Redshift internal queries

Question

I see below queries in the stl_query table, what do they mean?  
  
small table conversion: 3623965                                               
small table validation: select sum(rows), sum(sorted_rows) from stv_tbl_perm where table = {tableid};

Accepted Answer

Redshift checks the status of AUTO distributed tables periodically and converts the distribution type as needed. https://docs.aws.amazon.com/redshift/latest/dg/c_choosing_dist_sort.html  
> **AUTO distribution**  
> With AUTO distribution, Amazon Redshift assigns an optimal distribution style based on the size of the table data. For example, Amazon Redshift initially assigns ALL distribution to a small table, then changes to EVEN distribution when the table grows larger. When a table is changed from ALL to EVEN distribution, storage utilization might change slightly. The change in distribution occurs in the background, in a few seconds. Amazon Redshift never changes the distribution style from EVEN to ALL. To view the distribution style applied to a table, query the PG_CLASS_INFO system catalog view. For more information, see Viewing Distribution Styles. If you don't specify a distribution style with the CREATE TABLE statement, Amazon Redshift applies AUTO distribution.

Answer

I have no idea, but it makes me think of VACUUM checking to see if it should skip a table or not (because it's already sorted enough).

Redshift internal queries

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