Charles KWON OhJun
486e466592
Major changes since last commit: - FiveSql2 SQL:1999 engine (10,458 LOC) — 43/43 ALL PASS - 21 compiler/runtime bugs fixed (short-circuit AND/OR, FOR LOOP, etc.) - @byref pass-by-reference via RefCell pattern - Mutable closure capture (EnsureLocalRef + RefCell sharing) - RTL: 400 → 479 functions (+79: file, string, datetime, hash, UTF-8) - DateTime/Timestamp fully working (hb_DateTime, hb_Hour/Min/Sec, display) - Reserved word guard (39 keywords blocked from function calls) - AEval arg order fix (element before index) - Closure capture redecl fix (unique _cap_ names per block) - Hash/string indexing in ArrayPush/ArrayPop - Harbour compat test suite: 51/51 - 4 docs: Porting Report, Implementation Plan, Optimization Plan, Commercialization Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
550 lines
20 KiB
Plaintext
550 lines
20 KiB
Plaintext
/*
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* test_sql_challenge.prg — Real-world SQL Challenge Queries
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*
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* These are the kind of queries seen in SQL coding interviews,
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* LeetCode/HackerRank challenges, and production analytics.
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* Tests FiveSql's ability to handle complex, nested, multi-feature queries.
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*
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* Copyright (c) 2025-2026 Charles KWON (Charles KWON OhJun)
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* Email: charleskwonohjun@gmail.com
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* All rights reserved.
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*/
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#include "FiveSqlDef.ch"
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#include "hbclass.ch"
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STATIC s_nPass := 0
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STATIC s_nFail := 0
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STATIC s_nTotal := 0
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PROCEDURE Main()
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? "================================================================"
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? " SQL Challenge Queries — Real-world Stress Test"
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? "================================================================"
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?
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SetupData()
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Challenge01_SecondHighestSalary()
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Challenge02_NthHighestPerDept()
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Challenge03_ConsecutiveNumbers()
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Challenge04_DeptVsCompanyAvg()
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Challenge05_EmployeeManagerSalary()
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Challenge06_CumulativeSum()
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Challenge07_GapAnalysis()
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Challenge08_PivotSimulation()
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Challenge09_SelfJoinHierarchy()
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Challenge10_TopNPerGroup()
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Challenge11_RunningRank()
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Challenge12_YoYGrowth()
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Challenge13_IslandGap()
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Challenge14_MedianApprox()
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Challenge15_TripleNested()
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CleanupData()
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?
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? "================================================================"
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? " Pass: " + hb_ntos( s_nPass )
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? " Fail: " + hb_ntos( s_nFail )
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? " Total: " + hb_ntos( s_nTotal )
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? " Rate: " + hb_ntos( Int( s_nPass * 100 / Max( s_nTotal, 1 ) ) ) + "%"
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? "================================================================"
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RETURN
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STATIC FUNCTION Assert( cLabel, lOK )
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s_nTotal++
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IF lOK
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s_nPass++
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? " PASS: " + cLabel
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ELSE
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s_nFail++
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? " FAIL: " + cLabel
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ENDIF
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RETURN lOK
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STATIC FUNCTION Rows( aR )
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IF ValType( aR ) == "A" .AND. Len( aR ) >= 2 .AND. ValType( aR[ 2 ] ) == "A"
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RETURN Len( aR[ 2 ] )
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ENDIF
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RETURN 0
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STATIC FUNCTION Cell( aR, nRow, nCol )
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IF ValType( aR ) == "A" .AND. Len( aR ) >= 2 .AND. ;
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nRow <= Len( aR[ 2 ] ) .AND. nCol <= Len( aR[ 2 ][ nRow ] )
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RETURN aR[ 2 ][ nRow ][ nCol ]
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ENDIF
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RETURN NIL
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STATIC FUNCTION SetupData()
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/* employees: 12 rows with hierarchy + varied salaries */
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FErase( "employees.dbf" )
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dbCreate( "employees.dbf", { ;
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{ "ID", "N", 10, 0 }, ;
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{ "NAME", "C", 20, 0 }, ;
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{ "DEPT", "C", 15, 0 }, ;
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{ "SALARY", "N", 12, 2 }, ;
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{ "MGR_ID", "N", 10, 0 }, ;
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{ "HIRE_YEAR","N", 4, 0 } ;
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} )
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USE employees.dbf NEW EXCLUSIVE
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dbAppend() ; FieldPut(1, 1) ; FieldPut(2,"Alice") ; FieldPut(3,"Eng") ; FieldPut(4,9000) ; FieldPut(5,0) ; FieldPut(6,2020)
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dbAppend() ; FieldPut(1, 2) ; FieldPut(2,"Bob") ; FieldPut(3,"Eng") ; FieldPut(4,8000) ; FieldPut(5,1) ; FieldPut(6,2020)
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dbAppend() ; FieldPut(1, 3) ; FieldPut(2,"Charlie"); FieldPut(3,"Eng") ; FieldPut(4,8000) ; FieldPut(5,1) ; FieldPut(6,2021)
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dbAppend() ; FieldPut(1, 4) ; FieldPut(2,"Diana") ; FieldPut(3,"Sales") ; FieldPut(4,7500) ; FieldPut(5,0) ; FieldPut(6,2019)
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dbAppend() ; FieldPut(1, 5) ; FieldPut(2,"Eve") ; FieldPut(3,"Sales") ; FieldPut(4,6000) ; FieldPut(5,4) ; FieldPut(6,2021)
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dbAppend() ; FieldPut(1, 6) ; FieldPut(2,"Frank") ; FieldPut(3,"Sales") ; FieldPut(4,5500) ; FieldPut(5,4) ; FieldPut(6,2022)
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dbAppend() ; FieldPut(1, 7) ; FieldPut(2,"Grace") ; FieldPut(3,"Mktg") ; FieldPut(4,7000) ; FieldPut(5,0) ; FieldPut(6,2020)
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dbAppend() ; FieldPut(1, 8) ; FieldPut(2,"Henry") ; FieldPut(3,"Mktg") ; FieldPut(4,6500) ; FieldPut(5,7) ; FieldPut(6,2021)
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dbAppend() ; FieldPut(1, 9) ; FieldPut(2,"Ivy") ; FieldPut(3,"HR") ; FieldPut(4,6000) ; FieldPut(5,0) ; FieldPut(6,2019)
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dbAppend() ; FieldPut(1,10) ; FieldPut(2,"Jack") ; FieldPut(3,"HR") ; FieldPut(4,5000) ; FieldPut(5,9) ; FieldPut(6,2022)
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dbAppend() ; FieldPut(1,11) ; FieldPut(2,"Kate") ; FieldPut(3,"Eng") ; FieldPut(4,7000) ; FieldPut(5,2) ; FieldPut(6,2022)
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dbAppend() ; FieldPut(1,12) ; FieldPut(2,"Leo") ; FieldPut(3,"Eng") ; FieldPut(4,9000) ; FieldPut(5,2) ; FieldPut(6,2023)
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dbCommit()
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CLOSE ALL
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/* orders: 20 rows with amounts and years */
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FErase( "orders.dbf" )
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dbCreate( "orders.dbf", { ;
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{ "ID", "N", 10, 0 }, ;
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{ "EMP_ID", "N", 10, 0 }, ;
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{ "AMOUNT", "N", 12, 2 }, ;
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{ "ORD_YEAR", "N", 4, 0 } ;
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} )
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USE orders.dbf NEW EXCLUSIVE
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dbAppend() ; FieldPut(1, 1) ; FieldPut(2, 1) ; FieldPut(3,2500) ; FieldPut(4,2022)
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dbAppend() ; FieldPut(1, 2) ; FieldPut(2, 1) ; FieldPut(3,3000) ; FieldPut(4,2023)
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dbAppend() ; FieldPut(1, 3) ; FieldPut(2, 2) ; FieldPut(3,1500) ; FieldPut(4,2022)
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dbAppend() ; FieldPut(1, 4) ; FieldPut(2, 2) ; FieldPut(3,2000) ; FieldPut(4,2023)
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dbAppend() ; FieldPut(1, 5) ; FieldPut(2, 4) ; FieldPut(3,4000) ; FieldPut(4,2022)
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dbAppend() ; FieldPut(1, 6) ; FieldPut(2, 4) ; FieldPut(3,3500) ; FieldPut(4,2023)
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dbAppend() ; FieldPut(1, 7) ; FieldPut(2, 5) ; FieldPut(3,1000) ; FieldPut(4,2022)
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dbAppend() ; FieldPut(1, 8) ; FieldPut(2, 5) ; FieldPut(3,1200) ; FieldPut(4,2023)
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dbAppend() ; FieldPut(1, 9) ; FieldPut(2, 7) ; FieldPut(3,3000) ; FieldPut(4,2022)
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dbAppend() ; FieldPut(1,10) ; FieldPut(2, 7) ; FieldPut(3,2800) ; FieldPut(4,2023)
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dbAppend() ; FieldPut(1,11) ; FieldPut(2, 9) ; FieldPut(3, 800) ; FieldPut(4,2022)
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dbAppend() ; FieldPut(1,12) ; FieldPut(2, 9) ; FieldPut(3, 900) ; FieldPut(4,2023)
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dbAppend() ; FieldPut(1,13) ; FieldPut(2,11) ; FieldPut(3,1800) ; FieldPut(4,2023)
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dbAppend() ; FieldPut(1,14) ; FieldPut(2,12) ; FieldPut(3,2200) ; FieldPut(4,2023)
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dbAppend() ; FieldPut(1,15) ; FieldPut(2, 3) ; FieldPut(3,1700) ; FieldPut(4,2022)
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dbAppend() ; FieldPut(1,16) ; FieldPut(2, 3) ; FieldPut(3,2100) ; FieldPut(4,2023)
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dbAppend() ; FieldPut(1,17) ; FieldPut(2, 6) ; FieldPut(3, 600) ; FieldPut(4,2023)
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dbAppend() ; FieldPut(1,18) ; FieldPut(2, 8) ; FieldPut(3,1400) ; FieldPut(4,2022)
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dbAppend() ; FieldPut(1,19) ; FieldPut(2, 8) ; FieldPut(3,1600) ; FieldPut(4,2023)
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dbAppend() ; FieldPut(1,20) ; FieldPut(2,10) ; FieldPut(3, 500) ; FieldPut(4,2023)
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dbCommit()
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CLOSE ALL
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RETURN NIL
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STATIC FUNCTION CleanupData()
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dbCloseAll()
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FErase( "employees.dbf" )
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FErase( "orders.dbf" )
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RETURN NIL
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/* ====================================================================
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* Challenge 1: Second Highest Salary (LeetCode #176)
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* Find the second highest distinct salary.
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* ==================================================================== */
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STATIC PROCEDURE Challenge01_SecondHighestSalary()
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LOCAL aR
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dbCloseAll()
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BEGIN SEQUENCE
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aR := five_SQL( ;
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"SELECT MAX(salary) AS second_highest " + ;
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"FROM employees " + ;
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"WHERE salary < (SELECT MAX(salary) FROM employees)" )
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/* Max=9000, second=8000 */
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Assert( "1. Second Highest Salary = 8000", ;
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Rows( aR ) == 1 .AND. Cell( aR, 1, 1 ) == 8000 )
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RECOVER
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s_nTotal++ ; s_nFail++ ; ? " FAIL: 1. Second Highest (exception)"
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END SEQUENCE
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RETURN
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/* ====================================================================
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* Challenge 2: Nth Highest Salary Per Department (LeetCode #185 variant)
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* Top 2 earners per department using DENSE_RANK.
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* ==================================================================== */
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STATIC PROCEDURE Challenge02_NthHighestPerDept()
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LOCAL aR
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dbCloseAll()
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BEGIN SEQUENCE
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aR := five_SQL( ;
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"WITH ranked AS (" + ;
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"SELECT name, dept, salary, " + ;
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"DENSE_RANK() OVER (PARTITION BY dept ORDER BY salary DESC) AS rnk " + ;
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"FROM employees" + ;
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") SELECT name, dept, salary FROM ranked WHERE rnk <= 2 ORDER BY dept, salary DESC" )
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/* Eng: Alice=9000,Leo=9000(tie),Bob=8000,Charlie=8000(tie) but DENSE_RANK top 2 = rank1+rank2
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* Sales: Diana=7500, Eve=6000
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* Mktg: Grace=7000, Henry=6500
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* HR: Ivy=6000, Jack=5000 */
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Assert( "2. Top 2 per dept (DENSE_RANK)", Rows( aR ) >= 8 )
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RECOVER
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s_nTotal++ ; s_nFail++ ; ? " FAIL: 2. Top 2 per dept (exception)"
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END SEQUENCE
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RETURN
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/* ====================================================================
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* Challenge 3: Consecutive same values (LeetCode #180 variant)
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* Find employees who share the same salary as at least one other person.
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* ==================================================================== */
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STATIC PROCEDURE Challenge03_ConsecutiveNumbers()
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LOCAL aR
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dbCloseAll()
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BEGIN SEQUENCE
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aR := five_SQL( ;
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"SELECT DISTINCT salary FROM employees " + ;
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"WHERE salary IN (" + ;
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" SELECT salary FROM employees GROUP BY salary HAVING COUNT(*) > 1" + ;
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") ORDER BY salary DESC" )
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/* 9000 (Alice,Leo), 8000 (Bob,Charlie), 6000 (Eve,Ivy), 7000 (Grace,Kate) */
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Assert( "3. Duplicate salaries: 4 distinct values", Rows( aR ) == 4 )
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RECOVER
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s_nTotal++ ; s_nFail++ ; ? " FAIL: 3. Duplicate salaries (exception)"
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END SEQUENCE
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RETURN
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/* ====================================================================
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* Challenge 4: Department vs Company Average (Analytics)
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* Compare each department's average salary to company average.
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* ==================================================================== */
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STATIC PROCEDURE Challenge04_DeptVsCompanyAvg()
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LOCAL aR
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dbCloseAll()
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BEGIN SEQUENCE
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aR := five_SQL( ;
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"WITH dept_avg AS (" + ;
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" SELECT dept, AVG(salary) AS dept_salary FROM employees GROUP BY dept" + ;
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"), company AS (" + ;
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" SELECT AVG(salary) AS company_salary FROM employees" + ;
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") SELECT d.dept, d.dept_salary, " + ;
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"CASE WHEN d.dept_salary > c.company_salary THEN 'Above' ELSE 'Below' END AS vs_avg " + ;
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"FROM dept_avg d, company c ORDER BY d.dept_salary DESC" )
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/* 4 departments compared to company average */
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Assert( "4. Dept vs Company avg: 4 depts", Rows( aR ) == 4 )
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RECOVER
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s_nTotal++ ; s_nFail++ ; ? " FAIL: 4. Dept vs Company avg (exception)"
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END SEQUENCE
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RETURN
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/* ====================================================================
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* Challenge 5: Employees earning more than their manager (LeetCode #181)
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* Self-join to compare employee salary with manager salary.
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* ==================================================================== */
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STATIC PROCEDURE Challenge05_EmployeeManagerSalary()
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LOCAL aR
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dbCloseAll()
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BEGIN SEQUENCE
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aR := five_SQL( ;
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"SELECT e.name AS employee, m.name AS manager, " + ;
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"e.salary AS emp_salary, m.salary AS mgr_salary " + ;
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"FROM employees e JOIN employees m ON e.mgr_id = m.id " + ;
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"WHERE e.salary > m.salary" )
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/* Leo(9000) > Bob(8000), Kate(7000) > Bob(8000)? No. Check: Leo mgr=Bob(8000), Leo=9000>8000 YES */
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Assert( "5. Employee > Manager salary", Rows( aR ) >= 1 )
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RECOVER
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s_nTotal++ ; s_nFail++ ; ? " FAIL: 5. Employee > Manager (exception)"
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END SEQUENCE
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RETURN
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/* ====================================================================
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* Challenge 6: Cumulative/Running Sum (Analytics)
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* Running total of salary within each department.
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* ==================================================================== */
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STATIC PROCEDURE Challenge06_CumulativeSum()
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LOCAL aR
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dbCloseAll()
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BEGIN SEQUENCE
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aR := five_SQL( ;
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"SELECT name, dept, salary, " + ;
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"SUM(salary) OVER (PARTITION BY dept ORDER BY salary) AS running_total " + ;
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"FROM employees ORDER BY dept, salary" )
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Assert( "6. Running SUM by dept: 12 rows", Rows( aR ) == 12 )
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RECOVER
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s_nTotal++ ; s_nFail++ ; ? " FAIL: 6. Running SUM (exception)"
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END SEQUENCE
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RETURN
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/* ====================================================================
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* Challenge 7: Gap Analysis — Find departments with no orders
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* LEFT JOIN + IS NULL pattern (anti-join).
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* ==================================================================== */
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STATIC PROCEDURE Challenge07_GapAnalysis()
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LOCAL aR
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dbCloseAll()
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BEGIN SEQUENCE
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aR := five_SQL( ;
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"SELECT DISTINCT e.dept FROM employees e " + ;
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"WHERE e.dept NOT IN (" + ;
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" SELECT DISTINCT e2.dept FROM employees e2 " + ;
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" JOIN orders o ON e2.id = o.emp_id" + ;
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")" )
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/* All depts have at least one employee with orders, so result may be 0 */
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Assert( "7. Depts without orders (anti-join)", Rows( aR ) >= 0 )
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RECOVER
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s_nTotal++ ; s_nFail++ ; ? " FAIL: 7. Gap analysis (exception)"
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END SEQUENCE
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RETURN
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/* ====================================================================
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* Challenge 8: Pivot Simulation with CASE
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* Count employees per department as columns using CASE aggregation.
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* ==================================================================== */
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STATIC PROCEDURE Challenge08_PivotSimulation()
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LOCAL aR
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dbCloseAll()
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BEGIN SEQUENCE
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aR := five_SQL( ;
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"SELECT " + ;
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"SUM(CASE WHEN dept = 'Eng' THEN 1 ELSE 0 END) AS eng, " + ;
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"SUM(CASE WHEN dept = 'Sales' THEN 1 ELSE 0 END) AS sales, " + ;
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"SUM(CASE WHEN dept = 'Mktg' THEN 1 ELSE 0 END) AS mktg, " + ;
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"SUM(CASE WHEN dept = 'HR' THEN 1 ELSE 0 END) AS hr " + ;
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"FROM employees" )
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/* Eng=5, Sales=3, Mktg=2, HR=2 */
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Assert( "8. Pivot CASE: Eng=5 Sales=3 Mktg=2 HR=2", ;
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Rows( aR ) == 1 .AND. Cell( aR, 1, 1 ) == 5 .AND. ;
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Cell( aR, 1, 2 ) == 3 .AND. Cell( aR, 1, 3 ) == 2 .AND. ;
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Cell( aR, 1, 4 ) == 2 )
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RECOVER
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s_nTotal++ ; s_nFail++ ; ? " FAIL: 8. Pivot CASE (exception)"
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END SEQUENCE
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RETURN
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/* ====================================================================
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* Challenge 9: Self-Join Hierarchy — Org tree with recursive CTE
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* Find all reports (direct and indirect) for each manager.
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* ==================================================================== */
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STATIC PROCEDURE Challenge09_SelfJoinHierarchy()
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LOCAL aR
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dbCloseAll()
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BEGIN SEQUENCE
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aR := five_SQL( ;
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"WITH RECURSIVE org AS (" + ;
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"SELECT id, name, mgr_id, 1 AS depth FROM employees WHERE mgr_id = 0 " + ;
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"UNION ALL " + ;
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"SELECT e.id, e.name, e.mgr_id, o.depth + 1 " + ;
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"FROM employees e JOIN org o ON e.mgr_id = o.id" + ;
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") SELECT name, depth FROM org ORDER BY depth, name" )
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Assert( "9. Org hierarchy: 12 employees, depth 1 first", ;
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Rows( aR ) == 12 .AND. Cell( aR, 1, 2 ) == 1 )
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RECOVER
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s_nTotal++ ; s_nFail++ ; ? " FAIL: 9. Org hierarchy (exception)"
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END SEQUENCE
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RETURN
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/* ====================================================================
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* Challenge 10: Top N Per Group — ROW_NUMBER filter
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* Highest earner per department (exactly 1 per dept).
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* ==================================================================== */
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STATIC PROCEDURE Challenge10_TopNPerGroup()
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LOCAL aR
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dbCloseAll()
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BEGIN SEQUENCE
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aR := five_SQL( ;
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"WITH ranked AS (" + ;
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"SELECT name, dept, salary, " + ;
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"ROW_NUMBER() OVER (PARTITION BY dept ORDER BY salary DESC) AS rn " + ;
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"FROM employees" + ;
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") SELECT name, dept, salary FROM ranked WHERE rn = 1 ORDER BY salary DESC" )
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/* 4 departments, 1 top earner each */
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Assert( "10. Top 1 per dept: 4 rows", Rows( aR ) == 4 )
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RECOVER
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s_nTotal++ ; s_nFail++ ; ? " FAIL: 10. Top N per group (exception)"
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END SEQUENCE
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RETURN
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/* ====================================================================
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* Challenge 11: Running Rank — LAG + comparison
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* Show each employee's salary and the difference from previous.
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* ==================================================================== */
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STATIC PROCEDURE Challenge11_RunningRank()
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LOCAL aR
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dbCloseAll()
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BEGIN SEQUENCE
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aR := five_SQL( ;
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"WITH lagged AS (" + ;
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"SELECT name, salary, " + ;
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"LAG(salary, 1) OVER (ORDER BY salary DESC) AS prev_sal " + ;
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"FROM employees" + ;
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") SELECT name, salary, prev_sal, " + ;
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"salary - COALESCE(prev_sal, salary) AS diff " + ;
|
|
"FROM lagged ORDER BY salary DESC" )
|
|
Assert( "11. LAG + diff via CTE: 12 rows", ;
|
|
Rows( aR ) == 12 )
|
|
RECOVER
|
|
s_nTotal++ ; s_nFail++ ; ? " FAIL: 11. LAG + diff (exception)"
|
|
END SEQUENCE
|
|
|
|
RETURN
|
|
|
|
|
|
/* ====================================================================
|
|
* Challenge 12: Year-over-Year Growth (Analytics)
|
|
* Compare 2023 vs 2022 order totals per employee.
|
|
* ==================================================================== */
|
|
STATIC PROCEDURE Challenge12_YoYGrowth()
|
|
|
|
LOCAL aR
|
|
|
|
dbCloseAll()
|
|
BEGIN SEQUENCE
|
|
aR := five_SQL( ;
|
|
"WITH y22 AS (" + ;
|
|
" SELECT emp_id, SUM(amount) AS total FROM orders WHERE ord_year = 2022 GROUP BY emp_id" + ;
|
|
"), y23 AS (" + ;
|
|
" SELECT emp_id, SUM(amount) AS total FROM orders WHERE ord_year = 2023 GROUP BY emp_id" + ;
|
|
") SELECT e.name, y22.total AS yr2022, y23.total AS yr2023 " + ;
|
|
"FROM employees e " + ;
|
|
"JOIN y22 ON e.id = y22.emp_id " + ;
|
|
"JOIN y23 ON e.id = y23.emp_id " + ;
|
|
"ORDER BY e.name" )
|
|
Assert( "12. YoY growth: employees with both years", Rows( aR ) >= 5 )
|
|
RECOVER
|
|
s_nTotal++ ; s_nFail++ ; ? " FAIL: 12. YoY growth (exception)"
|
|
END SEQUENCE
|
|
|
|
RETURN
|
|
|
|
|
|
/* ====================================================================
|
|
* Challenge 13: Island & Gap — Fibonacci via recursive CTE
|
|
* Generate Fibonacci numbers and find gaps.
|
|
* ==================================================================== */
|
|
STATIC PROCEDURE Challenge13_IslandGap()
|
|
|
|
LOCAL aR
|
|
|
|
dbCloseAll()
|
|
BEGIN SEQUENCE
|
|
aR := five_SQL( ;
|
|
"WITH RECURSIVE fib AS (" + ;
|
|
"SELECT 1 AS n, 1 AS val, 0 AS prev " + ;
|
|
"UNION ALL " + ;
|
|
"SELECT n + 1, val + prev, val FROM fib WHERE n < 12" + ;
|
|
") SELECT n, val FROM fib ORDER BY n" )
|
|
/* 12 Fibonacci numbers: 1,1,2,3,5,8,13,21,34,55,89,144 */
|
|
Assert( "13. Fibonacci 12 terms: fib(12)=144", ;
|
|
Rows( aR ) == 12 .AND. Cell( aR, 12, 2 ) == 144 )
|
|
RECOVER
|
|
s_nTotal++ ; s_nFail++ ; ? " FAIL: 13. Fibonacci (exception)"
|
|
END SEQUENCE
|
|
|
|
RETURN
|
|
|
|
|
|
/* ====================================================================
|
|
* Challenge 14: Median approximation using percentile position
|
|
* Find the middle salary using ROW_NUMBER and COUNT.
|
|
* ==================================================================== */
|
|
STATIC PROCEDURE Challenge14_MedianApprox()
|
|
|
|
LOCAL aR
|
|
|
|
dbCloseAll()
|
|
BEGIN SEQUENCE
|
|
aR := five_SQL( ;
|
|
"WITH numbered AS (" + ;
|
|
"SELECT salary, " + ;
|
|
"ROW_NUMBER() OVER (ORDER BY salary) AS rn, " + ;
|
|
"COUNT(*) OVER () AS total " + ;
|
|
"FROM employees" + ;
|
|
") SELECT salary FROM numbered " + ;
|
|
"WHERE rn = total / 2 + 1" )
|
|
/* 12 employees sorted by salary, median position = 7th */
|
|
Assert( "14. Median salary (position-based)", Rows( aR ) >= 1 )
|
|
RECOVER
|
|
s_nTotal++ ; s_nFail++ ; ? " FAIL: 14. Median approx (exception)"
|
|
END SEQUENCE
|
|
|
|
RETURN
|
|
|
|
|
|
/* ====================================================================
|
|
* Challenge 15: Triple nested subquery + CTE + Window
|
|
* Most complex: CTE -> Window -> Subquery filter -> JOIN -> ORDER BY
|
|
* ==================================================================== */
|
|
STATIC PROCEDURE Challenge15_TripleNested()
|
|
|
|
LOCAL aR
|
|
|
|
dbCloseAll()
|
|
BEGIN SEQUENCE
|
|
aR := five_SQL( ;
|
|
"WITH order_stats AS (" + ;
|
|
" SELECT emp_id, SUM(amount) AS total, COUNT(*) AS cnt " + ;
|
|
" FROM orders GROUP BY emp_id" + ;
|
|
") " + ;
|
|
"SELECT e.name, e.dept, e.salary, s.total, " + ;
|
|
"RANK() OVER (ORDER BY s.total DESC) AS order_rank " + ;
|
|
"FROM employees e " + ;
|
|
"JOIN order_stats s ON e.id = s.emp_id " + ;
|
|
"WHERE e.salary > (SELECT AVG(salary) FROM employees) " + ;
|
|
"ORDER BY s.total DESC" )
|
|
/* Employees with above-avg salary who also have orders, ranked by order total */
|
|
Assert( "15. CTE+Window+Subquery+JOIN: complex analytics", Rows( aR ) >= 1 )
|
|
RECOVER
|
|
s_nTotal++ ; s_nFail++ ; ? " FAIL: 15. Triple nested (exception)"
|
|
END SEQUENCE
|
|
|
|
RETURN
|