how to set two query in firebase option quer code example
Example 1: how to query in firestore
db.collection("cities").where("capital", "==", true)
.get()
.then(function(querySnapshot) {
querySnapshot.forEach(function(doc) {
// doc.data() is never undefined for query doc snapshots
console.log(doc.id, " => ", doc.data());
});
})
.catch(function(error) {
console.log("Error getting documents: ", error);
});
Example 2: multiple query at once in firebase
function doSomething(...){
let result1 = [];
let result2 = [];
admin.firestore().collection('...').where('some condition').get()
.then((results: any)=>{
results.forEach((element: any)=>{
if(some other condition){
result1.push(element);
}
})
.catch((error: any)=>{//log the error});
admin.firestore().collection('...').where('yet another condition').orderBy(...).get()
.then((results: any)=>{
results.forEach((element: any)=>{
result2.push(func(element)) //func is some manipulation
})
.catch((error: any)=>{//log the error});
return makeCalculation(result1, result2);
}
Example 3: firebase query multiple keys
var keys = [
"-Ke1uhoT3gpHR_VsehIv",
"-Ke8qAECkZC9ygGW3dEJ",
"-Ke8qMU7OEfUnuXSlhhl"
];
var promises = keys.map(function(key) {
return firebase.database().ref("/items/").child(key).once("value");
});
Promise.all(promises).then(function(snapshots) {
snapshots.forEach(function(snapshot) {
console.log(snapshot.key+": "+snapshot.val());
});
});