Couchbase 5.0, as of its March 2017 Developer build, introduced significant performance enhancements to N1QL, particularly through index projection, improved handling of COUNT(DISTINCT), and the integration of ORDER BY, LIMIT, and OFFSET operators. Index projection allows queries to focus on specific keys within an index, reducing the need for additional network, CPU, and memory resources. This change marks a departure from previous versions where all keys were considered regardless of necessity, enhancing efficiency. For COUNT(DISTINCT) operations, processing is now offloaded to the indexer rather than the N1QL service, yielding performance benefits. Moreover, the inclusion of ORDER BY and OFFSET in the indexer, alongside LIMIT, streamlines operations by limiting the need to process unnecessary data. These advancements collectively aim to improve the scalability and performance of Couchbase Server clusters.