Javascript 在Firestore中单独查询而不是多个Where子句
我想用两个参数查询firebase firestore数据收集 收藏:动物Javascript 在Firestore中单独查询而不是多个Where子句,javascript,node.js,firebase,nosql,google-cloud-firestore,Javascript,Node.js,Firebase,Nosql,Google Cloud Firestore,我想用两个参数查询firebase firestore数据收集 收藏:动物 "animals": { "1": { "animal1": "cat", "animal2": "dog", "animal3": "", "animal4": "" }, "2": { "animal1": "dog", "animal2": "cat", "animal3": "", "animal4"
"animals": {
"1": {
"animal1": "cat",
"animal2": "dog",
"animal3": "",
"animal4": ""
},
"2": {
"animal1": "dog",
"animal2": "cat",
"animal3": "",
"animal4": ""
},
"3": {
"animal1": "cat",
"animal2": "bird",
"animal3": "dog",
"animal4": ""
},
"4": {
"animal1": "wolf",
"animal2": "dog",
"animal3": "bird",
"animal4": ""
},
"5": {
"animal1": "turtle",
"animal2": "dog",
"animal3": "wolf",
"animal4": "cat"
},
"6": {
"animal1": "dog",
"animal2": "wolf",
"animal3": "turtle",
"animal4": "bear"
},
"7": {
"animal1": "spider",
"animal2": "beatle",
"animal3": "butterfly",
"animal4": "Cat"
}
}
我想要获得包括猫和狗的列表数据。
有消息
逻辑或查询。在这种情况下,您应该为每个OR条件创建一个单独的查询,并在应用程序中合并查询结果。
我不知道我需要多少单独的查询
let param1 = 'cat';
let param2 = 'dog';
let query1 = db.collection('animals').where('animal1', '==', param1);
let query2 = db.collection('animals').where('animal2', '==', param1);
let query3 = db.collection('animals').where('animal3', '==', param2);
let query4 = db.collection('animals').where('animal4', '==', param3);
正如您所指出的,“您应该为每个或条件创建一个单独的查询,并在应用程序中合并查询结果”。因为在数据模型中,有4个字段(animal1
到animal4
),所以需要为要测试的每个参数
值创建4个查询
因此,对于2个参数,如下所示:
let param1 = 'cat';
let param2 = 'dog';
let query1 = db.collection('animals').where("animalArray", "array-contains", param1);
let query2 = db.collection('animals').where("animalArray", "array-contains", param2);
您必须合并2*4查询的结果
如果您更改数据模型并使用数组存储动物
值,则有可能减少此数字。然后可以利用数组\u contains
操作符
提议的数据模型:
"animals": {
"1": {
"animalArray":
[
0: "cat",
1: "dog"
]
},
"2": {
"animalArray":
[
0: "turtle",
1: "dog",
2: "wolf",
3: "bear",
]
}
.....
}
在我们的两个参数的示例中,您只需要两个查询,如下所示:
let param1 = 'cat';
let param2 = 'dog';
let query1 = db.collection('animals').where("animalArray", "array-contains", param1);
let query2 = db.collection('animals').where("animalArray", "array-contains", param2);
谢谢你,雷诺。问题是我的数据模型结构。使用数组和数组包含似乎更好。另外,2*4查询对于性能来说非常繁重。。。