daviddoji-cs50/problems/2024/sql/moneyball@20260428T131007.657783175Z

1.sql

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+-- write a SQL query to find the average player salary by year.
+--     Sort by year in descending order.
+--     Round the salary to two decimal places and call the column “average salary”.
+--     Your query should return a table with two columns, one for year and one for average salary.
+SELECT "year", ROUND(AVG("salary"), 2) AS "average salary"
+FROM "salaries"
+GROUP BY "year"
+ORDER BY "year" DESC;

2.sql

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+-- write a SQL query to find Cal Ripken Jr.’s salary history.
+--     Sort by year in descending order.
+--     Your query should return a table with two columns, one for year and one for salary.
+SELECT s."year", s."salary"
+FROM "salaries" AS s
+JOIN "players" AS p
+    ON s."player_id" = p."id"
+WHERE p."first_name" = "Cal" AND p."last_name" LIKE "Ripken%"
+ORDER BY "year" DESC;

3.sql

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+-- write a SQL query to find Ken Griffey Jr.’s home run history.
+--     Sort by year in descending order.
+--     Note that there may be two players with the name “Ken Griffey.” This Ken Griffey was born in 1969.
+--     Your query should return a table with two columns, one for year and one for home runs.
+SELECT perf."year", perf."hr"
+FROM "performances" as perf
+JOIN "players" AS p
+    ON perf."player_id" = p."id"
+WHERE
+    p."first_name" = "Ken"
+    AND
+    p."last_name" LIKE "Griffey%"
+    AND
+    p."birth_year" = "1969"
+ORDER BY "year" DESC;