update
[:update <collection> <update-map> <find-options>?]
<count>
[:update :people {:vip true} {"where": ["=" :name "Bob"]}]
1
Updates records in the collection by merging update-map into any records that match find-options. Returns the number of updated records.
If an attribute is present in both update-map and a matching record, the updated record assumes the value from the update-map. If an attribute is valued with nil in the update map, that attribute will not be present in the updated record.
find-options are of the same form as for select queries, except that the "only": option is not recognized.