- SQL Query Execution - Executes synchronous and asynchronous SQL statements, including single operations and bulk updates with parameter collections.
- Micro-ORMs - Functions as a high-performance micro-ORM for the .NET ecosystem.
- ADO.NET Extensions - Extends the IDbConnection interface with methods that simplify SQL command and stored procedure execution.
- .NET Database Integration - Connects .NET applications to SQL databases to execute queries and retrieve data using typed objects.
- Parameter Collections - Transforms anonymous objects into database parameter collections by iterating over properties at runtime.
- Object-Relational Mapping - Provides a lightweight object-relational mapping layer for common create, read, update, and delete operations.
- Dynamic Mapping Engines - Generates Intermediate Language code at runtime to achieve high-performance mapping between database columns and object properties.
- Dynamic Parameter Injection - Extracts parameters from objects or constructs them dynamically to support adaptive query building.
- Result Converters - Transforms raw database query results into typed objects or dynamic lists.
- Object Mappers - Automates the translation of database result sets into strongly-typed C# application objects.
- Extension Methods - Provides database mapping capabilities as extensions to the standard IDbConnection interface.
- Concurrent Caches - Uses concurrent caches to store generated mapping functions and avoid redundant compilation of query logic.
- Multi-Object Row Deserialization - Deserializes a single database row into several distinct objects to handle joined data and associations.
- Memory-Optimized Data Retrieval - Fetches large datasets from a database with minimal memory overhead using row streaming and optimized mapping.
- Result Parsing Optimizations - Prioritizes execution speed and low memory overhead using runtime IL generation for result parsing.
- Result Streaming - Supports row-by-row processing of query results to minimize memory consumption when handling large datasets.
- Collection-Based Filtering - Automatically parameterizes queries using collections to filter results based on multiple provided values.
- Multi-Result Set Parsers - Supports executing a single query that returns multiple data grids and processing each set independently.
- Row-Based Result Streaming - Reads database results one record at a time to minimize memory usage when handling large datasets.
- Stored Procedures - Executes database stored procedures and maps the returned data sets into typed objects.
- Multi-Object Row Splitting - Splits a single database row into multiple distinct objects based on specified column split points.
- Object Relational Mapping - High-performance micro-ORM for mapping database results to objects.
- Persistence Frameworks - Lightweight object mapper for .NET.
