2011-09-07 13 views
4

私は奇妙なMapReduceの問題があります。MapReduceの問題

地図機能:

> mp 
function() { 
    emit(this.ContractID, {qty:this.Qty, qtybs:this.QtyBs}); 
} 

7つの契約の機能

> red 
function (key, values) { 
    var sum1 = 0, sum2 = 0; 
    values.forEach(function (doc) {sum1 += doc.qty;sum2 += doc.qtybs;}); 
    return {a:sum1, b:sum2}; 
} 

実行MRの削減:

> result = db.fact_payments.mapReduce(mp, red, {out:"myout2", query:{ContractID:{$lte:10000100042}}}); 
{ 
     "result" : "myout2", 
     "timeMillis" : 670, 
     "counts" : { 
       "input" : 591, 
       "emit" : 591, 
       "output" : 7 
     }, 
     "ok" : 1, 
} 
> db.myout2.find() 
{ "_id" : NumberLong("10000000042"), "value" : { "a" : 8331.04, "b" : 253835.07999999996 } } 
{ "_id" : NumberLong("10000000084"), "value" : { "a" : 4728.480000000001, "b" : 142879.88000000003 } } 
{ "_id" : NumberLong("10000000129"), "value" : { "a" : 25421.859999999997, "b" : 756036.9499999998 } } 
{ "_id" : NumberLong("10000000140"), "value" : { "a" : 477292.0000000002, "b" : 477292.0000000002 } } 
{ "_id" : NumberLong("10000000148"), "value" : { "a" : 7912.0599999999995, "b" : 237926.87999999998 } } 
{ "_id" : NumberLong("10000000165"), "value" : { "a" : 35391.31999999999, "b" : 1074180.95 } } 
{ "_id" : NumberLong("10000000171"), "value" : { "a" : 62189.52, "b" : 62189.52 } } 
> 

それは大丈夫ですすべての、すべての契約は、結果を持っている:)

すべての契約でMRを実行するS:

異なる結果との契約のidの同じ
> result = db.fact_payments.mapReduce(mp, red, {out:"myout2", query:{ContractID:{$lte:100100000042}}}); 
{ 
     "result" : "myout2", 
     "timeMillis" : 26273, 
     "counts" : { 
       "input" : 295765, 
       "emit" : 295765, 
       "output" : 7793 
     }, 
     "ok" : 1, 
} 
> db.myout2.find() 
{ "_id" : NumberLong("10000000042"), "value" : { "a" : NaN, "b" : NaN } } 
{ "_id" : NumberLong("10000000084"), "value" : { "a" : 4728.480000000001, "b" : 142879.88000000003 } } 
{ "_id" : NumberLong("10000000129"), "value" : { "a" : NaN, "b" : NaN } } 
{ "_id" : NumberLong("10000000140"), "value" : { "a" : NaN, "b" : NaN } } 
{ "_id" : NumberLong("10000000148"), "value" : { "a" : NaN, "b" : NaN } } 
{ "_id" : NumberLong("10000000165"), "value" : { "a" : NaN, "b" : NaN } } 
{ "_id" : NumberLong("10000000171"), "value" : { "a" : 62189.52, "b" : 62189.52 } } 
{ "_id" : NumberLong("10005000172"), "value" : { "a" : NaN, "b" : NaN } } 
{ "_id" : NumberLong("10005000173"), "value" : { "a" : NaN, "b" : NaN } } 
{ "_id" : NumberLong("10005000189"), "value" : { "a" : NaN, "b" : NaN } } 
{ "_id" : NumberLong("10005000191"), "value" : { "a" : 8261.759999999998, "b" : 253916.7 } } 
{ "_id" : NumberLong("10005000199"), "value" : { "a" : NaN, "b" : NaN } } 
{ "_id" : NumberLong("10005000206"), "value" : { "a" : NaN, "b" : NaN } } 
{ "_id" : NumberLong("10005000213"), "value" : { "a" : NaN, "b" : NaN } } 
{ "_id" : NumberLong("10010000200"), "value" : { "a" : NaN, "b" : NaN } } 
{ "_id" : NumberLong("10010000224"), "value" : { "a" : NaN, "b" : NaN } } 
{ "_id" : NumberLong("10010000229"), "value" : { "a" : NaN, "b" : NaN } } 
{ "_id" : NumberLong("10010000240"), "value" : { "a" : 32843.32, "b" : 32843.32 } } 
{ "_id" : NumberLong("10010000243"), "value" : { "a" : NaN, "b" : NaN } } 
{ "_id" : NumberLong("10010000244"), "value" : { "a" : NaN, "b" : NaN } } 
has more 

:私はすべての任意のアイデアを持っていない

{ "_id" : NumberLong("10000000042"), "value" : { "a" : 8331.04, "b" : 253835.07999999996 } } 

{ "_id" : NumberLong("10000000042"), "value" : { "a" : NaN, "b" : NaN } } 

答えて

11

あなたはそれが動作するはずです、次への最後の行を変更した場合:

return {qty:sum1, qtybs:sum2}; 

をルール(reduce関数の戻り値が発光する第二引数と同じ「形」をしなければならないことをしていますreduceの出力がreduce関数にフィードバックされるので、reduceの入力です)。詳細については、http://www.mongodb.org/display/DOCS/MapReduce#MapReduce-ReduceFunctionを参照してください。

+0

うわー、ありがとう。私はこのルールを逃した。 – Igorekk