arangosh> db.ids.ensureUniqueSkiplist("name.first", "name.last"); { "id" : "ids/1118558663", "type" : "skiplist", "fields" : [ "name.first", "name.last" ], "unique" : true, "sparse" : false, "isNewlyCreated" : true, "code" : 201 } arangosh> db.ids.save({ "name" : { "first" : "hans", "last": "hansen" }}); { "_id" : "ids/1118886343", "_rev" : "1118886343", "_key" : "1118886343" } arangosh> db.ids.save({ "name" : { "first" : "jens", "last": "jensen" }}); { "_id" : "ids/1119082951", "_rev" : "1119082951", "_key" : "1119082951" } arangosh> db.ids.save({ "name" : { "first" : "hans", "last": "jensen" }}); { "_id" : "ids/1119279559", "_rev" : "1119279559", "_key" : "1119279559" } [ArangoError 1210: cannot create document, unique constraint violated]