Firebase中多个where子句的查询

Question

下面是我开始使用的代码，但我不确定该去哪里。看看这个问题的解决方案，我似乎需要根据下面的查询下载数据，然后在客户端对其进行排序。我似乎做不到的事

  firebase.database().ref('tshirts')
    .orderByChild('brandStartsWith')
    .equalTo('A')
    .once('value', function (snapshot) {
       console.log(snapshot.val())
   })

Answer 1

您需要创建一个组合键，因为一次只能执行一个where子句。

{
    "tShirts" : {
        "brandStartsWith" : 'A',
        "salesRank" : 5
        "brandStartsWith_salesRank" = 'A_00005' //pad for as many sales ranks as you have
    }, {
        "brandStartsWith" : 'B',
        "salesRank" : 108
        "brandStartsWith_salesRank" = 'B_00108' //pad for as many sales ranks as you have
    }, {
        "brandStartsWith" : 'C',
        "salesRank" : 52
        "brandStartsWith_salesRank" = 'C_00052' //pad for as many sales ranks as you have
    }
}

这将允许您执行以下查询：

firebase.database().ref('tshirts')
    .orderByChild('brandStartsWith_salesRank')
    .startAt('A_00001')
    .endAt('A_00100')
    .once('value', function (snapshot) {
        console.log(snapshot.val())
    })

不要忘记将规则更新为.indexbrandStartsWith_salesRank