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konvertera sql-tabellen i matrisform

Detta kan vara till hjälp för dig. Jag har använt CASE WHEN THEN END block för att uppnå PIVOT .

SELECT USERS.USER_NAME
  , MAX(COALESCE(TEST.USER1, 0)) USER1
  , MAX(COALESCE(TEST.USER2, 0)) USER2
  , MAX(COALESCE(TEST.USER3, 0)) USER3
  , MAX(COALESCE(TEST.USER7, 0)) USER7
FROM (
  SELECT DISTINCT USER_NAME 
  FROM (
      SELECT USER_NAME FROM TEST
      UNION ALL
      SELECT M_USER FROM TEST
    )
  ) USERS
    LEFT OUTER JOIN (
      SELECT
          USER_NAME
          , M_USER
          , CASE WHEN M_USER = 'user 1' THEN TOTAL ELSE 0 END AS USER1
          , CASE WHEN M_USER = 'user 2' THEN TOTAL ELSE 0 END AS USER2
          , CASE WHEN M_USER = 'user 3' THEN TOTAL ELSE 0 END AS USER3
          , CASE WHEN M_USER = 'user 7' THEN TOTAL ELSE 0 END AS USER7
      FROM TEST
    ) TEST ON USERS.USER_NAME = TEST.USER_NAME
GROUP BY USERS.USER_NAME
ORDER BY USERS.USER_NAME

UPPDATERA

Jag kunde inte hitta ett sätt att skriva detta i en enda fråga. Efter lite analys hittade jag detta .

CREATE OR REPLACE FUNCTION GETUSERS RETURN SYS_REFCURSOR AS
  QUERY VARCHAR2(32767);
  RC SYS_REFCURSOR;
BEGIN

  QUERY := 'SELECT USERS.USER_NAME ';

  FOR TMP IN (SELECT DISTINCT UPPER(REPLACE(USER_NAME, ' ', '')) USER_NAME FROM (SELECT USER_NAME FROM TEST UNION ALL SELECT M_USER FROM TEST) ORDER BY USER_NAME)
  LOOP
    QUERY := QUERY || '  , MAX(COALESCE(TEST.' || TMP.USER_NAME || ' , 0)) ' || TMP.USER_NAME;
  END LOOP;

  QUERY := QUERY || ' FROM ( ';
  QUERY := QUERY || '  SELECT DISTINCT USER_NAME ';
  QUERY := QUERY || '  FROM ( ';
  QUERY := QUERY || '      SELECT USER_NAME FROM TEST ';
  QUERY := QUERY || '      UNION ALL ';
  QUERY := QUERY || '      SELECT M_USER FROM TEST ';
  QUERY := QUERY || '    ) ';
  QUERY := QUERY || '  ) USERS ';
  QUERY := QUERY || '    LEFT OUTER JOIN ( ';

  QUERY := QUERY || ' SELECT USER_NAME';
  FOR TMP IN (SELECT DISTINCT USER_NAME, REPLACE(USER_NAME, ' ', '') USER_COL_NM FROM (SELECT USER_NAME FROM TEST UNION ALL SELECT M_USER FROM TEST))
  LOOP
    QUERY := QUERY || ', CASE WHEN M_USER = ''' || TMP.USER_NAME
      || ''' THEN TOTAL ELSE 0 END AS ' || TMP.USER_COL_NM ;
  END LOOP;
  QUERY := QUERY || ' FROM TEST';

  QUERY := QUERY || '    ) TEST ON USERS.USER_NAME = TEST.USER_NAME ';
  QUERY := QUERY || 'GROUP BY USERS.USER_NAME ';
  QUERY := QUERY || 'ORDER BY USERS.USER_NAME';

  OPEN RC FOR QUERY;

  RETURN RC;
END;
/

Skapad funktion som dynamiskt skapar SQL och returnerar SYS_REFCURSOR . Detta kan köras i SQL*Plus eller SQL Developer (med 'kör som ett skript'),

VAR RC REFCURSOR;
EXEC :RC := GETUSERS;
PRINT RC



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