Just trying to validate this is a good approach.We currently have a union
schema that we use to define a simple data item of type "any" (like the old
COM Variant):
{"name": "item", "type": [ "double", "float", "int", "long", "string",
"DateTime", "null"] }
I'd like to add another union member that works like "null", in that no
data ever gets written except the union discriminator itself. We are
streaming time-series data, and this value would have a special meaning of
"value is unchanged". I could make it an enum with just one value, but then
you would write at least two bytes. So I'm thinking I can make a record:
{
"type": "record",
"name": "Unchanged",
"fields":
[
{ "name": "item", "type": "null" }
]
}
and then my union becomes
{
"name": "item", "type": [ "double", "float", "int", "long", "string",
"DateTime", "null", Unchanged]
}
Seem reasonable?
