Add practice exercise: grade-school

config.json

@@ -218,6 +218,14 @@
         "prerequisites": [],
         "difficulty": 5
       },
+      {
+        "slug": "grade-school",
+        "name": "Grade School",
+        "uuid": "cfa538ab-e637-4836-bb0c-b8fae94fa680",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 5
+      },
       {
         "slug": "house",
         "name": "House",

exercises/practice/grade-school/.docs/instructions.append.md

@@ -0,0 +1,7 @@
+# SQLite-specific instructions
+
+## JSON documentation
+
+[JSON Functions And Operators][json-docs]
+
+[json-docs]: https://www.sqlite.org/json1.html

exercises/practice/grade-school/.docs/instructions.md

@@ -0,0 +1,21 @@
+# Instructions
+
+Given students' names along with the grade they are in, create a roster for the school.
+
+In the end, you should be able to:
+
+- Add a student's name to the roster for a grade:
+  - "Add Jim to grade 2."
+  - "OK."
+- Get a list of all students enrolled in a grade:
+  - "Which students are in grade 2?"
+  - "We've only got Jim right now."
+- Get a sorted list of all students in all grades.
+  Grades should be sorted as 1, 2, 3, etc., and students within a grade should be sorted alphabetically by name.
+  - "Who is enrolled in school right now?"
+  - "Let me think.
+    We have Anna, Barb, and Charlie in grade 1, Alex, Peter, and Zoe in grade 2, and Jim in grade 5.
+    So the answer is: Anna, Barb, Charlie, Alex, Peter, Zoe, and Jim."
+
+Note that all our students only have one name (it's a small town, what do you want?), and each student cannot be added more than once to a grade or the roster.
+If a test attempts to add the same student more than once, your implementation should indicate that this is incorrect.

exercises/practice/grade-school/.meta/config.json

@@ -0,0 +1,18 @@
+{
+  "authors": [
+    "jimmytty"
+  ],
+  "files": {
+    "solution": [
+      "grade-school.sql"
+    ],
+    "test": [
+      "grade-school_test.sql"
+    ],
+    "example": [
+      ".meta/example.sql"
+    ]
+  },
+  "blurb": "Given students' names along with the grade that they are in, create a roster for the school.",
+  "source": "A pairing session with Phil Battos at gSchool"
+}

exercises/practice/grade-school/.meta/example.sql

@@ -0,0 +1,64 @@
+UPDATE "grade-school"
+   SET result = (
+     WITH
+       list (row_id, student) AS (
+         SELECT j.key, JSON_EXTRACT(j.value, '$[0]')
+           FROM JSON_EACH(JSON_EXTRACT(input, '$.students')) j
+       ),
+       duplicates AS (
+         SELECT student, COUNT(*) count FROM list GROUP BY student
+       ),
+       can_add (bool) AS (
+         SELECT (count = 1
+                 OR row_id = (SELECT MIN(row_id)
+                                FROM list
+                               WHERE list.student = tbl.student)
+                )
+           FROM (
+             SELECT row_id, student, count
+               FROM list LEFT JOIN duplicates USING(student)
+           ) tbl
+       )
+     SELECT JSON_GROUP_ARRAY(JSON(IIF(bool = 1, 'true', 'false')))
+       FROM can_add
+   )
+ WHERE property = 'add'
+;
+
+UPDATE "grade-school"
+   SET result = (
+     WITH rows (student, grade) AS (
+       SELECT JSON_EXTRACT(j.value, '$[0]'),
+              JSON_EXTRACT(j.value, '$[1]')
+         FROM JSON_EACH(JSON_EXTRACT(input, '$.students')) j
+     )
+     SELECT JSON_GROUP_ARRAY(student)
+       FROM (
+         SELECT student
+           FROM rows
+          GROUP BY student
+          ORDER BY grade, student
+       )
+   )
+ WHERE property = 'roster'
+;
+
+UPDATE "grade-school"
+   SET result = (
+     WITH list (student, grade) AS (
+       SELECT JSON_EXTRACT(j.value, '$[0]'),
+              JSON_EXTRACT(j.value, '$[1]')
+         FROM JSON_EACH(JSON_EXTRACT(input, '$.students')) j
+     )
+     SELECT JSON_GROUP_ARRAY(student)
+       FROM (
+         SELECT student, JSON_GROUP_ARRAY(grade) grades
+           FROM list
+          GROUP BY student
+          ORDER BY student
+       )
+      WHERE JSON_EXTRACT(grades, '$[0]') =
+            JSON_EXTRACT(input, '$.desiredGrade')
+   )
+ WHERE property = 'grade'
+;

exercises/practice/grade-school/.meta/tests.toml

@@ -0,0 +1,86 @@
+# This is an auto-generated file.
+#
+# Regenerating this file via `configlet sync` will:
+# - Recreate every `description` key/value pair
+# - Recreate every `reimplements` key/value pair, where they exist in problem-specifications
+# - Remove any `include = true` key/value pair (an omitted `include` key implies inclusion)
+# - Preserve any other key/value pair
+#
+# As user-added comments (using the # character) will be removed when this file
+# is regenerated, comments can be added via a `comment` key.
+
+[a3f0fb58-f240-4723-8ddc-e644666b85cc]
+description = "Roster is empty when no student is added"
+
+[9337267f-7793-4b90-9b4a-8e3978408824]
+description = "Add a student"
+
+[6d0a30e4-1b4e-472e-8e20-c41702125667]
+description = "Student is added to the roster"
+
+[73c3ca75-0c16-40d7-82f5-ed8fe17a8e4a]
+description = "Adding multiple students in the same grade in the roster"
+
+[233be705-dd58-4968-889d-fb3c7954c9cc]
+description = "Multiple students in the same grade are added to the roster"
+
+[87c871c1-6bde-4413-9c44-73d59a259d83]
+description = "Cannot add student to same grade in the roster more than once"
+
+[c125dab7-2a53-492f-a99a-56ad511940d8]
+description = "A student can't be in two different grades"
+include = false
+
+[a0c7b9b8-0e89-47f8-8b4a-c50f885e79d1]
+description = "A student can only be added to the same grade in the roster once"
+include = false
+reimplements = "c125dab7-2a53-492f-a99a-56ad511940d8"
+
+[d7982c4f-1602-49f6-a651-620f2614243a]
+description = "Student not added to same grade in the roster more than once"
+reimplements = "a0c7b9b8-0e89-47f8-8b4a-c50f885e79d1"
+
+[e70d5d8f-43a9-41fd-94a4-1ea0fa338056]
+description = "Adding students in multiple grades"
+
+[75a51579-d1d7-407c-a2f8-2166e984e8ab]
+description = "Students in multiple grades are added to the roster"
+
+[7df542f1-57ce-433c-b249-ff77028ec479]
+description = "Cannot add same student to multiple grades in the roster"
+
+[6a03b61e-1211-4783-a3cc-fc7f773fba3f]
+description = "A student cannot be added to more than one grade in the sorted roster"
+include = false
+reimplements = "c125dab7-2a53-492f-a99a-56ad511940d8"
+
+[c7ec1c5e-9ab7-4d3b-be5c-29f2f7a237c5]
+description = "Student not added to multiple grades in the roster"
+reimplements = "6a03b61e-1211-4783-a3cc-fc7f773fba3f"
+
+[d9af4f19-1ba1-48e7-94d0-dabda4e5aba6]
+description = "Students are sorted by grades in the roster"
+
+[d9fb5bea-f5aa-4524-9d61-c158d8906807]
+description = "Students are sorted by name in the roster"
+
+[180a8ff9-5b94-43fc-9db1-d46b4a8c93b6]
+description = "Students are sorted by grades and then by name in the roster"
+
+[5e67aa3c-a3c6-4407-a183-d8fe59cd1630]
+description = "Grade is empty if no students in the roster"
+
+[1e0cf06b-26e0-4526-af2d-a2e2df6a51d6]
+description = "Grade is empty if no students in that grade"
+
+[2bfc697c-adf2-4b65-8d0f-c46e085f796e]
+description = "Student not added to same grade more than once"
+
+[66c8e141-68ab-4a04-a15a-c28bc07fe6b9]
+description = "Student not added to multiple grades"
+
+[c9c1fc2f-42e0-4d2c-b361-99271f03eda7]
+description = "Student not added to other grade for multiple grades"
+
+[1bfbcef1-e4a3-49e8-8d22-f6f9f386187e]
+description = "Students are sorted by name in a grade"

exercises/practice/grade-school/create_fixture.sql

@@ -0,0 +1,11 @@
+DROP TABLE IF EXISTS "grade-school";
+CREATE TABLE "grade-school" (
+  property TEXT NOT NULL,
+  input    TEXT NOT NULL,    -- json object
+  result   TEXT              -- json array
+);
+
+.mode csv
+.import ./data.csv "grade-school"
+
+UPDATE "grade-school" SET result = NULL;

exercises/practice/grade-school/create_test_table.sql

@@ -0,0 +1,39 @@
+DROP TABLE IF EXISTS tests;
+CREATE TABLE IF NOT EXISTS tests (
+  -- uuid and description are taken from the test.toml file
+  uuid TEXT PRIMARY KEY,
+  description TEXT NOT NULL,
+  -- The following section is needed by the online test-runner
+  status TEXT DEFAULT 'fail',
+  message TEXT,
+  output TEXT,
+  test_code TEXT,
+  task_id INTEGER DEFAULT NULL,
+  -- Here are columns for the actual tests
+  property TEXT NOT NULL,
+  input TEXT NOT NULL,          -- json object
+  expected TEXT NOT NULL        -- json array
+);
+
+INSERT INTO tests (uuid, description, property, input, expected)
+VALUES
+('a3f0fb58-f240-4723-8ddc-e644666b85cc', 'Roster is empty when no student is added', 'roster', '{"students":[]}', '[]'),
+('9337267f-7793-4b90-9b4a-8e3978408824', 'Add a student', 'add', '{"students":[["Aimee",2]]}', '[true]'),
+('6d0a30e4-1b4e-472e-8e20-c41702125667', 'Student is added to the roster', 'roster', '{"students":[["Aimee",2]]}', '["Aimee"]'),
+('73c3ca75-0c16-40d7-82f5-ed8fe17a8e4a', 'Adding multiple students in the same grade in the roster', 'add', '{"students":[["Blair",2],["James",2],["Paul",2]]}', '[true,true,true]'),
+('233be705-dd58-4968-889d-fb3c7954c9cc', 'Multiple students in the same grade are added to the roster', 'roster', '{"students":[["Blair",2],["James",2],["Paul",2]]}', '["Blair","James","Paul"]'),
+('87c871c1-6bde-4413-9c44-73d59a259d83', 'Cannot add student to same grade in the roster more than once', 'add', '{"students":[["Blair",2],["James",2],["James",2],["Paul",2]]}', '[true,true,false,true]'),
+('d7982c4f-1602-49f6-a651-620f2614243a', 'Student not added to same grade in the roster more than once', 'roster', '{"students":[["Blair",2],["James",2],["James",2],["Paul",2]]}', '["Blair","James","Paul"]'),
+('e70d5d8f-43a9-41fd-94a4-1ea0fa338056', 'Adding students in multiple grades', 'add', '{"students":[["Chelsea",3],["Logan",7]]}', '[true,true]'),
+('75a51579-d1d7-407c-a2f8-2166e984e8ab', 'Students in multiple grades are added to the roster', 'roster', '{"students":[["Chelsea",3],["Logan",7]]}', '["Chelsea","Logan"]'),
+('7df542f1-57ce-433c-b249-ff77028ec479', 'Cannot add same student to multiple grades in the roster', 'add', '{"students":[["Blair",2],["James",2],["James",3],["Paul",3]]}', '[true,true,false,true]'),
+('c7ec1c5e-9ab7-4d3b-be5c-29f2f7a237c5', 'Student not added to multiple grades in the roster', 'roster', '{"students":[["Blair",2],["James",2],["James",3],["Paul",3]]}', '["Blair","James","Paul"]'),
+('d9af4f19-1ba1-48e7-94d0-dabda4e5aba6', 'Students are sorted by grades in the roster', 'roster', '{"students":[["Jim",3],["Peter",2],["Anna",1]]}', '["Anna","Peter","Jim"]'),
+('d9fb5bea-f5aa-4524-9d61-c158d8906807', 'Students are sorted by name in the roster', 'roster', '{"students":[["Peter",2],["Zoe",2],["Alex",2]]}', '["Alex","Peter","Zoe"]'),
+('180a8ff9-5b94-43fc-9db1-d46b4a8c93b6', 'Students are sorted by grades and then by name in the roster', 'roster', '{"students":[["Peter",2],["Anna",1],["Barb",1],["Zoe",2],["Alex",2],["Jim",3],["Charlie",1]]}', '["Anna","Barb","Charlie","Alex","Peter","Zoe","Jim"]'),
+('5e67aa3c-a3c6-4407-a183-d8fe59cd1630', 'Grade is empty if no students in the roster', 'grade', '{"students":[],"desiredGrade":1}', '[]'),
+('1e0cf06b-26e0-4526-af2d-a2e2df6a51d6', 'Grade is empty if no students in that grade', 'grade', '{"students":[["Peter",2],["Zoe",2],["Alex",2],["Jim",3]],"desiredGrade":1}', '[]'),
+('2bfc697c-adf2-4b65-8d0f-c46e085f796e', 'Student not added to same grade more than once', 'grade', '{"students":[["Blair",2],["James",2],["James",2],["Paul",2]],"desiredGrade":2}', '["Blair","James","Paul"]'),
+('66c8e141-68ab-4a04-a15a-c28bc07fe6b9', 'Student not added to multiple grades', 'grade', '{"students":[["Blair",2],["James",2],["James",3],["Paul",3]],"desiredGrade":2}', '["Blair","James"]'),
+('c9c1fc2f-42e0-4d2c-b361-99271f03eda7', 'Student not added to other grade for multiple grades', 'grade', '{"students":[["Blair",2],["James",2],["James",3],["Paul",3]],"desiredGrade":3}', '["Paul"]'),
+('1bfbcef1-e4a3-49e8-8d22-f6f9f386187e', 'Students are sorted by name in a grade', 'grade', '{"students":[["Franklin",5],["Bradley",5],["Jeff",1]],"desiredGrade":5}', '["Bradley","Franklin"]');

exercises/practice/grade-school/data.csv

@@ -0,0 +1,20 @@
+roster,"{""students"":[]}",
+add,"{""students"":[[""Aimee"",2]]}",
+roster,"{""students"":[[""Aimee"",2]]}",
+add,"{""students"":[[""Blair"",2],[""James"",2],[""Paul"",2]]}",
+roster,"{""students"":[[""Blair"",2],[""James"",2],[""Paul"",2]]}",
+add,"{""students"":[[""Blair"",2],[""James"",2],[""James"",2],[""Paul"",2]]}",
+roster,"{""students"":[[""Blair"",2],[""James"",2],[""James"",2],[""Paul"",2]]}",
+add,"{""students"":[[""Chelsea"",3],[""Logan"",7]]}",
+roster,"{""students"":[[""Chelsea"",3],[""Logan"",7]]}",
+add,"{""students"":[[""Blair"",2],[""James"",2],[""James"",3],[""Paul"",3]]}",
+roster,"{""students"":[[""Blair"",2],[""James"",2],[""James"",3],[""Paul"",3]]}",
+roster,"{""students"":[[""Jim"",3],[""Peter"",2],[""Anna"",1]]}",
+roster,"{""students"":[[""Peter"",2],[""Zoe"",2],[""Alex"",2]]}",
+roster,"{""students"":[[""Peter"",2],[""Anna"",1],[""Barb"",1],[""Zoe"",2],[""Alex"",2],[""Jim"",3],[""Charlie"",1]]}",
+grade,"{""students"":[],""desiredGrade"":1}",
+grade,"{""students"":[[""Peter"",2],[""Zoe"",2],[""Alex"",2],[""Jim"",3]],""desiredGrade"":1}",
+grade,"{""students"":[[""Blair"",2],[""James"",2],[""James"",2],[""Paul"",2]],""desiredGrade"":2}",
+grade,"{""students"":[[""Blair"",2],[""James"",2],[""James"",3],[""Paul"",3]],""desiredGrade"":2}",
+grade,"{""students"":[[""Blair"",2],[""James"",2],[""James"",3],[""Paul"",3]],""desiredGrade"":3}",
+grade,"{""students"":[[""Franklin"",5],[""Bradley"",5],[""Jeff"",1]],""desiredGrade"":5}",

exercises/practice/grade-school/grade-school.sql

@@ -0,0 +1,8 @@
+-- Schema:
+-- CREATE TABLE "grade-school" (
+--   property TEXT NOT NULL,
+--   input    TEXT NOT NULL,    -- json object
+--   result   TEXT              -- json array
+-- );
+--
+-- Task: update the grade-school and update the result column based on the property and the input.

exercises/practice/grade-school/grade-school_test.sql

@@ -0,0 +1,53 @@
+-- Create database:
+.read ./create_fixture.sql
+
+-- Read user student solution and save any output as markdown in user_output.md:
+.mode markdown
+.output user_output.md
+.read ./grade-school.sql
+.output
+
+-- Create a clean testing environment:
+.read ./create_test_table.sql
+
+-- Comparison of user input and the tests updates the status for each test:
+UPDATE tests
+   SET status = 'pass'
+  FROM (SELECT property, input, result FROM "grade-school") AS actual
+ WHERE (actual.property, actual.input, actual.result) =
+       ( tests.property,  tests.input,  tests.expected)
+;
+
+-- Update message for failed tests to give helpful information:
+UPDATE tests
+   SET message = (
+         'Result for "'
+         || PRINTF('property=%s, input=%s', tests.property, tests.input)
+         || '"' || ' is <' || COALESCE(actual.result, 'NULL')
+         || '> but should be <' || tests.expected || '>'
+  )
+  FROM (SELECT property, input, result FROM "grade-school") AS actual
+ WHERE (actual.property, actual.input) = (tests.property, tests.input)
+   AND tests.status = 'fail';
+
+-- Save results to ./output.json (needed by the online test-runner)
+.mode json
+.once './output.json'
+SELECT
+  description,
+  status,
+  message,
+  output,
+  test_code,
+  task_id
+FROM
+  tests;
+
+-- Display test results in readable form for the student:
+.mode table
+SELECT
+  description,
+  status,
+  message
+FROM
+  tests;