> ## Documentation Index
> Fetch the complete documentation index at: https://private-7c7dfe99-sync-clickhouse-operator-docs-7e82242.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Validate data correctness after migration

> Learn how to validate the correctness of your data after migrating to ClickHouse Managed Postgres

export const PrivatePreviewBadge = () => {
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            {'Private preview in ClickHouse Cloud'}
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};

<h2 id="data-validation-counts">
  Comparing counts of all tables
</h2>

A simple way to validate the correctness of your data after migration is to compare the counts of all tables in the source and target databases. You can do this by running the following query on both databases:

```sql theme={null}
SELECT table_name, 
       (xpath('/row/cnt/text()', xml_count))[1]::text::bigint AS row_count
FROM (
  SELECT table_name, 
         query_to_xml('SELECT count(*) AS cnt FROM ' || quote_ident(table_name), false, true, '') AS xml_count
  FROM information_schema.tables
  WHERE table_schema = 'public'
) t
ORDER BY table_name;
```