Oracle的字符串转数组以及数组转字符串

字符串转数组：  
  
(SELECT REGEXP_SUBSTR('34,56,-23', '[^,]+', 1, LEVEL, 'i') AS STR    
FROM DUAL    
CONNECT BY LEVEL <=    
 LENGTH('34,56,-23') - LENGTH(REGEXP_REPLACE('34,56,-23', ',', '')) + 1)  
   
  
数组转字符串  
 select wmsys.wm_concat(cityname) from sys_city  
 where provinceid='29'
字符串转数组：  
  
(SELECT REGEXP_SUBSTR('34,56,-