如何使用两列转置表格

问题描述

我需要帮助来转置表格，但仅使用一个列并从另一列复制信息。

更新

我有这个查询：

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,'75',TO_TIMESTAMP('2020-03-14 13:50:02.312782000','13,6562','table_2');
INSERT INTO "MIBDES"."ALL_DOCUMENT" (ART_DOC,TO_TIMESTAMP('2020-03-4 13:50:02.312782000','6,9978','16',TO_TIMESTAMP('2020-04-8 13:50:02.312782000','4,7851','table_3');

commit;

想法或要求是这样的：

https://twigfiddle.com/zhm9bh

我不知道如何进行移调。有人可以帮我吗？

最好的问候

解决方法

列table_1和 table_2在所有行中都显示相同的值吗？

以下使用CASE表达式和MAX函数的子查询可以得到一行。 然后，通过将行和ALL_DOCUMENT表连接起来，可以得到预期的结果。

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

,

如果您有更新的问题，查询如下：

SELECT ART_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子句和带有MAX表达式的CASE函数来获取每个TABLENAME_DOC的VALUE_DOC。

dbfiddle

,

基本上，有两种方法可以在Oracle的SQL中进行数据透视：

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，您最好通过创建返回类型为SYS_REFCURSOR的函数（例如

   ）来选择动态方法

   CREATE OR REPLACE FUNCTION Get_Pivoted_Documents RETURN SYS_REFCURSOR IS
     v_recordset SYS_REFCURSOR;
     v_sql       VARCHAR2(32767);
     v_cols      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,'|| 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 条款：

   使用静态方法;

   SELECT art_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;
   

   采用动态方法：

   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||'"','[^0-9]') ) )
       INTO v_cols_1
       FROM (
             SELECT DISTINCT tablename_doc
               FROM all_document
             );
   
     SELECT LISTAGG( ''''||tablename_doc||''' AS "'||tablename_doc||'"','[^0-9]') ) )
       INTO v_cols_2
       FROM (
             SELECT DISTINCT tablename_doc
               FROM all_document
             );
   
     v_sql :=
     'SELECT art_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 的控制台撤消为

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;