Checking whether two tables have the same number of rows never finishes. What's wrong with this query?

robertspierre 0
Viewed 24

I'm using SQLite 3.39.3.

I came up with this query to check whether two tables have the same number of rows:

SELECT COUNT(a.auth_id)=COUNT(b.auth_scopus_id) FROM auth_subject_areas_mapping AS a, auth_subject_areas_mapping_old AS b;

But the query never finishes. EXPLAIN QUERY PLAN gives me:

enter image description here

Questions:

  1. What's wrong with my query?
  2. What is the correct way in SQLite to check whether two tables have the same number of rows?
sqlite
1 Answers
WITH
    acount AS (SELECT count(*) AS a FROM auth_subject_areas_mapping),
    bcount AS (SELECT count(*) AS b FROM auth_subject_areas_mapping_old)
SELECT a = b FROM acount, bcount;
PChemGuy0
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