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Failover Store Query Resolver

Failover Store Query Resolver

FailoverStoreQueryResolver overrides the SQL queries used by the JDBC store. Use this when you need schema-qualified table names, custom column mappings, or database-specific query optimisations.

Interface

public interface FailoverStoreQueryResolver<T> {
    String storeQuery(String tableName);
    String findQuery(String tableName);
    String deleteQuery(String tableName);
    String cleanByExpiryQuery(String tableName);
    RowMapper<ReferentialPayload<T>> rowMapper();
}

Each method receives the computed tableName (including prefix) and returns the SQL string for that operation.

When to Use

  • Table is in a non-default schema: MY_SCHEMA.FAILOVER_STORE
  • Custom column names or types
  • Database-specific hints or query syntax not covered by the default dialect detection

Step 1 — Implement FailoverStoreQueryResolver

SchemaQualifiedQueryResolver.java
@Component
public class SchemaQualifiedQueryResolver<T> implements FailoverStoreQueryResolver<T> {

    private final String schema;

    public SchemaQualifiedQueryResolver(@Value("${db.schema:PUBLIC}") String schema) {
        this.schema = schema;
    }

    @Override
    public String storeQuery(String tableName) {
        return "MERGE INTO " + schema + "." + tableName +
               " (FAILOVER_NAME, FAILOVER_KEY, AS_OF, EXPIRE_ON, PAYLOAD, PAYLOAD_CLASS)" +
               " KEY (FAILOVER_NAME, FAILOVER_KEY)" +
               " VALUES (?, ?, ?, ?, ?, ?)";
    }

    @Override
    public String findQuery(String tableName) {
        return "SELECT * FROM " + schema + "." + tableName +
               " WHERE FAILOVER_NAME = ? AND FAILOVER_KEY = ?";
    }

    @Override
    public String deleteQuery(String tableName) {
        return "DELETE FROM " + schema + "." + tableName +
               " WHERE FAILOVER_NAME = ? AND FAILOVER_KEY = ?";
    }

    @Override
    public String cleanByExpiryQuery(String tableName) {
        return "DELETE FROM " + schema + "." + tableName +
               " WHERE EXPIRE_ON < ?";
    }

    @Override
    public RowMapper<ReferentialPayload<T>> rowMapper() {
        return null;   // null = use default row mapper
    }
}

Next Steps