Question

[
   { "item": "journal", "qty": 25,"date":"1/1/2016", "status": "A" },
   { "item": "notebook", "qty": 50,"date":"10/1/2016", "status": "A" },
   { "item": "paper", "qty": 100,"date":"20/1/2016", "status": "D" },
   { "item": "planner", "qty": 75,"date":"1/2/2016", "status": "D" },
   { "item": "postcard", "qty": 45,"date":"10/2/2016", "status": "A" },
   { "item": "postcard", "qty": 45,"date":"20/5/2016", "status": "A" },
   { "item": "postcard", "qty": 45,"date":"30/7/2016", "status": "A" },
   { "item": "postcard", "qty": 45,"date":"2/3/2017", "status": "A" },
   { "item": "postcard", "qty": 45,"date":"5/5/2017", "status": "A" },
   { "item": "postcard", "qty": 45,"date":"6/5/2017", "status": "A" },
   { "item": "postcard", "qty": 45,"date":"8/10/2017", "status": "A" },
   { "item": "postcard", "qty": 45,"date":"11/10/2017", "status": "A" },
   { "item": "postcard", "qty": 45,"date":"12/11/2017", "status": "A" },
   { "item": "postcard", "qty": 45,"date":"4/3/2018", "status": "A" },
   { "item": "postcard", "qty": 45,"date":"5/6/2018", "status": "A" },
   { "item": "postcard", "qty": 45,"date":"6/7/2018", "status": "A" },
   { "item": "postcard", "qty": 45,"date":"7/7/2018", "status": "A" },
   { "item": "postcard", "qty": 45,"date":"17/11/2018", "status": "A" },
   { "item": "postcard", "qty": 45,"date":"19/12/2018", "status": "A" },
   { "item": "postcard", "qty": 45,"date":"5/1/2019", "status": "A" },
   { "item": "postcard", "qty": 45,"date":"7/1/2019", "status": "A" },
   { "item": "postcard", "qty": 45,"date":"14/3/2019", "status": "A" }
]

以上是我的数据库结构。

db.lichi.find({date: {$gte : '1/1/2016', $lt : '1/1/2019'}})

这是我要从数据库中获取数据的查询。

在数据库中，我有字符串格式的日期。我正试图以上述方式获取信息，但没有用。

给出结果

  { "item": "journal", "qty": 25,"date":"1/1/2016", "status": "A" },
  { "item": "notebook", "qty": 50,"date":"10/1/2016", "status": "A" }

只有两个文档。

请看看。

Answer 1

将日期存储为字符串不是最好的方法，因为在这种情况下，您必须比较字符串而不是日期。如果由于某种原因必须将date保留为字符串，则可以使用$dateFromString在查询中将其转换，然后应用过滤条件：

db.lichi.aggregate([
    {
        $addFields: {
            date: {
                $dateFromString: {
                    dateString: "$date",
                    format: "%d/%m/%Y"
                }
            }
        }
    },
    {
        $match: {
            date: { $gte: ISODate("2016-01-01T00:00:00Z"), $lt: ISODate("2019-01-01T00:00:00Z") }
        }
    }
])

如何从mongodb到字符串格式的日期之间过滤数据库

1 个答案: