Firebase increase value without reading previous value?
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I'm developing an ios application using Firebase it has huge users. I need to update particular field value in Firebase database based on user's response. Is there a way to increase particular field' value by one(1) without reading its current value. What will happen when several users trying to increase value of same field concurrently?
ios firebase firebase-realtime-database
asked Mar 21 '17 at 4:19
isuruisuru
1,08011028
add a comment |
I'm developing an ios application using Firebase it has huge users. I need to update particular field value in Firebase database based on user's response. Is there a way to increase particular field' value by one(1) without reading its current value. What will happen when several users trying to increase value of same field concurrently?
ios firebase firebase-realtime-database
asked Mar 21 '17 at 4:19
isuruisuru
1,08011028
add a comment |
I'm developing an ios application using Firebase it has huge users. I need to update particular field value in Firebase database based on user's response. Is there a way to increase particular field' value by one(1) without reading its current value. What will happen when several users trying to increase value of same field concurrently?
ios firebase firebase-realtime-database
asked Mar 21 '17 at 4:19
isuruisuru
1,08011028
I'm developing an ios application using Firebase it has huge users. I need to update particular field value in Firebase database based on user's response. Is there a way to increase particular field' value by one(1) without reading its current value. What will happen when several users trying to increase value of same field concurrently?
ios firebase firebase-realtime-database
ios firebase firebase-realtime-database
asked Mar 21 '17 at 4:19
isuruisuru
1,08011028
asked Mar 21 '17 at 4:19
isuruisuru
1,08011028
edited Mar 21 '17 at 4:53
isuru
asked Mar 21 '17 at 4:19
isuruisuru
1,08011028
asked Mar 21 '17 at 4:19
isuruisuru
1,08011028
asked Mar 21 '17 at 4:19
isuruisuru
1,08011028
1,08011028
add a comment |
add a comment |
1 Answer
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From a client app, you cannot increment a value without reading it. If there are multiple writers, the last writer's value overwrites everything else.
If you want to safely increment a value when there are concurrent writers of the same value, use a transaction.
answered Mar 21 '17 at 5:20
Doug StevensonDoug Stevenson
83.9k10100118
add a comment |
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1 Answer
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1 Answer
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active
oldest
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oldest
votes
From a client app, you cannot increment a value without reading it. If there are multiple writers, the last writer's value overwrites everything else.
If you want to safely increment a value when there are concurrent writers of the same value, use a transaction.
answered Mar 21 '17 at 5:20
Doug StevensonDoug Stevenson
83.9k10100118
add a comment |
From a client app, you cannot increment a value without reading it. If there are multiple writers, the last writer's value overwrites everything else.
If you want to safely increment a value when there are concurrent writers of the same value, use a transaction.
answered Mar 21 '17 at 5:20
Doug StevensonDoug Stevenson
83.9k10100118
add a comment |
From a client app, you cannot increment a value without reading it. If there are multiple writers, the last writer's value overwrites everything else.
If you want to safely increment a value when there are concurrent writers of the same value, use a transaction.
answered Mar 21 '17 at 5:20
Doug StevensonDoug Stevenson
83.9k10100118
From a client app, you cannot increment a value without reading it. If there are multiple writers, the last writer's value overwrites everything else.
If you want to safely increment a value when there are concurrent writers of the same value, use a transaction.
answered Mar 21 '17 at 5:20
Doug StevensonDoug Stevenson
83.9k10100118
answered Mar 21 '17 at 5:20
Doug StevensonDoug Stevenson
83.9k10100118
answered Mar 21 '17 at 5:20
Doug StevensonDoug Stevenson
83.9k10100118
answered Mar 21 '17 at 5:20
Doug StevensonDoug Stevenson
83.9k10100118
83.9k10100118
add a comment |
add a comment |
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