daviddoji-cs50/problems/2024/sql/dese@20260427T154107.177384157Z

12.sql

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+-- write a SQL query to find public school districts with above-average per-pupil expenditures and
+-- an above-average percentage of teachers rated “exemplary”. Your query should return the districts’ names,
+-- along with their per-pupil expenditures and percentage of teachers rated exemplary. Sort the results first by
+-- the percentage of teachers rated exemplary (high to low), then by the per-pupil expenditure (high to low).
+
+-- You might find it helpful to know that subqueries can be inserted into most any part of a SQL query,
+-- including conditions. For instance, the following is valid SQL syntax:
+
+-- SELECT "column" FROM "table"
+-- WHERE "column" > (
+--     SELECT AVG("column")
+--     FROM "table"
+-- );
+
+SELECT
+    d."name",
+    e."per_pupil_expenditure",
+    s."exemplary"
+FROM "districts" AS d
+JOIN "expenditures" AS e
+    ON d."id" = e."district_id"
+JOIN "staff_evaluations" AS s
+    ON d."id" = s."district_id"
+WHERE d."type" = 'Public School District'
+  AND e."per_pupil_expenditure" > (
+      SELECT AVG("per_pupil_expenditure")
+      FROM "expenditures"
+  )
+  AND s."exemplary" > (
+      SELECT AVG("exemplary")
+      FROM "staff_evaluations"
+  )
+ORDER BY s."exemplary" DESC, e."per_pupil_expenditure" DESC;