oracle split去逗号,行列转换

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1.针对  '1','2','3','4','5'(逗号在字符串外面)

SQL> SELECT COLUMN_VALUE  FROM TABLE(SYS.ODCIVARCHAR2LIST('1','2','3','4','5'));COLUMN_VALUE--------------------------------------------------------------------------------12345

2.针对'1,2,3,4,5'(逗号在字符串里面)

SQL> select regexp_substr('1,2,3,4,5','[^,]+',1,rownum) from dual  2  connect by rownum<=length('1,2,3,4,5')-length(replace('1,2,3,4,5',','))+1  3  ;REGEXP_SUBSTR('1,2,3,4,5','[^,------------------------------12345

3.使用函数

CREATE OR REPLACE TYPE ty_str_split IS TABLE OF VARCHAR2 (4000);

CREATE OR REPLACE FUNCTION fn_split (p_str IN CLOB, p_delimiter IN VARCHAR2) RETURN ty_str_splitIS  j INT := 0;  i INT := 1;  len INT := 0;  len1 INT := 0;  str VARCHAR2 (4000);  str_split ty_str_split := ty_str_split ();BEGIN  len := LENGTH (p_str);  len1 := LENGTH (p_delimiter);  WHILE j < len  LOOP    j := INSTR (p_str, p_delimiter, i);    IF j = 0    THEN        j := len;        str := SUBSTR (p_str, i);        str_split.EXTEND;        str_split (str_split.COUNT) := str;        IF i >= len        THEN          EXIT;        END IF;    ELSE        str := SUBSTR (p_str, i, j - i);        i := j + len1;        str_split.EXTEND;        str_split (str_split.COUNT) := str;    END IF;  END LOOP;  RETURN str_split;END fn_split;

测试:
SQL> select * from table(fn_split('1,2,3,4,5',','));    --第二个单引号中是前面字符串中需要被分隔的字符COLUMN_VALUE--------------------------------------------------------------------------------12345SQL> select * from table(fn_split('1,2,3,4。5','。'));COLUMN_VALUE--------------------------------------------------------------------------------1,2,3,45

参考:

http://www.itpub.net/thread-1346178-1-1.html

众大牛们已经总结了行列转换的若干方法。今天发现了一种新的方法( ),和大家分享下。
1.SYS.ODCIVARCHAR2LIST:
SELECT COLUMN_VALUE  FROM TABLE(SYS.ODCIVARCHAR2LIST('1','2','3','4','5'));COLUMN_VALUE--------------------------------------------------------------------------------12345

Oracle 10G 以上版本才支持SYS.ODCIVARCHAR2LIST,其实SYS.ODCIVARCHAR2LIST只不过是一个TYPE,
所以在9I版本中可以通过创建一个TYPE来使用该功能:
CREATE OR REPLACE TYPE MY_ODCIVARCHAR2LIST AS VARRAY(32767) OF VARCHAR2(4000);

SELECT COLUMN_VALUE  FROM TABLE(MY_ODCIVARCHAR2LIST('1','2','3','4','5'));COLUMN_VALUE--------------------------------------------------------------------------------12345

但是,当'1','2','3','4','5'  作为一个字符串('1,2,3,4,5')就没有办法转换了:
SELECT COLUMN_VALUE  FROM TABLE(MY_ODCIVARCHAR2LIST('1,2,3,4,5'));COLUMN_VALUE--------------------------------------------------------------------------------1,2,3,4,5

总结:(1)Table函数将数组里的内容通过SQL语句查询出来;
          (2)ODCIVARCHAR2LIST 在9I 及以上版本中均可使用。在9I中可通过创建TYPE,10G及以上直接使用SYS.ODCIVARCHAR2LIST;
          (3)ODCIVARCHAR2LIST 适用于字符集,不适用单个字符串,如果是单个字符串,可以通过参考2中(如下)方法实现。

欢迎大家讨论,提出更多更好的方法~~

参考----------------------------------------------------------------
2.其他方法实现列转行(大牛们早已经总结,仅供参考)
(1) 利用CONNECT BY (使用9I,10G,11G)
WITH T AS (SELECT  '1,2,3,4,5' AS STR FROM DUAL)SELECT  STR1  FROM ( SELECT  DISTINCT                 SUBSTR(T.CA,INSTR(T.CA, ',', 1, C.LV) + 1,                       INSTR(T.CA, ',', 1, C.LV + 1) -(INSTR(T.CA, ',', 1, C.LV) + 1)) AS STR1       FROM (SELECT ',' || STR || ',' AS CA,LENGTH(STR || ',') -NVL(LENGTH(REPLACE(STR, ',')), 0) AS CNT FROM T) T,            (SELECT LEVEL LV FROM DUAL CONNECT BY LEVEL <= 9) C       WHERE C.LV <= T.CNT        ORDER BY STR1);

(2).正则表达式(使用10G及以上版本)
WITH TEST AS (SELECT  '1,2,3,4,5' AS STR FROM DUAL)SELECT DISTINCT REGEXP_SUBSTR(STR, '[^,]+', 1, LEVEL)FROM TESTCONNECT BY ROWNUM <= 5;


转载自:http://blog.csdn.net/wanglilin/article/details/7231712

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