func (qw *QueryWork) Do(c chan<- interface{}) {
customerID := qw.randSource.Int31n(MaxNumCustomers)
cashRegisterID := qw.randSource.Int31n(MaxNumCashRegisters)
price := qw.randSource.Float64()*MaxPrice + float64(customerID)/100.0
// generate a random time since qw.StartTime
// there is likely a better way to do this
since := time.Since(qw.startTime)
sinceInNano := since.Nanoseconds()
var randomTime int64
if sinceInNano > 0 {
randomTime = qw.randSource.Int63n(sinceInNano)
}
timeToQuery := qw.startTime.Add(time.Duration(randomTime))
var query *mgo.Query
if qw.numQueriesSoFar%3 == 0 {
filter := bson.M{"$or": []bson.M{
bson.M{"pr": price, "ts": timeToQuery, "cid": bson.M{"$gte": customerID}},
bson.M{"pr": price, "ts": bson.M{"$gt": timeToQuery}},
bson.M{"pr": bson.M{"$gt": price}}}}
projection := bson.M{"pr": 1, "ts": 1, "cid": 1}
query = qw.coll.Find(filter).Select(projection).Hint("pr", "ts", "cid")
} else if qw.numQueriesSoFar%3 == 1 {
filter := bson.M{"$or": []bson.M{
bson.M{"crid": cashRegisterID, "pr": price, "cid": bson.M{"$gte": customerID}},
bson.M{"crid": cashRegisterID, "pr": bson.M{"$gt": price}},
bson.M{"crid": bson.M{"$gt": cashRegisterID}}}}
projection := bson.M{"crid": 1, "pr": 1, "cid": 1}
query = qw.coll.Find(filter).Select(projection).Hint("crid", "pr", "cid")
} else {
filter := bson.M{"$or": []bson.M{
bson.M{"pr": price, "cid": bson.M{"$gte": customerID}},
bson.M{"pr": bson.M{"$gt": price}}}}
projection := bson.M{"pr": 1, "cid": 1}
query = qw.coll.Find(filter).Select(projection).Hint("pr", "cid")
}
var result bson.M
iter := query.Limit(*queryResultLimit).Iter()
for iter.Next(&result) {
}
qw.numQueriesSoFar++
c <- Result{NumQueries: 1}
}
