index: { "uid" : -1, "infor.orderStatus" : 1, "exts.post_his.unpostids" : 1, "infor.gmtModified" : -1, "exts.dvy_sign.issigned" : 1, "infor.issueInfo.issueStatus" : 1 } when I run the finding code: db.getCollection('w_trade_aliexpress').find({ "uid" : 3630, "infor.gmtModified" : { "$gt" : ISODate("2016-02-03T00:30:08.000+08:00"), "$lt" : ISODate("2016-03-06T15:56:07.670+08:00") }, "exts.post_his.unpostids" : "56c5666bef68fc0e28524dd5", "exts.dvy_sign.issigned" : true, "infor.orderStatus" : "FINISH" }).explain() the explain: /* 1 */ { "queryPlanner" : { "plannerVersion" : 1, "namespace" : "wxwdb.w_trade_aliexpress", "indexFilterSet" : false, "parsedQuery" : { "$and" : [ { "exts.dvy_sign.issigned" : { "$eq" : true } }, { "exts.post_his.unpostids" : { "$eq" : "56c5666bef68fc0e28524dd5" } }, { "infor.orderStatus" : { "$eq" : "FINISH" } }, { "uid" : { "$eq" : 3630 } }, { "infor.gmtModified" : { "$lt" : ISODate("2016-03-06T15:56:07.670+08:00") } }, { "infor.gmtModified" : { "$gt" : ISODate("2016-02-03T00:30:08.000+08:00") } } ] }, "winningPlan" : { "stage" : "FETCH", "filter" : { "$and" : [ { "exts.post_his.unpostids" : { "$eq" : "56c5666bef68fc0e28524dd5" } }, { "infor.gmtModified" : { "$lt" : ISODate("2016-03-06T15:56:07.670+08:00") } }, { "infor.gmtModified" : { "$gt" : ISODate("2016-02-03T00:30:08.000+08:00") } } ] }, "inputStage" : { "stage" : "IXSCAN", "keyPattern" : { "uid" : -1, "infor.orderStatus" : 1, "exts.post_his.unpostids" : 1, "infor.gmtModified" : -1, "exts.dvy_sign.issigned" : 1, "infor.issueInfo.issueStatus" : 1 }, "indexName" : "posting2", "isMultiKey" : true, "isUnique" : false, "isSparse" : false, "isPartial" : false, "indexVersion" : 1, "direction" : "forward", "indexBounds" : { "uid" : [ "[3630.0, 3630.0]" ], "infor.orderStatus" : [ "[\"FINISH\", \"FINISH\"]" ], "exts.post_his.unpostids" : [ "[MinKey, MaxKey]" ], "infor.gmtModified" : [ "[MaxKey, MinKey]" ], "exts.dvy_sign.issigned" : [ "[true, true]" ], "infor.issueInfo.issueStatus" : [ "[MinKey, MaxKey]" ] } } }, "rejectedPlans" : [ { "stage" : "FETCH", "filter" : { "$and" : [ { "exts.dvy_sign.issigned" : { "$eq" : true } }, { "exts.post_his.unpostids" : { "$eq" : "56c5666bef68fc0e28524dd5" } }, { "infor.orderStatus" : { "$eq" : "FINISH" } }, { "infor.gmtModified" : { "$lt" : ISODate("2016-03-06T15:56:07.670+08:00") } }, { "infor.gmtModified" : { "$gt" : ISODate("2016-02-03T00:30:08.000+08:00") } } ] }, "inputStage" : { "stage" : "IXSCAN", "keyPattern" : { "uid" : -1, "infor.id" : -1 }, "indexName" : "uid_-1_infor.id_-1", "isMultiKey" : false, "isUnique" : false, "isSparse" : false, "isPartial" : false, "indexVersion" : 1, "direction" : "forward", "indexBounds" : { "uid" : [ "[3630.0, 3630.0]" ], "infor.id" : [ "[MaxKey, MinKey]" ] } } }, { "stage" : "FETCH", "filter" : { "$and" : [ { "exts.dvy_sign.issigned" : { "$eq" : true } }, { "exts.post_his.unpostids" : { "$eq" : "56c5666bef68fc0e28524dd5" } }, { "infor.orderStatus" : { "$eq" : "FINISH" } }, { "infor.gmtModified" : { "$lt" : ISODate("2016-03-06T15:56:07.670+08:00") } }, { "infor.gmtModified" : { "$gt" : ISODate("2016-02-03T00:30:08.000+08:00") } } ] }, "inputStage" : { "stage" : "IXSCAN", "keyPattern" : { "uid" : 1, "exts.eval.evaluatetime" : -1 }, "indexName" : "uid_1_exts.eval.evaluatetime_-1", "isMultiKey" : false, "isUnique" : false, "isSparse" : false, "isPartial" : false, "indexVersion" : 1, "direction" : "forward", "indexBounds" : { "uid" : [ "[3630.0, 3630.0]" ], "exts.eval.evaluatetime" : [ "[MaxKey, MinKey]" ] } } } ] }, "serverInfo" : { "host" : "jstw4vbjuh7q7c", "port" : 3005, "version" : "3.2.3", "gitVersion" : "b326ba837cf6f49d65c2f85e1b70f6f31ece7937" }, "ok" : 1 }