RethinkDB上两个带有OR条件的过滤器

Question

I've a struct :

type Talk struct {
    Id string `gorethink:"id,omitempty"`
    MatchId string
    UserIdX string
    UserIdY string
    UserNameX string
    UserNameY string
    CreatedAt time.Time
}

My current Talk struct looks like this:

{
    "CreatedAt": Wed Sep 14 2016 21:36:26 GMT+02:00 ,
    "MatchId":  "172d51fa-438b-49a5-bbe5-422377f09336" ,
    "UserIdX":  "acc4e0b6-d33b-4755-9c0a-ae5309c2ba75" ,
    "UserIdY":  "03f76d8b-ed6a-4c0f-9cde-27b17c9e7cdb" ,
    "UserNameX":  "Barbara" ,
    "UserNameY":  "Louis" ,
    "id":  "ead3f1b0-b242-4c6d-8027-a59572b58649"
}

How can I retrieve a talk, with a single query, where:

(UserIdX == talk.UserIdX AND UserIdY == talk.UserIdY) OR (UserIdX == talk.UserIdY AND UserIdY == talk.UserIdX)

I actually do it like the following:

func (talk *Talk) GetTalkByUsersId() bool {
    talk1 := new(Talk)
    talk2 := new(Talk)

    curs, _ :=  r.Table("Talks").
                Filter(r.Row.Field("UserIdX").Eq(talk.UserIdX)).
                Filter(r.Row.Field("UserIdY").Eq(talk.UserIdY)).
                Run(api.Sess)

    curs2, _ :=  r.Table("Talks").
                Filter(r.Row.Field("UserIdX").Eq(talk.UserIdY)).
                Filter(r.Row.Field("UserIdY").Eq(talk.UserIdX)).
                Run(api.Sess)

    curs.One(&talk1)
    curs2.One(&talk2)
    if talk1.Id == "" && talk2.Id == "" {
        return false
    }
    if talk1.Id != "" {
        talk.copyTalk(talk1)
    } else {
        talk.copyTalk(talk2)
    }
    return true
}

How can I get this to work in a much simpler way?

Answer 1

I'm going to summon @daniel-cannon here but I think this is what you're looking for and will vastly simplify this query and reduce it to just a single query. But just two tips:

• r.And and r.Or and their two use cases are very much your friends for doing some tricky logical conditions.
  • https://www.rethinkdb.com/api/javascript/#and
  • https://www.rethinkdb.com/api/javascript/#or
• You can provide anonymous functions to .Filter to do things that would be kind of ugly with the simplified r.Row pattern.

r.Table("talks").Filter(func(talk r.Term) r.Term {
    return r.Or(
        r.And(talk.Field("UserIdX").Eq(UserIdX), talk.Field("UserIdX").Eq(UserIdY)),
        r.And(talk.Field("UserIdY").Eq(UserIdX), talk.Field("UserIdX").Eq(UserIdY)),
    )
}).Run(api.Sess)

I hope this helps!