CockroachDB Driver

CockroachDB support follows PostgreSQL-like SQL syntax, with CockroachDB's serializable transaction behavior.

Packages

import (
    "database/sql"

    "github.com/dmedovich/queen"
    "github.com/dmedovich/queen/drivers/cockroachdb"
    _ "github.com/jackc/pgx/v5/stdlib"
)

db, err := sql.Open("pgx", os.Getenv("DATABASE_URL"))
if err != nil {
    return err
}

driver, err := cockroachdb.New(db)
if err != nil {
    return err
}

q := queen.New(driver)

How it works

Area	Implementation
Migration table	SQL table with metadata columns.
Lock table	Separate <table>_lock table with lock_key primary key and expires_at.
Identifier quoting	Double quotes.
Placeholders	$1, $2, ...
Lock owner	Generated owner ID per driver instance.
Locking	Table-backed lock through cleanup, check, and insert.
Unlock	Deletes the lock row for the current owner.
Execution	database/sql transaction through the shared base driver.
Atomic record	Yes. RecordTx and RemoveTx run with the migration body.

Guarantees

• Lock rows expire and are cleaned during acquisition attempts.
• Wrapped sql.ErrNoRows is treated as no active lock.
• Queen uses natural status ordering before planning operations.

Limitations

• CockroachDB can return retryable serialization errors (40001).
• The driver retries 40001 serialization failures up to three times; Go callbacks must be safe to run again.
• Migration metadata is written in the same transaction as the migration body.

Operational advice

• Run one migrator job per environment.
• If retries are exhausted, inspect the migration record and schema before rerunning the migrator.
• Prefer PostgreSQL for the first production target when you need Queen's strongest guarantees today.