When saving an updated node, does the update operation clear all caches? Just want to confirm when a node is updated, the update operation clears the complete cache table or the updated node related cache contents. Is this right?
There is only one line about clearing cache in node_save():

// Clear the static loading cache.
entity_get_controller('node')-&gt;resetCache(array($node-&gt;nid));


It only resets entity-related cache. Caches related to another nodes, caches like boost and so on are left untouched, unless specifically cleared by other module's actions in node or entity saving hooks.