Plates by observer name

All queries are provided with postgres-SQL. Equivalent queries are in the examples using ADQL.

Which observers obtained the largest number of plates in the APPLAUSE DR3? The following query provides top 10 observers by plate count:

SELECT observer,site_name,count(*) AS plate_count
FROM applause_dr3.plate
WHERE observer<>''
GROUP BY observer,site_name
ORDER BY plate_count DESC
LIMIT 10;

This is the result:

How many plates were obtained by Karl Schwarzschild? Let's find out:

SELECT count(*) AS plate_count
FROM applause_dr3.plate
WHERE observer LIKE '%Schwarzschild%';

The result is 48. The following query retrieves dates, format (in centimeters) and preview images of these plates:

SELECT t1.date_orig,t1.plate_format,t2.filename
FROM applause_dr3.plate as t1, applause_dr3.preview as t2
WHERE t1.observer LIKE '%Schwarzschild%'
AND t1.plate_id=t2.plate_id

This is the resulting table:

By clicking on a filename in the table, one can browse the preview images: