package store
import (
"context"
"database/sql"
)
type Querier interface {
WithTx(tx *sql.Tx) Querier
// ... add the methods you actually use
}
func InTx(ctx context.Context, db *sql.DB, q Querier, fn func(context.Context, Querier) error) error {
tx, err := db.BeginTx(ctx, &sql.TxOptions{Isolation: sql.LevelReadCommitted})
if err != nil {
return err
}
defer tx.Rollback()
if err := fn(ctx, q.WithTx(tx)); err != nil {
return err
}
return tx.Commit()
}
When using sqlc, the generated query set usually has a WithTx method. I wrap that pattern so business logic can depend on an interface and still run inside a transaction. The key is to keep transaction boundaries explicit while avoiding passing *sql.Tx everywhere. The helper below begins a transaction, creates a transaction-bound querier via WithTx, runs the function, and commits on success. defer tx.Rollback() is the boring safety net that prevents leaked transactions on early returns. In production, I also set an isolation level via sql.TxOptions and I ensure ctx has a deadline so transactions don’t sit open. This is a small abstraction, but it keeps service methods tidy and makes unit testing easier because you can mock the interface.
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disable_ddl_transaction!
def change
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