feat: add SQLDB() to get the underlying database/sql.(*DB) from a store

db.go

@@ -11,6 +11,10 @@ type dB struct {
 	*sqlx.DB
 }
 
+func (db *dB) SQLDB() *sql.DB {
+	return db.DB.DB
+}
+
 func (db *dB) TransactionContext(ctx context.Context) (*Tx, error) {
 	return newTX(ctx, db, nil)
 }

store.go

@@ -21,6 +21,8 @@ type store interface {
 	Commit() error
 	Close() error
 
+	SQLDB() *sql.DB
+
 	// Context versions to wrap with contextStore
 	SelectContext(context.Context, interface{}, string, ...interface{}) error
 	GetContext(context.Context, interface{}, string, ...interface{}) error

tx.go

@@ -18,11 +18,13 @@ func init() {
 type Tx struct {
 	ID int
 	*sqlx.Tx
+	db *sql.DB
 }
 
 func newTX(ctx context.Context, db *dB, opts *sql.TxOptions) (*Tx, error) {
 	t := &Tx{
 		ID: rand.Int(),
+		db: db.SQLDB(),
 	}
 	tx, err := db.BeginTxx(ctx, opts)
 	t.Tx = tx
@@ -32,6 +34,10 @@ func newTX(ctx context.Context, db *dB, opts *sql.TxOptions) (*Tx, error) {
 	return t, nil
 }
 
+func (tx *Tx) SQLDB() *sql.DB {
+	return tx.db
+}
+
 // TransactionContext simply returns the current transaction,
 // this is defined so it implements the `Store` interface.
 func (tx *Tx) TransactionContext(ctx context.Context) (*Tx, error) {