达梦数据库字符串切割-自定义函数

--根据分隔符返回分隔的组数

CREATE OR REPLACE
FUNCTION get_StrArrayLength(STR VARCHAR(2000),SPLIT1 VARCHAR(10))
RETURN INT
AS
V_LOCATION INT;
V_START    INT;
V_LENGTH   INT;
BEGIN
STR:=LTRIM(RTRIM(STR));
V_LOCATION :=LOCATE(SPLIT1,STR);
V_LENGTH  :=1;
WHILE V_LOCATION <>0
LOOP
V_START:=V_LOCATION+1;
V_LOCATION   :=LOCATE(SPLIT1,STR,V_START);
V_LENGTH  :=V_LENGTH+1;
END LOOP;
RETURN V_LENGTH;
END;

--取出根据某个字符切割后的第n个字符串

CREATE OR REPLACE
FUNCTION get_StrArrayStrOfIndex(STR VARCHAR(2000),SPLIT1 VARCHAR(10),
INDEX1   INT)
RETURN VARCHAR(2000)
AS
V_LOCATION INT;
V_START    INT;
V_NEXT     INT;
V_SEED     INT;
BEGIN
STR:=LTRIM(RTRIM(STR));
V_START    :=1;
V_NEXT :=1;
V_SEED :=LEN(SPLIT1);
V_LOCATION :=LOCATE(SPLIT1,STR);
WHILE V_LOCATION  <>0 AND INDEX1 >V_NEXT
LOOP
V_START:=V_LOCATION+V_SEED;
V_LOCATION :=LOCATE(SPLIT1,STR,V_START);
V_NEXT :=V_NEXT+1;
END LOOP;
IF V_LOCATION=0 THEN
V_LOCATION :=LEN(STR)+1;
END IF;
RETURN SUBSTRING(STR,V_START,V_LOCATION-V_START);
END;

--调用方法

SELECT get_StrArrayLength('8a,9c,4c,5K',',') FROM SYSDBA.SYSDUAL ;

SELECT get_StrArrayStrOfIndex('8a,9c,4c,5K',',',3) FROM SYSDBA.SYSDUAL;