我经过实际测试es5.2.2，发现_source/_all特性很好用：
1. _source可用通过配置includes、excludes获取应用需要的field
"_source": {
          "enabled": true,
          "includes": [
            "comId",
            "name",
            "userName",
            "equips.name",
            "equips.amount"
          ],
          "excludes": [
            "phone",
            "equips.code"
          ]
        },
2.设置enabled=false关闭_source功能，关闭后，查询结果只返回doc的ID，而不会返回_source
 "_source": {
          "enabled": false,
3._all、include_in_all结合使用，是用户可用通过_all分词查询多个字段，而不需要写多个查询条件
 "mappings": {
      "testdoc03": {
        "_all": {
          "enabled": true
        },
        "_source": {
          "enabled": false,
          "includes": [
            "comId",
            "name",
            "userName",
            "equips.name",
            "equips.amount"
          ],
          "excludes": [
            "phone",
            "equips.code"
          ]
        },
        "properties": {
          "comId": {
            "type": "long"
          },
          "equips": {
            "properties": {
              "amount": {
                "type": "double",
                "include_in_all": true
              },
              "code": {
                "type": "text"
              },
              "name": {
                "type": "text",
                "include_in_all": true
              }
            }
          },
          "name": {
            "type": "text",
            "include_in_all": true
          },
          "phone": {
            "type": "keyword"
          },
          "userName": {
            "type": "text",
            "include_in_all": true
          }
        }
      }
    }
  }