2. Mapper API

For general usage, see 5.2 Mapper API; shared capabilities are covered in Parameters and Rules and Receiving Results. Status links in the table explain data-source-specific behavior.

Data source	Method Annotations	Mapper Reads and Writes	Key Strategies	Pagination	Execution Options	Calling Builders	Referencing File Mappers	Session Management
MySQL	✓ Supported	✓ Supported	◐ Partial	✓ Supported	✓ Supported	✓ Supported	✓ Supported	✓ Supported
PostgreSQL	✓ Supported	✓ Supported	✓ Supported	✓ Supported	✓ Supported	✓ Supported	✓ Supported	✓ Supported
Oracle	✓ Supported	✓ Supported	◐ Partial	✓ Supported	✓ Supported	✓ Supported	✓ Supported	✓ Supported
SQL Server	✓ Supported	✓ Supported	✓ Supported	✓ Supported	✓ Supported	✓ Supported	✓ Supported	✓ Supported
DB2	✓ Supported	✓ Supported	✓ Supported	✓ Supported	✓ Supported	✓ Supported	✓ Supported	✓ Supported
H2	✓ Supported	✓ Supported	✓ Supported	✓ Supported	✓ Supported	✓ Supported	✓ Supported	✓ Supported
ClickHouse	◐ Partial	◐ Partial	◐ Partial	✓ Supported	✓ Supported	✓ Supported	✓ Supported	✓ Supported
Redis	◐ Partial	✕ Unsupported	◐ Partial	✕ Unsupported	◐ Partial	✕ Unsupported	✓ Supported	✓ Supported
MongoDB	◐ Partial	✓ Supported	◐ Partial	✓ Supported	◐ Partial	✓ Supported	✓ Supported	✓ Supported
ES 6	✓ Supported	◐ Partial	◐ Partial	✓ Supported	◐ Partial	✓ Supported	✓ Supported	✓ Supported
ES 7	✓ Supported	◐ Partial	◐ Partial	✓ Supported	◐ Partial	✓ Supported	✓ Supported	✓ Supported
Milvus	◐ Partial	◐ Partial	◐ Partial	✓ Supported	◐ Partial	✓ Supported	◐ Partial	✓ Supported

• Method annotations: queries, writes, @Execute, multiline command assembly, and error handling.
• Mapper reads and writes: BaseMapper CRUD, replacement, upsert, sample queries, and writes using Map arguments.
• Key strategies: assigned and default keys, generated-key retrieval, selectKey, and composite keys.
• Pagination: method annotations, BaseMapper, and file-mapper calls.
• Execution options: statement mode, timeout, fetch settings, and result-set types, including scrolling.
• Calling builders: obtain and use a builder through a Mapper or Session.
• Referencing file mappers: query, write, and read return values by statement ID.
• Session management: create mappers, reuse sessions, and access data across APIs.