arangosh> db.test.ensureHashIndex("a");
{
"id" : "test/1174315564",
"type" : "hash",
"fields" : [
"a"
],
"selectivityEstimate" : 1,
"unique" : false,
"sparse" : false,
"isNewlyCreated" : true,
"code" : 201
}
arangosh> db.test.save({ a : 1 });
{
"_id" : "test/1174577708",
"_rev" : "1174577708",
"_key" : "1174577708"
}
arangosh> db.test.save({ a : 1 });
{
"_id" : "test/1174774316",
"_rev" : "1174774316",
"_key" : "1174774316"
}
arangosh> db.test.save({ a : null });
{
"_id" : "test/1175036460",
"_rev" : "1175036460",
"_key" : "1175036460"
}