CREATE OR REPLACE FUNCTION f_back_str(in_str IN VARCHAR2) RETURN VARCHAR2 IS v_back_str VARCHAR2(500); v_mid_str VARCHAR2(20); v_count NUMBER(10); BEGIN v_count:=length(in_str); IF v_count<20 THEN FOR i IN 1..v_count LOOP v_back_str:=substr(in_str,i,1) || v_back_str; END LOOP; ELSE v_back_str:=in_str; END IF; RETURN v_back_str; END f_back_str; /SQL> SELECT f_back_str('csdn程序员论坛') FROM dual;F_BACK_STR('CSDN程序员论坛') -------------------------------------------------------------------------------- 坛论员序程ndsc
RETURN VARCHAR2
IS
v_back_str VARCHAR2(500);
v_mid_str VARCHAR2(20);
v_count NUMBER(10);
BEGIN
v_count:=length(in_str);
IF v_count<20 THEN
FOR i IN 1..v_count LOOP
v_back_str:=substr(in_str,i,1) || v_back_str;
END LOOP;
ELSE
v_back_str:=in_str;
END IF;
RETURN v_back_str;
END f_back_str;
/SQL> SELECT f_back_str('csdn程序员论坛') FROM dual;F_BACK_STR('CSDN程序员论坛')
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坛论员序程ndsc