【绝对无坑】Mongodb获取集合的字段以及数据类型信息

Mongodb获取集合的字段以及数据类型信息

感觉很LOW的一个数据仓工具seatunel，竟然不能自动读取mongodb的表结构信息，需要手工创建。
然鹅，本人对mongodb也是新手，很多操作也不知所措，作为一个DBA，始终还是被研发的甩锅，没得办法只能想办法帮忙把集合的字段类型导出来给他。

网上找了很多方法都不行，坑太多了。

原本想使用mongodump工具导出，但是由于版本限制，mongodb4.4版本才支持schemaonly参数，本人服务器的版本是4.2

在此，为了方便需要的小伙伴，就此贴出无坑版操作代码，希望有所帮助：

winrs:PRIMARY> use testdb;
switched to db testdb
winrs:PRIMARY> var collection = db.dbaList;
winrs:PRIMARY> var fields = {};
winrs:PRIMARY> collection.find().forEach(function(doc) {
...     for (var key in doc) {
...         if (!fields[key]) {
...             fields[key] = typeof doc[key];
...         }
...     }
... });
winrs:PRIMARY> printjson(fields);
{
        "_id" : "number",
        "n" : "string",
        "brand" : "string",
        "stand" : "string",
        "group" : "string",
        "area" : "string",
        "dept" : "string",
        "ip" : "string",
        "port" : "number",
        "sta" : "number",
        "c_sta" : "number",
        "e_flag" : "number",
        "u_t" : "string",
        "w_t" : "string",
        "sta_t" : "string",
        "c_sta_t" : "string",
        "stop_t" : "string",
        "power" : "number",
        "v" : "number",
        "s" : "number",
        "h" : "number",
        "b_a" : "number",
        "w_a" : "number",
        "h_a" : "number",
        "l" : "number",
        "e_c" : "object",
        "m_c" : "object",
        "o_c" : "object",
        "timer" : "number",
        "count" : "number",
        "e_send" : "number",
        "m_sta" : "number",
        "s_sta" : "number",
        "sta_his_id" : "string",
        "alert_his_id" : "object",
        "c_sta_his_id" : "string",
        "alert_time" : "object",
        "ensure" : "number",
        "update_time" : "string",
        "fmis_id" : "string",
        "remarks" : "string",
        "ensure_time" : "string",
        "user_id" : "string"
}