How to Set Limit for options.FindOne() in go mongo-driver-CodePudding

I see there is a way to SetLimit() for Find() func, But I don't see any options to set limit for FindOne() , Since we are searching single result out of FindOne() we don't even have to limit it ? Automatically it handles limit ?

Tried setting limit using 1options.FindOne()` , But I do not see a way to do that .

CodePudding user response：

It's not documented, but it's common sense that Collection.FindOne() implies a behavior of that of Limit=1. The return value of Collection.FindOne() doesn't give access to multiple result documents, that's why options.FindOne doesn't even have a SetLimit() method.

If you check the source code, it's in there:

// Unconditionally send a limit to make sure only one document is returned and the cursor is not kept open
// by the server.
findOpts = append(findOpts, options.Find().SetLimit(-1))

Note that FindOptions.Limit documents that:

// Limit is the maximum number of documents to return. The default value is 0, which means that all documents matching the
// filter will be returned. A negative limit specifies that the resulting documents should be returned in a single
// batch. The default value is 0.
Limit *int64