H2

Use JdbcTemplate, method annotations, Mapper files, or the Builder API with H2. The following pages cover database-specific configuration and usage.

Scenario	Usage
Key generation	IDENTITY and sequences
Pagination	LIMIT / OFFSET
Insert conflicts	MERGE

• Programmatic API: queries, writes, multiple results, and stored routine differences.
• Mapper API: annotations, Mapper reads and writes, and execution differences.
• Builder API: Supported operations, datasource-specific behavior, and usage.
• Pagination: Page queries and total counts.
• Insert Conflicts: Handle existing records during insertion.
• Key Generation: Configure and retrieve IDs.
• Type Support: Choose Java property types.
• Transaction Support: Roll back multiple writes on failure.

For an in-memory database, use jdbc:h2:mem:demo;DB_CLOSE_DELAY=-1. This keeps its data until the JVM exits. See Core API for common operations.