* though certain objects may assume READ_LATEST for common use case or legacy reasons.
*
* There are four types of reads:
- * - READ_NORMAL : Potentially cached read of data (e.g. from a slave or stale replica)
+ * - READ_NORMAL : Potentially cached read of data (e.g. from a replica DB or stale replica)
* - READ_LATEST : Up-to-date read as of transaction start (e.g. from master or a quorum read)
* - READ_LOCKING : Up-to-date read as of now, that locks (shared) the records
* - READ_EXCLUSIVE : Up-to-date read as of now, that locks (exclusive) the records
* All record locks persist for the duration of the transaction.
*
* A special constant READ_LATEST_IMMUTABLE can be used for fetching append-only data. Such
- * data is either (a) on a slave and up-to-date or (b) not yet there, but on the master/quorum.
- * Because the data is append-only, it can never be stale on a slave if present.
+ * data is either (a) on a replica DB and up-to-date or (b) not yet there, but on the master/quorum.
+ * Because the data is append-only, it can never be stale on a replica DB if present.
*
* Callers should use READ_NORMAL (or pass in no flags) unless the read determines a write.
* In theory, such cases may require READ_LOCKING, though to avoid contention, READ_LATEST is
*/
interface IDBAccessObject {
/** Constants for object loading bitfield flags (higher => higher QoS) */
- /** @var integer Read from a slave/non-quorum */
+ /** @var int Read from a replica DB/non-quorum */
const READ_NORMAL = 0;
- /** @var integer Read from the master/quorum */
+ /** @var int Read from the master/quorum */
const READ_LATEST = 1;
- /* @var integer Read from the master/quorum and lock out other writers */
+ /* @var int Read from the master/quorum and lock out other writers */
const READ_LOCKING = 3; // READ_LATEST (1) and "LOCK IN SHARE MODE" (2)
- /** @var integer Read from the master/quorum and lock out other writers and locking readers */
+ /** @var int Read from the master/quorum and lock out other writers and locking readers */
const READ_EXCLUSIVE = 7; // READ_LOCKING (3) and "FOR UPDATE" (4)
- /** @var integer Read from a slave/non-quorum immutable data, using the master/quorum on miss */
+ /** @var int Read from a replica DB or without a quorum, using the master/quorum on miss */
const READ_LATEST_IMMUTABLE = 8;
// Convenience constant for tracking how data was loaded (higher => higher QoS)