queryIterator limit field is not documented properly

[teynar]

According to this README.md:

limit: total, // optional, how much data do you want to fetch, if not set, fetch all the data, be careful if you have large data set

https://github.com/milvus-io/milvus-sdk-node/blame/9d4cc1beb11b554902bc57c2d96f9c817b0aff58/README.md#L72-L94

It says this field is optional, but in reality, it is currently required as shown here:

milvus-sdk-node/milvus/types/Data.ts

Lines 419 to 423 in 9d4cc1b

	export interface QueryIteratorReq
	extends Omit<QueryReq, 'ids' | 'offset' | 'limit'> {
	limit: number;
	batchSize: number;
	}

In the Python SDK, if the limit is set to -1, then it means that there is no limit to the query operation.

Therefore I believe that this should be done:

Optionally set an exported constant for the -1 value (NO_LIMIT) for users to use which is considered in the typescript type

And do one of these options:
a) Update this piece of documentation and state that -1 means "no limit", refer to the constant if it exists
b) Allow the limit field to be not defined and default to -1 as "no limit", refer to the constant if it exists

[shanghaikid]

you are right, my bad, I will fix this tomorrow.