【问题】

Trying to find the dataList rows that have the first element in the string array greater than 6154 and less than or equal to 6155.  Is it possible using MongoDB. For example I am expecting mongoDB to return the rows:        “6154.5,37.9,1.529,1.429,1.429”,
            “6155,30.4,1.505,1.532,1.543”,

 Collection which has the following structure:

{
        “_id” : ObjectId(“54f6a766bf4436333edcd6a2”),
        “_class” : “com.abc.core.bo.obj.Objs”,
        “objList” : [
                {
                        “name” : “ABB-09”,
                        “uid” : “ABB-09”,
                        “data” : {
                                “dataId” : NumberLong(0),
                                “dataList” : [
            “6150,32.9,1.475,,1.434”,
            “6150.5,43,,1.529,1.402”,
            “6151,31.8,1.506,1.447,1.453”,
            “6151.5,33.6,1.481,1.456,1.521”,
            “6152,30.9,1.465,1.472,1.547”,
            “6152.5,39.5,1.404,1.425,1.485”,
            “6153,43.2,1.406,1.446,1.481”,
            “6153.5,39.5,1.433,1.468,1.488”,
            “6154,32.7,1.459,1.477,1.427”,
            “6154.5,37.9,1.529,1.429,1.429”,
            “6155,30.4,1.505,1.532,1.543”,
            “6155.5,37.3,1.49,1.436,1.462”,
            “6156,35.3,1.538,1.45,1.488”,
            “6156.5,37.3,1.517,1.535,1.473”,
            “6157,32.7,1.401,1.405,1.497”,
            “6157.5,38.9,1.488,1.468,1.499”,
            “6158,35.4,1.526,1.422,1.452”,
            “6158.5,43.3,1.516,1.433,1.491”,
            “6159,34.6,1.519,1.442,1.478”,
            “6159.5,42.7,1.426,1.514,1.428”,
      “6160,32.7,1.451,1.5,1.516”
            ]
           }
          }] }

【回答】

问题是，要将 mongodb 中的一系列字符串记录按照逗号分割的首个数字值筛选。直接使用 Mongodb 的 API 应该可以实现这个需求，但会比较繁琐，可以考虑用 SPL 解决：

A3：找到需要计算的数据序列

A4：将每个字符串成员转成序列，取第一个子成员，根据其选择数据