在开发过程中,很多时候并不知道有多上行转换为列,所以只有通过动态来进行转换。下面是我在工作中的一个简答例子(其实行转列的动态sql无非就是拼sql语句,然后通过游标的方式进行读取转换):
CREATE OR REPLACE PROCEDURE P_TEST_LIUHC(CYCLE_DATE IN VARCHAR2)
AUTHID CURRENT_USER
IS
V_SQL VARCHAR2(20000);
-- P_YW_ASSESS_ID NUMBER;
-- P_ASSESS_COLUMN VARCHAR2(30);
----------查找所使用到的指标ID
CURSOR CURSOR_1 IS
SELECT DISTINCT YW_ASSESS_ID,ASSESS_COLUMN
FROM RPT_KPI_YW_QD X, CS_ASSESS Y
WHERE X.YW_ASSESS_ID=Y.ASSESS_ID AND
STATEMENT_DATE = ''||CYCLE_DATE||'' AND
YW_ASSESS_ID IS NOT NULL AND YW_KPI_TYPE<>'计件考核宽表'
ORDER BY YW_ASSESS_ID,ASSESS_COLUMN;
BEGIN
---定义一个SQL前缀(以下采用拼凑SQL的方式逐级拼凑)
V_SQL := 'SELECT YW_KPI_TYPE,
YW_BSS_ORG_ID,
YW_BSS_ORG_NAME,
YW_CHANNEL_TYPE_ID';
-------开始循使用 (获取所有指标并分组)
--OPEN CURSOR_1;
--FETCH CURSOR_1 INTO P_YW_ASSESS_ID,P_ASSESS_COLUMN;
FOR V_XCLCK IN CURSOR_1
LOOP
V_SQL := V_SQL || ',' || 'SUM(DECODE(YW_ASSESS_ID,''' || V_XCLCK.YW_ASSESS_ID ||
''',AMOUNT,0)) AS ' || V_XCLCK.ASSESS_COLUMN;
END LOOP;
V_SQL := V_SQL || ' ,STATEMENT_DATE,REMARK '||' FROM RPT_KPI_YW_QD WHERE STATEMENT_DATE = '||CYCLE_DATE||'
GROUP BY YW_KPI_TYPE,
YW_BSS_ORG_ID,
YW_BSS_ORG_NAME,
YW_CHANNEL_TYPE_ID,
STATEMENT_DATE,
REMARK';
-- DBMS_OUTPUT.PUT_LINE(V_SQL);
-- EXECUTE IMMEDIATE 'DROP VIEW RESULT_LIUHC';
DROP_TEMP_TABLE('RESULT_LIUHC_1');
V_SQL := 'CREATE TABLE RESULT_LIUHC_1 AS '|| V_SQL;
--DBMS_OUTPUT.PUT_LINE(V_SQL);
EXECUTE IMMEDIATE V_SQL;
COMMIT;
END P_TEST_LIUHC;