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# How to achieve data read consistency in ClickHouse?

> Learn how to ensure data consistency when reading from ClickHouse, whether you're connected to the same node or a random node.

## Question

I'm writing data into ClickHouse Cloud and need to be able, when reading data, to guarantee that I'm getting the latest complete information.

## Answer

### Talking to the same node

If you are using the native protocol, or a session to do your write/read, you should then be connected to the same replica: in this scenario, you're reading directly from the node where you're writing, and so your read will always be consistent.

### Talking to a random node

If you can't guarantee you're talking to the same node (for example, talking to the node via HTTPS calls which get shuffled via a load balancer), you can either:

A)

1. write your data
2. connect to a new replica
3. run `SYSTEM SYNC REPLICA db.table_name LIGHTWEIGHT`
4. read the latest data

See `SYSTEM` commands [reference](/reference/statements/system#sync-replica)

OR

B) read anytime with sequential consistency

```sql theme={null}
SELECT 
...
SETTINGS select_sequential_consistency = 1
```

Note that when using ClickHouse Cloud and its default [SharedMergeTree](/products/cloud/features/infrastructure/shared-merge-tree) table engine, using `insert_quorum_parallel` is not required — all inserts to SharedMergeTree are quorum inserts (by design).

Using [`SYSTEM SYNC REPLICAS`](/reference/statements/system#sync-replica) or [`select_sequential_consistency`](/reference/settings/session-settings#select_sequential_consistency) will increase the load on ClickHouse Keeper and might have slower performance depending on the load on the service.

The recommended approach is to do the write/read using the same session or the native protocol (sticky connection).