MongoDB檢查文檔/記錄是否存在

Question

我試圖將.find（{}）與mongogb結合使用，但不幸的是，它沒有給我期望的響應，我不確定如何檢查文檔是否存在？ 我想做的是說：

如果文檔確實存在，則執行某項操作。.IE發送回響應，但如果文檔不存在，則創建該文檔，

不幸的是，我知道一個文檔不存在，但是它一定是用'if（docs）'來拾取錯誤的東西，但是當我將其更改為其他內容時，它總是會創建記錄！

編碼：

addRefund : (refundCalc, callback) => {
    order_number = refundCalc.refundDetails.customer_details.order.order_number;
    dbconnect.createConnection()
    refund.find({order_number: order_number}, (err, docs) => {
        if (docs) {
            console.log('docss!!!!!!!!!!!!!' + JSON.stringify(docs));
            console.log('calling within error!!!!!!')
            let notStored = {"refundDocStored" : "False"}
            callback(notStored)
            dbconnect.closeConnection();
        }
        else {
            refund.create(refundCalc).then((refunddoc) => {
               let filestored = {"refundDocStored" : "True"}                              
               dbconnect.closeConnection();
               callback(filestored)
            }).catch((err)=> {
                console.log(err);
                dbconnect.closeConnection();
            })
        }
    })
},

模式：

const refundSchema = new Schema({
domain : { type: String},
refundDetails : {
    customer_details : [],
    refund : {
        shipping : {
            amount : { type: Number},
            tax : {type : Number},
            maximum_refundable : {type : Number}
        },
        refund_line_items: [],
        transactions: []   
    }
}

}）;

訂單存儲在退款詳細信息中，如下所示：

"refundDetails":{"customer_details":{"order":{"order_number":1021

它似乎根本不適合我！ 如果文件存在，我似乎無法真正證明它確實存在？

任何幫助將是巨大的，謝謝！

Answer 1

您使用了錯誤的搜索查詢。 您正在搜索order_number，它是另一個對象內部的一個對象的屬性。 您必須在查詢中引用order_number的完整路徑，即{"refundCalc.refundDetails.customer_details.order.order_number" : order_number}

addRefund : (refundCalc, callback) => {
    order_number = refundCalc.refundDetails.customer_details.order.order_number;
    dbconnect.createConnection()
    refund.find({"refundCalc.refundDetails.customer_details.order.order_number": order_number}, (err, docs) => {
        if (docs) {
            console.log('docss!!!!!!!!!!!!!' + JSON.stringify(docs));
            console.log('calling within error!!!!!!')
            let notStored = {"refundDocStored" : "False"}
            callback(notStored)
            dbconnect.closeConnection();
        }
        else {
            refund.create(refundCalc).then((refunddoc) => {
               let filestored = {"refundDocStored" : "True"}                              
               dbconnect.closeConnection();
               callback(filestored)
            }).catch((err)=> {
                console.log(err);
                dbconnect.closeConnection();
            })
        }
    })
},