From looks like: From temptable, table2 without a join, can someone explain how this works?

Question

Hi all,

I've found an old query which I'm trying to understand. I've a question about the FROM part. I understand that the temporary table is a key-valuepair. But I don't understand what happens in the from part. Because it returns the dutch names of the week (created in the key-valuepair), but why? The query looks like this:

WITH
  days AS (
   SELECT "map"(ARRAY['Sunday','Monday','Tuesday','Wednesday','Thursday','Friday','Saturday'], 
   ARRAY['Zondag','Maandag','Dinsdag','Woensdag','Donderdag','Vrijdag','Zaterdag']) "dagen"

)

SELECT
   , "date"("tabel1"."datumtijd") "date"
   , "dagen"["date_format"("date"("tabel1"), '%W')] "days"
      FROM
     days
   , "tabel1"
   LEFT JOIN "tabel2 "ON (....

Accepted Answer

The FROM part specifies the tables being joined. Run an EXPLAIN and you should get more information about the query execution.

From looks like: From temptable, table2 without a join, can someone explain how this works?

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