How to get a key with knowing only one value - firebase

Question

I've been going back and forward with this thing for a week now and can't get to a solution with it. Basically I want to remove something from firebase database but the thing is that I don't know what key is. So I added a server timestamp which should be a unique thing and now I would like to find that timestamp in the database and remove that child/node, however u call this, to which that timestamp belongs.
This part creates views with the info from the database and when I would click on that image I would like to remove it from the database.
<View style={styles.itemsList}>
{this.props.items.map((item, index) => {
if (item.ttype == 0) {
return (
<View key={index} style={styles.viewHolderNegative}>
<TouchableOpacity onPress={() => this.removeSelected(item.timestamp)}>
<Image source={require('./assets/remove24.png')}></Image>
</TouchableOpacity>
<Text style={styles.textTransaction}>{item.name}</Text>
<Text style={[styles.textTransaction, { fontSize: 20 }]}>{item.date}</Text>
</View>
);
} else if (item.ttype == 1) {
return (
<View key={index} style={styles.viewHolderPositive}>
<TouchableOpacity onPress={() => this.removeSelected(item.timestamp)}>
<Image source={require('./assets/remove24.png')}></Image>
</TouchableOpacity>
<Text style={styles.textTransaction}>{item.name}</Text>
<Text style={[styles.textTransaction, { fontSize: 20 }]}>{item.date}</Text>
</View>
);
}
})}
</View>

Answer 1

I assume that you are aware of firebase methods, if not then check firebase docs for react-native,
you can achieve removing an item by remove() method but you will have to acknowledge which item to remove.
for that, you will have to give key in child(key) method.
see this,
firebase.database().ref('ITEMS').child('KEY').remove();
ITEMS is the collection name and KEY is your timestamp.