query

ctx := context.TODO()
db, err := ydb.Open(ctx, "grpc://localhost:2136/local")
if err != nil {
	fmt.Printf("failed connect: %v", err)
	return
}
defer db.Close(ctx) // cleanup resources
var (
	id    int32  // required value
	myStr string // optional value
)
// Do retry operation on errors with best effort
err = db.Query().Do(ctx, // context manage exiting from Do
	func(ctx context.Context, s query.Session) (err error) { // retry operation
		_, res, err := s.Execute(ctx,
			`SELECT CAST($id AS Uint64) AS id, CAST($myStr AS Text) AS myStr`,
			query.WithParameters(
				query.Param("$id", query.Uint64Value(123)),
				query.Param("$myStr", query.TextValue("test")),
			),
		)
		if err != nil {
			return err // for auto-retry with driver
		}
		defer func() { _ = res.Close() }() // cleanup resources
		for res.NextResultSet(ctx) {       // iterate over result sets
			for res.Next() { // iterate over rows
				err = res.ScanNamed(
					query.Named("id", &id),
					query.Named("myStr", &myStr),
				)
				if err != nil {
					return err // generally scan error not retryable, return it for driver check error
				}
			}
		}
		return res.Err() // return finally result error for auto-retry with driver
	},
	query.WithIdempotent(),
)
if err != nil {
	fmt.Printf("unexpected error: %v", err)
}
fmt.Printf("id=%v, myStr='%s'\n", id, myStr)

ctx := context.TODO()
db, err := ydb.Open(ctx, "grpc://localhost:2136/local")
if err != nil {
	fmt.Printf("failed connect: %v", err)
	return
}
defer db.Close(ctx) // cleanup resources
var (
	id    int32  // required value
	myStr string // optional value
)
// Do retry operation on errors with best effort
err = db.Query().Do(ctx, // context manage exiting from Do
	func(ctx context.Context, s query.Session) (err error) { // retry operation
		_, res, err := s.Execute(ctx,
			`SELECT 42 as id, "my string" as myStr`,
		)
		if err != nil {
			return err // for auto-retry with driver
		}
		defer func() { _ = res.Close() }() // cleanup resources
		for res.NextResultSet(ctx) {       // iterate over result sets
			for res.Next() { // iterate over rows
				if err = res.Scan(&id, &myStr); err != nil {
					return err // generally scan error not retryable, return it for driver check error
				}
			}
		}
		return res.Err() // return finally result error for auto-retry with driver
	},
	query.WithIdempotent(),
)
if err != nil {
	fmt.Printf("unexpected error: %v", err)
}
fmt.Printf("id=%v, myStr='%s'\n", id, myStr)

ctx := context.TODO()
db, err := ydb.Open(ctx, "grpc://localhost:2136/local")
if err != nil {
	fmt.Printf("failed connect: %v", err)
	return
}
defer db.Close(ctx) // cleanup resources
var (
	id    int32  // required value
	myStr string // optional value
)
// Do retry operation on errors with best effort
err = db.Query().DoTx(ctx, // context manage exiting from Do
	func(ctx context.Context, tx query.TransactionActor) (err error) { // retry operation
		res, err := tx.Execute(ctx,
			`SELECT 42 as id, "my string" as myStr`,
		)
		if err != nil {
			return err // for auto-retry with driver
		}
		defer func() { _ = res.Close() }() // cleanup resources
		for res.NextResultSet(ctx) {       // iterate over result sets
			for res.Next() { // iterate over rows
				err = res.ScanNamed(
					query.Named("id", &id),
					query.Named("myStr", &myStr),
				)
				if err != nil {
					return err // generally scan error not retryable, return it for driver check error
				}
			}
		}
		return res.Err() // return finally result error for auto-retry with driver
	},
	query.WithIdempotent(),
	query.WithTxSettings(query.TxSettings(
		query.WithSnapshotReadOnly(),
	)),
)
if err != nil {
	fmt.Printf("unexpected error: %v", err)
}
fmt.Printf("id=%v, myStr='%s'\n", id, myStr)