sql/queries: add chapter-count-by-city.sql

src/sql/queries/chapter-count-by-city.sql

@@ -0,0 +1,22 @@
+-- | DESCRIPTION
+--
+-- This query groups the number of chapters to one of two
+-- cities they were revealed in: either Makkah, or Medina.
+--
+-- | EXAMPLE RESULT SET
+--
+--     city     chapters
+--   -------    --------
+--    Madinah    28
+--    Makkah     86
+
+SELECT
+  chapters.city,
+  COUNT(chapters.city) AS chapters
+from
+  chapters
+where
+  chapters.quran_id = 1
+GROUP BY
+  chapters.city;
+