arangosh> db.test.ensureIndex({ type: "hash", fields: [ "a" ] });
{
"deduplicate" : true,
"fields" : [
"a"
],
"id" : "test/74474",
"isNewlyCreated" : true,
"name" : "idx_1646382081936195584",
"selectivityEstimate" : 1,
"sparse" : false,
"type" : "hash",
"unique" : false,
"code" : 201
}
arangosh> db.test.save({ a : 1 });
{
"_id" : "test/74478",
"_key" : "74478",
"_rev" : "_ZXF6dUW--_"
}
arangosh> db.test.save({ a : 1 });
{
"_id" : "test/74480",
"_key" : "74480",
"_rev" : "_ZXF6dUa---"
}
arangosh> db.test.save({ a : null });
{
"_id" : "test/74482",
"_key" : "74482",
"_rev" : "_ZXF6dUa--A"
}