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<!-- -->
> WITH
> partitioned AS
> (
> SELECT
> *
> , DATEDIFF(Date, '1970-01-01') - ROW_NUMBER() OVER (ORDER BY Date ASC)
> AS PartID
> FROM
> YourTable
> )
> SELECT
> MIN(Date) AS StartDate
> , COUNT(*) AS DayCount
> FROM
> partitioned
> GROUP BY
> PartID
> HAVING
> COUNT(*) > 1
> ORDER BY
> PartID
> ;
>
> <pre>
> StartDate | DayCount
> :--------- | -------:
> 2021-07-02 | 3
> 2021-07-17 | 2
> 2021-07-21 | 8
> </pre>
*db<>fiddle [here](https://dbfiddle.uk/?rdbms=mariadb_10.6&fiddle=f5ae0b2fb8df18a4b4589146ed481742&hide=3)*
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