Yugabytedb app dev

YugabyteDB Application Development Skill

A reference skill for building applications on top of YugabyteDB, covering connection config, transaction retries, and language/framework-specific best practices.

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Overview

YugabyteDB is a distributed SQL database compatible with PostgreSQL. Writing applications for it requires attention to three areas standard Postgres apps often skip:

1. Driver — Use the YugabyteDB JDBC driver (jdbc-yugabytedb) or the standard Postgres driver. YB's driver adds cluster-aware load balancing and topology routing.
2. Retries — Distributed transactions can fail with transient errors (serialization failures 40001, deadlocks 40P01, connection resets). Applications MUST retry these rather than surface them to users.

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Quick Reference by Runtime

Runtime	Driver / Library	Retry Mechanism
Java / Spring Boot	jdbc-yugabytedb + HikariCP	Spring core RetryPolicy + ExponentialBackOff (built-in, no extra dep) + AOP aspect
Java / Spring Boot Reactive	r2dbc-postgresql + r2dbc-pool	Reactor .retryWhen(YbRetry.spec()) inline in pipeline
Java / Quarkus	jdbc-yugabytedb + Agroal	SmallRye @Retry + CDI interceptor for exception translation
Python	psycopg2 / asyncpg	Custom decorator wrapping psycopg2.errors.SerializationFailure
Node.js	@yugabytedb/pg (smart driver)	withRetry loop catching 40001/40P01/XX000
Go	pgx	pgx retry loop
.NET / ASP.NET Core	Npgsql + EF Core	Polly AsyncRetryPolicy

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Instructions

• Use the latest stable version of the YugabyteDB driver for your language
• Use the latest stable version of the application framework for your language

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Core Concepts

Transaction Error Codes to Retry

40001  — serialization_failure (optimistic concurrency)
40P01  — deadlock_detected
57P01  — admin_shutdown (node restart / kill -15)
08006  — connection_failure (socket timeout, kill -9)
XX000  — internal_error — ONLY retry conditionally

Also retry on these Java exception types for JPA/JDBC:

• SQLRecoverableException
• SQLTransientConnectionException
• TransientDataAccessException
• Hibernate TransactionException (begin/commit/rollback failures)

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Java References

Spring Boot

For full details read → references/java-spring.md

Key files in the reference implementation:

File	Purpose
KVRetryPolicy.java	Implements RetryPolicy — classifies retryable exceptions; owns ExponentialBackOff
DataSourceAspect.java	AOP aspect wrapping all @Service methods with RetryTemplate
YbDataApplication.java	Wires RetryTemplate with exponential backoff from config
KVService.java	Service using @Transactional and @Transactional(readOnly = true)
application.yaml	Full driver + pool + retry config

Spring Boot Reactive (WebFlux + R2DBC)

For full details read → references/java-spring-reactive.md

Key differences from Spring Boot (blocking):

Topic	Reactive behaviour
Driver	com.yugabyte:r2dbc-postgresql (YugabyteDB fork) — URL scheme r2dbc:postgresql://
Retry	RetryConfigSpec bean provides Retry; controller applies .retryWhen(retrySpec) on each pipeline
Transactions	@Transactional in service; retry wraps outside via controller pipeline
Migrations	Flyway still runs over JDBC at startup (add jdbc-yugabytedb as a side-car dep)

Quarkus

For full details read → references/java-quarkus.md

Key differences from Spring Boot:

Topic	Quarkus behaviour
Connection pool	Agroal (not HikariCP); config via quarkus.datasource.jdbc.*
Retry mechanism	SmallRye Fault Tolerance @Retry + custom CDI interceptor for SQL-state translation
Interceptor ordering	CRITICAL: set mp.fault.tolerance.interceptor.priority=100 so @Retry wraps outside @Transactional, giving each retry a fresh transaction
Native image	YugabyteDB driver is JVM-mode only — not compatible with GraalVM native compilation

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Python Reference

For full details read → references/python.md

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Node.js Reference

For full details read → references/nodejs.md

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Go Reference

For full details read → references/go.md

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.NET Reference

For full details read → references/dotnet.md

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Step-by-Step: New Application Setup

1. Add Dependencies

Maven (Java):

<dependency>
  <groupId>com.yugabyte</groupId>
  <artifactId>jdbc-yugabytedb</artifactId>
  <version>42.7.3-yb-4</version>
</dependency>
<dependency>
  <groupId>org.springframework.retry</groupId>
  <artifactId>spring-retry</artifactId>
  <version>2.0.12</version>
</dependency>

Python:

pip install psycopg2-binary  # or asyncpg for async

Node.js:

npm install @yugabytedb/pg    # YugabyteDB smart driver (fork of node-postgres)

Go:

go get github.com/jackc/pgx/v5

2. Configure Datasource

Always set:

• auto-commit: false — YugabyteDB works best with explicit transaction management
• connection-init-sql with prepare warmup; execute warmup; commit; — validates and warms the connection
• socketTimeout — prevents hanging connections on node failure
• yb-servers-refresh-interval — refreshes cluster topology periodically

3. Implement Retry Logic

Never skip retries. YugabyteDB distributed transactions can fail with 40001 under normal operation (two concurrent writers hitting the same row). Without retries, these surface as errors to end users.

Use the reference KVRetryPolicy pattern — read references/java-spring.md for the full annotated implementation with all retry-worthy SQL states.

4. Schema Migrations

Use Flyway (Java) or Alembic (Python) for schema management. YugabyteDB supports all standard PostgreSQL DDL.

-- Example migration: V1_0_0__create.sql
CREATE EXTENSION IF NOT EXISTS "uuid-ossp";
CREATE TABLE IF NOT EXISTS kvinfo (
    key   uuid PRIMARY KEY,
    value text
);   -- tune tablet count to expected data size

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Common Pitfalls

Pitfall	Fix
Not retrying 40001	Always wrap service layer with retry
auto-commit: true	Set to false; manage transactions explicitly
Using standard org.postgresql driver	Use com.yugabyte driver for topology-aware load balancing
Missing socketTimeout	Connections can hang indefinitely on node failure without it
Forgetting @Transactional on service methods	Without it, each repo call is its own transaction; retries won't help multi-step operations

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Sample Prompts

These are example prompts that should trigger this skill.

Java / Spring Boot

• "I'm building a Spring Boot app and need to connect it to YugabyteDB. Show me the Maven dependencies, application.yaml config, and how to set up the connection pool correctly."
• "My Spring Boot app talking to YugabyteDB keeps getting '40001 serialization failure' errors under load. How do I handle this properly?"
• "I have an existing Spring Boot app connected to PostgreSQL. What do I need to change to migrate it to YugabyteDB?"

Java / Spring Boot Reactive

• "How do I build a reactive Spring Boot application using WebFlux and R2DBC that connects to YugabyteDB with retry support?"

Java / Quarkus

• "I want to build a Quarkus REST API backed by YugabyteDB. Walk me through the setup including retry handling."
• "My Quarkus app has @Retry on the service but transactions still fail without retrying. What's wrong?"

Python

• "How do I write a Python service that connects to YugabyteDB and handles transaction retries correctly? I need create, read, and delete operations."
• "Show me how to use asyncpg with FastAPI and YugabyteDB with proper retry handling."

Node.js

• "Show me how to connect a Node.js Express app to YugabyteDB with proper retry logic for distributed transaction errors."

Go

• "I'm using Go with pgx and need to connect to YugabyteDB and retry on transaction conflicts. Show me a complete example."

.NET

• "How do I set up a .NET ASP.NET Core app with Entity Framework Core to use YugabyteDB, including handling serialization failures?"

General / Cross-runtime

• "What SQL error codes do I need to retry on when using YugabyteDB, and why?"
• "How should I configure my connection pool for YugabyteDB?"
• "Connect my app to YugabyteDB"
• "YugabyteDB retry"
• "YugabyteDB Spring Boot setup"