MongoDB保留满足条件的路径

我是MongoDB的新手

在查找查询中，我使用以下结构：

db.report.find({'accountList.transactionList.description': /.*aear.*/i})

但是，accountList包含多个值，transaction list也包含多个值，确切的查询是：

db.report.find({'accountList[0].transactionList[4].description': /.*aear.*/i})

问题是accountList有多个帐户，其中只有一个在描述中具有值“aear”。当我执行查询时，它会返回两个帐户，我只想保留描述中aear所在的帐户。此外，这必须适用于许多文件，因为它的文件具有不同的事务列表，因此在某些文档中，aear根本不会出现，而在其他文档中，它可能会出现多种类型，始终处于不同的位置。我认为必须在投影中做一些事情，但这样设置是不起作用的：

.projection({"accountList.id":1,"accountList.transactionList.description":1})

以下是输出：

"accountList" : [
        {
            "id" : "1",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : [
                {
                    "onDate" : ISODate("2019-08-25T21:00:00.000-03:00"),
                    "description" : "aear"
                },
                {
                    "onDate" : ISODate("2019-08-25T21:00:00.000-03:00"),
                    "description" : "bb"
                },
                {
                    "onDate" : ISODate("2019-08-25T21:00:00.000-03:00"),
                    "description" : "cc"
                }
            ]
        },
        {
            "id" : "2",
            "type" : "xD",
            "currency" : "USD",
            "transactionList" : [
                {
                    "onDate" : ISODate("2019-08-15T21:00:00.000-03:00"),
                    "description" : "aa",
                },
                {
                    "onDate" : ISODate("2019-08-14T21:00:00.000-03:00"),
                    "description" : "ee"
                }
            ]
        }
    ]

我想要这样的东西，我只得到满足条件的路径：

"accountList" : [
        {
            "id" : "1",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : [
                {
                    "onDate" : ISODate("2019-08-25T21:00:00.000-03:00"),
                    "description" : "aear"
                },

请尝试以下查询：

db.report.find({'accountList[0].transactionList[4].description': { $regex: /.*aear.*/i} })

或-仅返回第一个匹配的文档：

db.report.find({'accountList[0].transactionList[4].description': /.*aear.*/i}).limit(1)

---

更新我的答案，因为此问题已更新为新的所需o/p：

新问题的答案：

    /* 1 */
{
    "accountList" : [ 
        {
            "id" : "1100",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : {
                "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                "description" : "aear"
            }
        }, 
        {
            "id" : "1200",
            "type" : "xD",
            "currency" : "USD",
            "transactionList" : {
                "onDate" : ISODate("2019-08-16T00:00:00.000Z"),
                "description" : "aear"
            }
        }
    ]
}

/* 2 */
{
    "accountList" : [ 
        {
            "id" : "1",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : {
                "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                "description" : "aear"
            }
        }
    ]
}

/* 1 */
{
    "accountList" : [ 
        {
            "id" : "1100",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : [ 
                {
                    "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                    "description" : "aear"
                }
            ]
        }, 
        {
            "id" : "1200",
            "type" : "xD",
            "currency" : "USD",
            "transactionList" : [ 
                {
                    "onDate" : ISODate("2019-08-16T00:00:00.000Z"),
                    "description" : "aear"
                }
            ]
        }
    ]
}

/* 2 */
{
    "accountList" : [ 
        {
            "id" : "1",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : [ 
                {
                    "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                    "description" : "aear"
                }
            ]
        }
    ]
}

/* 3 */
{
    "accountList" : [ 
        {
            "id" : "00",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : [ 
                {
                    "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                    "description" : "aear"
                }, 
                {
                    "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                    "description" : "aear"
                }
            ]
        }, 
        {
            "id" : "100",
            "type" : "xD",
            "currency" : "USD",
            "transactionList" : [ 
                {
                    "onDate" : ISODate("2019-08-16T00:00:00.000Z"),
                    "description" : "aear"
                }
            ]
        }
    ]
}

/* 1 */
{
    "_id" : ObjectId("5d6435145a0d22d3c86df0c7"),
    "accountList" : [ 
        {
            "id" : "4474",
            "transactionList" : [ 
                {
                    "description" : "aear"
                }, 
                {
                    "description" : "koe"
                }
            ]
        }
    ]
}

/* 2 */
{
    "_id" : ObjectId("5d6435145a0d22d3c86df0d7"),
    "accountList" : [ 
        {
            "id" : "4400",
            "transactionList" : [ 
                {
                    "description" : "aear"
                }, 
                {
                    "description" : "koe"
                }
            ]
        }
    ]
}

/* 3 */
{
    "_id" : ObjectId("5d6435145a0d22d3c86df077"),
    "accountList" : [ 
        {
            "id" : "0000",
            "transactionList" : [ 
                {
                    "description" : "aear"
                }, 
                {
                    "description" : "koe"
                }
            ]
        }
    ]
}

/* 4 */
{
    "_id" : ObjectId("5d6435145a0d22d3c86df1c7"),
    "accountList" : [ 
        {
            "id" : "0101",
            "transactionList" : [ 
                {
                    "description" : "aear"
                }, 
                {
                    "description" : "koe"
                }
            ]
        }
    ]
}

如果您只有一个交易符合给定的标准

/.*aear.*/i

，那么假设描述在报告文档的会计列表数组中是唯一的（与提供的示例完全相同）：

但是，如果您有多个描述（跨报表文档accountsList数组中的多个对象）与accountList中的给定条件匹配：

db.report.aggregate([{
    $match: {
        'accountList.transactionList.description': /.*aear.*/i
    }
}, { $unwind: '$accountList' }, { $unwind: '$accountList.transactionList' }, { $match: { 'accountList.transactionList.description': /.*aear.*/i } },
{ $group: { _id: '$_id', accountList: { $push: '$accountList' }, data: { $first: '$$ROOT' } } }
    , { $addFields: { 'data.accountList': '$accountList' } }, { $replaceRoot: { 'newRoot': '$data' } }, { $project: { 'accountList': 1, _id: 0 } }
])

输出：

    /* 1 */
{
    "accountList" : [ 
        {
            "id" : "1100",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : {
                "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                "description" : "aear"
            }
        }, 
        {
            "id" : "1200",
            "type" : "xD",
            "currency" : "USD",
            "transactionList" : {
                "onDate" : ISODate("2019-08-16T00:00:00.000Z"),
                "description" : "aear"
            }
        }
    ]
}

/* 2 */
{
    "accountList" : [ 
        {
            "id" : "1",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : {
                "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                "description" : "aear"
            }
        }
    ]
}

/* 1 */
{
    "accountList" : [ 
        {
            "id" : "1100",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : [ 
                {
                    "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                    "description" : "aear"
                }
            ]
        }, 
        {
            "id" : "1200",
            "type" : "xD",
            "currency" : "USD",
            "transactionList" : [ 
                {
                    "onDate" : ISODate("2019-08-16T00:00:00.000Z"),
                    "description" : "aear"
                }
            ]
        }
    ]
}

/* 2 */
{
    "accountList" : [ 
        {
            "id" : "1",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : [ 
                {
                    "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                    "description" : "aear"
                }
            ]
        }
    ]
}

/* 3 */
{
    "accountList" : [ 
        {
            "id" : "00",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : [ 
                {
                    "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                    "description" : "aear"
                }, 
                {
                    "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                    "description" : "aear"
                }
            ]
        }, 
        {
            "id" : "100",
            "type" : "xD",
            "currency" : "USD",
            "transactionList" : [ 
                {
                    "onDate" : ISODate("2019-08-16T00:00:00.000Z"),
                    "description" : "aear"
                }
            ]
        }
    ]
}

/* 1 */
{
    "_id" : ObjectId("5d6435145a0d22d3c86df0c7"),
    "accountList" : [ 
        {
            "id" : "4474",
            "transactionList" : [ 
                {
                    "description" : "aear"
                }, 
                {
                    "description" : "koe"
                }
            ]
        }
    ]
}

/* 2 */
{
    "_id" : ObjectId("5d6435145a0d22d3c86df0d7"),
    "accountList" : [ 
        {
            "id" : "4400",
            "transactionList" : [ 
                {
                    "description" : "aear"
                }, 
                {
                    "description" : "koe"
                }
            ]
        }
    ]
}

/* 3 */
{
    "_id" : ObjectId("5d6435145a0d22d3c86df077"),
    "accountList" : [ 
        {
            "id" : "0000",
            "transactionList" : [ 
                {
                    "description" : "aear"
                }, 
                {
                    "description" : "koe"
                }
            ]
        }
    ]
}

/* 4 */
{
    "_id" : ObjectId("5d6435145a0d22d3c86df1c7"),
    "accountList" : [ 
        {
            "id" : "0101",
            "transactionList" : [ 
                {
                    "description" : "aear"
                }, 
                {
                    "description" : "koe"
                }
            ]
        }
    ]
}

如果您在事务数组和帐户的其他对象数组中有多个匹配描述（这也适用于上述所有场景，但根据需求可能不需要，它可能会很庞大，请检查输出中的文档#3以了解详情）：

输出：

    /* 1 */
{
    "accountList" : [ 
        {
            "id" : "1100",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : {
                "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                "description" : "aear"
            }
        }, 
        {
            "id" : "1200",
            "type" : "xD",
            "currency" : "USD",
            "transactionList" : {
                "onDate" : ISODate("2019-08-16T00:00:00.000Z"),
                "description" : "aear"
            }
        }
    ]
}

/* 2 */
{
    "accountList" : [ 
        {
            "id" : "1",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : {
                "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                "description" : "aear"
            }
        }
    ]
}

/* 1 */
{
    "accountList" : [ 
        {
            "id" : "1100",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : [ 
                {
                    "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                    "description" : "aear"
                }
            ]
        }, 
        {
            "id" : "1200",
            "type" : "xD",
            "currency" : "USD",
            "transactionList" : [ 
                {
                    "onDate" : ISODate("2019-08-16T00:00:00.000Z"),
                    "description" : "aear"
                }
            ]
        }
    ]
}

/* 2 */
{
    "accountList" : [ 
        {
            "id" : "1",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : [ 
                {
                    "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                    "description" : "aear"
                }
            ]
        }
    ]
}

/* 3 */
{
    "accountList" : [ 
        {
            "id" : "00",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : [ 
                {
                    "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                    "description" : "aear"
                }, 
                {
                    "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                    "description" : "aear"
                }
            ]
        }, 
        {
            "id" : "100",
            "type" : "xD",
            "currency" : "USD",
            "transactionList" : [ 
                {
                    "onDate" : ISODate("2019-08-16T00:00:00.000Z"),
                    "description" : "aear"
                }
            ]
        }
    ]
}

/* 1 */
{
    "_id" : ObjectId("5d6435145a0d22d3c86df0c7"),
    "accountList" : [ 
        {
            "id" : "4474",
            "transactionList" : [ 
                {
                    "description" : "aear"
                }, 
                {
                    "description" : "koe"
                }
            ]
        }
    ]
}

/* 2 */
{
    "_id" : ObjectId("5d6435145a0d22d3c86df0d7"),
    "accountList" : [ 
        {
            "id" : "4400",
            "transactionList" : [ 
                {
                    "description" : "aear"
                }, 
                {
                    "description" : "koe"
                }
            ]
        }
    ]
}

/* 3 */
{
    "_id" : ObjectId("5d6435145a0d22d3c86df077"),
    "accountList" : [ 
        {
            "id" : "0000",
            "transactionList" : [ 
                {
                    "description" : "aear"
                }, 
                {
                    "description" : "koe"
                }
            ]
        }
    ]
}

/* 4 */
{
    "_id" : ObjectId("5d6435145a0d22d3c86df1c7"),
    "accountList" : [ 
        {
            "id" : "0101",
            "transactionList" : [ 
                {
                    "description" : "aear"
                }, 
                {
                    "description" : "koe"
                }
            ]
        }
    ]
}

如果要查找精确文本，也可以这样做（因为cond中不允许使用正则表达式）：

输出：同上

回答老问题：

    /* 1 */
{
    "accountList" : [ 
        {
            "id" : "1100",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : {
                "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                "description" : "aear"
            }
        }, 
        {
            "id" : "1200",
            "type" : "xD",
            "currency" : "USD",
            "transactionList" : {
                "onDate" : ISODate("2019-08-16T00:00:00.000Z"),
                "description" : "aear"
            }
        }
    ]
}

/* 2 */
{
    "accountList" : [ 
        {
            "id" : "1",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : {
                "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                "description" : "aear"
            }
        }
    ]
}

/* 1 */
{
    "accountList" : [ 
        {
            "id" : "1100",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : [ 
                {
                    "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                    "description" : "aear"
                }
            ]
        }, 
        {
            "id" : "1200",
            "type" : "xD",
            "currency" : "USD",
            "transactionList" : [ 
                {
                    "onDate" : ISODate("2019-08-16T00:00:00.000Z"),
                    "description" : "aear"
                }
            ]
        }
    ]
}

/* 2 */
{
    "accountList" : [ 
        {
            "id" : "1",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : [ 
                {
                    "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                    "description" : "aear"
                }
            ]
        }
    ]
}

/* 3 */
{
    "accountList" : [ 
        {
            "id" : "00",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : [ 
                {
                    "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                    "description" : "aear"
                }, 
                {
                    "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                    "description" : "aear"
                }
            ]
        }, 
        {
            "id" : "100",
            "type" : "xD",
            "currency" : "USD",
            "transactionList" : [ 
                {
                    "onDate" : ISODate("2019-08-16T00:00:00.000Z"),
                    "description" : "aear"
                }
            ]
        }
    ]
}

/* 1 */
{
    "_id" : ObjectId("5d6435145a0d22d3c86df0c7"),
    "accountList" : [ 
        {
            "id" : "4474",
            "transactionList" : [ 
                {
                    "description" : "aear"
                }, 
                {
                    "description" : "koe"
                }
            ]
        }
    ]
}

/* 2 */
{
    "_id" : ObjectId("5d6435145a0d22d3c86df0d7"),
    "accountList" : [ 
        {
            "id" : "4400",
            "transactionList" : [ 
                {
                    "description" : "aear"
                }, 
                {
                    "description" : "koe"
                }
            ]
        }
    ]
}

/* 3 */
{
    "_id" : ObjectId("5d6435145a0d22d3c86df077"),
    "accountList" : [ 
        {
            "id" : "0000",
            "transactionList" : [ 
                {
                    "description" : "aear"
                }, 
                {
                    "description" : "koe"
                }
            ]
        }
    ]
}

/* 4 */
{
    "_id" : ObjectId("5d6435145a0d22d3c86df1c7"),
    "accountList" : [ 
        {
            "id" : "0101",
            "transactionList" : [ 
                {
                    "description" : "aear"
                }, 
                {
                    "description" : "koe"
                }
            ]
        }
    ]
}

好的，这里有两个选项，请尝试以下选项：

如果

accountList

中只有一个对象与给定的过滤器匹配，则可以简单地执行以下操作：

db.report.find({'accountList.transactionList.description': /.*aear.*/i}, {'accountList.$': 1})

输出：

    /* 1 */
{
    "accountList" : [ 
        {
            "id" : "1100",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : {
                "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                "description" : "aear"
            }
        }, 
        {
            "id" : "1200",
            "type" : "xD",
            "currency" : "USD",
            "transactionList" : {
                "onDate" : ISODate("2019-08-16T00:00:00.000Z"),
                "description" : "aear"
            }
        }
    ]
}

/* 2 */
{
    "accountList" : [ 
        {
            "id" : "1",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : {
                "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                "description" : "aear"
            }
        }
    ]
}

/* 1 */
{
    "accountList" : [ 
        {
            "id" : "1100",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : [ 
                {
                    "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                    "description" : "aear"
                }
            ]
        }, 
        {
            "id" : "1200",
            "type" : "xD",
            "currency" : "USD",
            "transactionList" : [ 
                {
                    "onDate" : ISODate("2019-08-16T00:00:00.000Z"),
                    "description" : "aear"
                }
            ]
        }
    ]
}

/* 2 */
{
    "accountList" : [ 
        {
            "id" : "1",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : [ 
                {
                    "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                    "description" : "aear"
                }
            ]
        }
    ]
}

/* 3 */
{
    "accountList" : [ 
        {
            "id" : "00",
            "type" : "xD",
            "currency" : "EUR",
            "transactionList" : [ 
                {
                    "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                    "description" : "aear"
                }, 
                {
                    "onDate" : ISODate("2019-08-26T00:00:00.000Z"),
                    "description" : "aear"
                }
            ]
        }, 
        {
            "id" : "100",
            "type" : "xD",
            "currency" : "USD",
            "transactionList" : [ 
                {
                    "onDate" : ISODate("2019-08-16T00:00:00.000Z"),
                    "description" : "aear"
                }
            ]
        }
    ]
}

/* 1 */
{
    "_id" : ObjectId("5d6435145a0d22d3c86df0c7"),
    "accountList" : [ 
        {
            "id" : "4474",
            "transactionList" : [ 
                {
                    "description" : "aear"
                }, 
                {
                    "description" : "koe"
                }
            ]
        }
    ]
}

/* 2 */
{
    "_id" : ObjectId("5d6435145a0d22d3c86df0d7"),
    "accountList" : [ 
        {
            "id" : "4400",
            "transactionList" : [ 
                {
                    "description" : "aear"
                }, 
                {
                    "description" : "koe"
                }
            ]
        }
    ]
}

/* 3 */
{
    "_id" : ObjectId("5d6435145a0d22d3c86df077"),
    "accountList" : [ 
        {
            "id" : "0000",
            "transactionList" : [ 
                {
                    "description" : "aear"
                }, 
                {
                    "description" : "koe"
                }
            ]
        }
    ]
}

/* 4 */
{
    "_id" : ObjectId("5d6435145a0d22d3c86df1c7"),
    "accountList" : [ 
        {
            "id" : "0101",
            "transactionList" : [ 
                {
                    "description" : "aear"
                }, 
                {
                    "description" : "koe"
                }
            ]
        }
    ]
}

上面的

.find（）

查询的缺点是，它只会在

accountList

中获取第一个匹配对象，如果您在

accountList

中有多个匹配对象用于给定的筛选器，那么您需要使用聚合（此聚合查询也可以用于早期场景，请检查输出是否存在差异）:

输出：

// This first object is best example where you need aggregation

/* 1 */
{
    "_id" : ObjectId("5d6435145a0d22d3c86df1c7"),
    "accountList" : [ 
        {
            "id" : "0101",
            "transactionList" : [ 
                {
                    "description" : "aear"
                }, 
                {
                    "description" : "koe"
                }
            ]
        }, 
        {
            "id" : "1111",
            "transactionList" : [ 
                {
                    "description" : "aear"
                }, 
                {
                    "description" : "koe"
                }
            ]
        }
    ]
}

/* 2 */
{
    "_id" : ObjectId("5d6435145a0d22d3c86df0d7"),
    "accountList" : [ 
        {
            "id" : "4400",
            "transactionList" : [ 
                {
                    "description" : "aear"
                }, 
                {
                    "description" : "koe"
                }
            ]
        }
    ]
}

/* 3 */
{
    "_id" : ObjectId("5d6435145a0d22d3c86df077"),
    "accountList" : [ 
        {
            "id" : "0000",
            "transactionList" : [ 
                {
                    "description" : "aear"
                }, 
                {
                    "description" : "koe"
                }
            ]
        }
    ]
}

/* 4 */
{
    "_id" : ObjectId("5d6435145a0d22d3c86df0c7"),
    "accountList" : [ 
        {
            "id" : "4474",
            "transactionList" : [ 
                {
                    "description" : "aear"
                }, 
                {
                    "description" : "koe"
                }
            ]
        }
    ]
}

---

要实现这一点，您需要使用。我相信此代码将适用于您的情况：

db.report.aggregate([
  { "$match": { "accountList.transactionList.description": { $regex: "aear", $options: "i"} } },
  { "$unwind": "$accountList" },
  { "$unwind": "$accountList.transactionList" },
  { "$match": { "accountList.transactionList.description": { $regex: "aear", $options: "i"} } },
  { "$group": {
      "_id": {
          "_id": "$_id",
          "accountListId": "$accountList.id",
          "accountListType": "$accountList.type",
          "accountListCurrency": "$accountList.currency",
      },
      "transactionList": { "$push": "$accountList.transactionList" }
  }},
  { "$group": {
      "_id": "$_id._id",
      "accountList": {
          "$push": {
              "id": "$_id.accountListId",
              "type": "$_id.accountListType",
              "currency": "$_id.accountListCurrency",
              "transactionList": "$transactionList"
          }
      }
  }}
])

---

我对这项工作表示怀疑，因为要使它适用于许多文件，它不应该包含确切的位置

[0]

和

[4]

。谢谢你的回答！您确定在查询中返回JSON吗？它有重复的数据。您不应该在同一文档中有两个

id

和

transactionList

：

{“id”：“4474”，“transactionList”：[{“description”：“aear”}，{“description”：“koe”}]，“id”：“4475”，“transactionList”：[{“description”：“oho”}，{“description”：“koe”}

。你能把一份文档的实际结构发布到收藏

报告中吗？当然，我会编辑我的答案的。在那里，我完成了编辑。谢谢。如果您没有找到解决方案，请检查我的答案是的，非常感谢！我明天就试试@塞利乌斯廷格：这些对你有用吗？还是有什么问题？这可能有点傻，但我对MongoDB完全是新手，我收到一条消息“消息”：“超出了$group的内存限制，但不允许外部排序。”。Pass allowDiskUse:选择加入为true。“然而，我在第二次尝试后得到了这个结果，第一次我设法得到了结果，但是我得到了完整的输出，而不是‘过滤’的输出。@CeliusStingher:您使用了哪个查询？您的$match是否按预期工作？在应用$match之后，您的数据集有多大？我使用了您在回答中提出的第二个代码。对不起，我一直要求答复。我被分配到一个完全不同的地方，我的注意力现在就在那里。考虑到解释和投入的精力，我对它投了赞成票，加上它可能是正确的，我在实现它时遇到了困难。谢谢，我没有尝试这个答案，因为aear可以以多种形式出现，应该用作正则表达式（aear，aear，aear，laearl，等等），太棒了！非常感谢，我刚刚将regex部分编辑为：{$regex:/.*aear.*/I}