511-frameworks-micronaut-jdbc
Micronaut JDBC — programmatic SQL
Apply programmatic JDBC patterns in Micronaut with safe SQL and clear transactions.
What is covered in this Skill?
- Injected javax.sql.DataSource (Hikari-backed with micronaut-jdbc-hikari) and try-with-resources for Connection / PreparedStatement
- PreparedStatement with bind parameters — never string concatenation
- Mapping ResultSet rows to Java records (dedicated mapRow method)
- Safe single-row queries with Optional; never assume rs.next() succeeds
- SQLException translation to domain exceptions (catch-translate-rethrow)
- Streaming large result sets with setFetchSize to avoid OOM
- Batch updates with addBatch / executeBatch for bulk inserts
- @Transactional service boundaries and TransactionDefinition.Propagation (e.g. REQUIRES_NEW for independent commits)
- Self-invocation pitfall: call transactional collaborators through injected beans, not this.method()
- SQL text blocks for multi-line SQL (upserts, dialect-specific clauses)
- When to prefer Micronaut Data (
@512) vs raw JDBC
Scope: Apply recommendations based on the reference rules and good/bad code examples.
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