What is cockroachdb-app-patterns?

A set of coding rules for building applications that use CockroachDB, a distributed SQL database. It covers transactions, database connections, schemas, online changes, batching, and multi-region setups.

Use it when writing or reviewing application code that reads from or writes to CockroachDB, including database models, migrations, connection pools, and transaction handling.

It helps prevent errors caused by concurrent transactions, dropped connections, unsafe schema changes, and incorrect database settings.

cockroachdb-app-patterns — Cursor rule by cockroachdb

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods

npx agentmods add rules/cockroachdb/cursor-plugin/cockroachdb-app-patterns

Clone the repo

git clone --depth 1 https://github.com/cockroachdb/cursor-plugin

Per session 0 Nothing until a file matches its globs; then the whole rule loads.

When invoked 6,340 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. Scan, not verified.

Origin original No closer match found in the catalogue.

Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

Model	Per session	Once invoked
Fable 5	$0.00000	$0.06340
Opus 5	$0.00000	$0.03170
Sonnet 5	$0.00000	$0.01268
Haiku 4.5	$0.00000	$0.00634

Measured yesterday against content hash 2358f773451f, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

cockroachdb-app-patterns scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

rules/cockroachdb-app-patterns.mdc · 714 lines

How it starts

The opening of the file, as written. The whole thing — 714 lines — stays where its author put it; the contents beside it link to each section on GitHub.

CockroachDB Application Patterns

These rules encode production-tested patterns from cockroachdb-best-practices-demo and cockroachdb-jdbc-wrapper. Follow them strictly when generating code that interacts with CockroachDB.

1. Transaction Retry Logic (MANDATORY)

CockroachDB defaults to SERIALIZABLE isolation — the strongest level. This means any two concurrent transactions touching the same rows may produce a SQLSTATE 40001 (serialization failure). Applications MUST implement retry logic.

Retryable Error Codes

SQLSTATE	Meaning	Action
`40001`	Serialization failure (transaction conflict)	ALWAYS retry the entire transaction
`08001`	Unable to establish connection	Retry with backoff
`08003`	Connection does not exist	Retry with new connection
`08004`	Connection rejected by server	Retry with backoff
`08006`	Connection failure during transaction	Retry with new connection
`08007`	Transaction resolution unknown	Retry with new connection
`08S01`	Communication link failure	Retry with new connection
`57P01`	Admin shutdown (node drain/restart)	Retry with backoff

Retry Strategy

Use exponential backoff with jitter (not fixed delays)
Recommended: base 200ms, multiplier 2×, jitter factor 0.5
Max attempts: 3–5 for interactive, 5–10 for background/batch
Retry the ENTIRE transaction — not just the failed statement

⛔ ANTI-PATTERN: Savepoint-Based Retry

// ❌ WRONG — This does NOT work with CockroachDB
conn.setAutoCommit(false);
Savepoint sp = conn.setSavepoint("cockroach_restart");
try {
    // ... SQL operations ...
    conn.commit();
} catch (SQLException e) {
    if ("40001".equals(e.getSQLState())) {
        conn.rollback(sp);  // ❌ CockroachDB aborts the ENTIRE txn on 40001
        // retrying here is USELESS — the transaction is dead
    }
}

Read the full file on GitHub · 714 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

yesterday First seen · 714 lines · 0 tokens per session scan A 2358f773451f

Subscribe to this mod's changes

cockroachdb-app-patterns is a cursor rule published in the GitHub repository cockroachdb/cursor-plugin (1 stars, last pushed 1mo ago), licensed Apache-2.0. It costs nothing until one of its globs matches a file; then it loads 6,340 tokens. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Databases Writing and docs cockroach-cloud cockroachdb cursor developer-tools

cockroachdb-app-patterns

Getting it into your agent

What it costs to keep this loaded

Grade A, and why

Nothing flagged

How it starts

CockroachDB Application Patterns

1. Transaction Retry Logic (MANDATORY)

Retryable Error Codes

Retry Strategy

⛔ ANTI-PATTERN: Savepoint-Based Retry

What this file has done since we first saw it

Other cursor rules, from other repositories

beanstalk-deploy

archcore-files

dev_workflow

execution

cosmosmith

no-crux-frontmatter