arangosh> db.test.ensureIndex({ type: "hash", fields: [ "a" ] });
{
"fields" : [
"a"
],
"id" : "test/342511176",
"selectivityEstimate" : 1,
"sparse" : false,
"type" : "hash",
"unique" : false,
"isNewlyCreated" : true,
"code" : 201
}
arangosh> db.test.save({ a : 1 });
{
"_id" : "test/342773320",
"_rev" : "342773320",
"_key" : "342773320"
}
arangosh> db.test.save({ a : 1 });
{
"_id" : "test/342969928",
"_rev" : "342969928",
"_key" : "342969928"
}
arangosh> db.test.save({ a : null });
{
"_id" : "test/343232072",
"_rev" : "343232072",
"_key" : "343232072"
}