如何使用两列转置表格

Question

我需要帮助来转置表格，但只使用一列并从另一列复制信息。

更新

我有这个问题：

CREATE SEQUENCE SEQ_document MINVALUE 1 MAXVALUE 9999999999999999999999999999 INCREMENT BY 1 START WITH 2206 NOCACHE  ORDER  NOCYCLE  NOKEEP  NOSCALE  GLOBAL;

CREATE TABLE ALL_DOCUMENT ( 
     ID NUMBER(19,0) DEFAULT SEQ_document.nextval  NOT NULL
    ,ART_DOC    VARCHAR2(256 CHAR)
    ,TYPE_DOC   VARCHAR2(256 BYTE)
    ,DATE_DOC   TIMESTAMP(6)
    ,VALUE_DOC  NUMBER(19,6)
    ,TABLENAME_DOC  VARCHAR2(256 BYTE)
);




INSERT INTO "MIBDES"."ALL_DOCUMENT" (ART_DOC, TYPE_DOC, DATE_DOC, VALUE_DOC, TABLENAME_DOC) VALUES ('A00', '35', TO_TIMESTAMP('2020-04-30 13:49:24.330761000', 'YYYY-MM-DD HH24:MI:SS.FF'), '9,7599', 'table_1');
INSERT INTO "MIBDES"."ALL_DOCUMENT" (ART_DOC, TYPE_DOC, DATE_DOC, VALUE_DOC, TABLENAME_DOC) VALUES ('A00', '75', TO_TIMESTAMP('2020-03-14 13:50:02.312782000', 'YYYY-MM-DD HH24:MI:SS.FF'), '13,6562', 'table_2');
INSERT INTO "MIBDES"."ALL_DOCUMENT" (ART_DOC, TYPE_DOC, DATE_DOC, VALUE_DOC, TABLENAME_DOC) VALUES ('A00', '35', TO_TIMESTAMP('2020-03-4 13:50:02.312782000', 'YYYY-MM-DD HH24:MI:SS.FF'), '6,9978', 'table_2');
INSERT INTO "MIBDES"."ALL_DOCUMENT" (ART_DOC, TYPE_DOC, DATE_DOC, VALUE_DOC, TABLENAME_DOC) VALUES ('A00', '16', TO_TIMESTAMP('2020-04-8 13:50:02.312782000', 'YYYY-MM-DD HH24:MI:SS.FF'), '4,7851', 'table_3');

commit;

想法或要求是这样的：

而且我不清楚如何进行此转置。有人可以帮帮我吗？

最好的问候

Answer 1

table_1 和 table_2 列是否在所有行中显示相同的值？

以下子查询使用CASE 表达式和MAX 函数可以获得一行。 然后您可以通过加入行和 ALL_DOCUMENT 表来获得预期的结果。

SELECT ART_DOC,TYPE_DOC,DATE_DOC,"table_1","table_2"
  FROM ALL_DOCUMENT CROSS JOIN
  (SELECT
    MAX(CASE WHEN TABLENAME_DOC='table_1' THEN VALUE_DOC END) AS "table_1",
    MAX(CASE WHEN TABLENAME_DOC='table_2' THEN VALUE_DOC END) AS "table_2"
   FROM ALL_DOCUMENT) T;

dbfiddle

Answer 2

如果您更新了问题，查询如下：

SELECT ART_DOC,TYPE_DOC,
  MAX(CASE WHEN TABLENAME_DOC='table_1' THEN VALUE_DOC END) AS "table_1",
  MAX(CASE WHEN TABLENAME_DOC='table_2' THEN VALUE_DOC END) AS "table_2",
  MAX(CASE WHEN TABLENAME_DOC='table_3' THEN VALUE_DOC END) AS "table_3"
FROM ALL_DOCUMENT
GROUP BY ART_DOC,TYPE_DOC
ORDER BY "table_1","table_2","table_3";

您可以使用GROUP BY 子句和MAX 函数和CASE 表达式获取每个TABLENAME_DOC 的VALUE_DOC。

dbfiddle

Answer 3

基本上有两种方法可以在 Oracle 的 SQL 中进行透视：

1. 使用条件聚合：

   虽然您可以将结果列旋转为

   SELECT art_doc, type_doc,
          MAX(CASE WHEN tablename_doc = 'table_1' THEN value_doc END) AS "table_1",
          MAX(CASE WHEN tablename_doc = 'table_2' THEN value_doc END) AS "table_2",
          MAX(CASE WHEN tablename_doc = 'table_3' THEN value_doc END) AS "table_3"
     FROM all_document 
    GROUP BY art_doc, type_doc;
   

   这是静态方法，你最好选择动态方法，通过创建一个SYS_REFCURSOR类型的函数返回值比如

   CREATE OR REPLACE FUNCTION Get_Pivoted_Documents RETURN SYS_REFCURSOR IS
     v_recordset SYS_REFCURSOR;
     v_sql       VARCHAR2(32767);
     v_cols      VARCHAR2(32767); 
   BEGIN
     SELECT LISTAGG( 'MAX(CASE WHEN tablename_doc = '''||tablename_doc||'''  THEN value_doc END) AS "'||tablename_doc||'"' , ',' )
             WITHIN GROUP ( ORDER BY TO_NUMBER( REGEXP_REPLACE(tablename_doc,'[^0-9]') ) )
       INTO v_cols
       FROM (
             SELECT DISTINCT tablename_doc
               FROM all_document
             );
   
     v_sql :=
     'SELECT art_doc , type_doc, '|| v_cols ||'
        FROM all_document
       GROUP BY art_doc , type_doc'; 
   
     OPEN v_recordset FOR v_sql;
     RETURN v_recordset;
   END;
   /
   

2. 使用 PIVOT 子句：

   使用静态方法 ;

   SELECT art_doc , type_doc, 
          MAX("table_1") AS "table_1",
          MAX("table_2") AS "table_2",
          MAX("table_3") AS "table_3"
     FROM all_document
    PIVOT 
    (
     MAX(value_doc) FOR tablename_doc IN ('table_1' AS "table_1",'table_2' AS "table_2",'table_3' AS "table_3")
    )
    GROUP BY art_doc , type_doc;
   

   使用动态方法：

   CREATE OR REPLACE FUNCTION Get_Pivoted_Documents RETURN SYS_REFCURSOR IS
     v_recordset SYS_REFCURSOR;
     v_sql       VARCHAR2(32767);
     v_cols_1    VARCHAR2(32767); 
     v_cols_2    VARCHAR2(32767);  
   BEGIN
     SELECT LISTAGG( 'MAX("'||tablename_doc||'") AS "'||tablename_doc||'"' , ',' )
             WITHIN GROUP ( ORDER BY TO_NUMBER( REGEXP_REPLACE(tablename_doc,'[^0-9]') ) )
       INTO v_cols_1
       FROM (
             SELECT DISTINCT tablename_doc
               FROM all_document
             );
   
     SELECT LISTAGG( ''''||tablename_doc||''' AS "'||tablename_doc||'"' , ',' )
             WITHIN GROUP ( ORDER BY TO_NUMBER( REGEXP_REPLACE(tablename_doc,'[^0-9]') ) )
       INTO v_cols_2
       FROM (
             SELECT DISTINCT tablename_doc
               FROM all_document
             );
   
     v_sql :=
     'SELECT art_doc , type_doc, '|| v_cols_1 ||'
        FROM all_document
       PIVOT 
       (
         MAX(value_doc) FOR tablename_doc IN ( '|| v_cols_2 ||' )
       )
        GROUP BY art_doc , type_doc'; 
   
     OPEN v_recordset FOR v_sql;
     RETURN v_recordset;
   END;
   /
   

然后从 SQL Developer 的控制台撤销

SQL> DECLARE
    result SYS_REFCURSOR;
BEGIN
   :result := Get_Pivoted_Documents;
END;
/

SQL> PRINT result ;

或来自PL/SQL Developer的测试窗口：

begin
  -- Call the function
  :result := get_pivoted_documents;  --> yields Value of type <Cursor>
end;