oracle汉字转拼音 获得全拼/拼音首字母/拼音截取等
小例子一枚：

CREATE OR REPLACE FUNCTION "F_SPELLCN" (P1 VARCHAR2,P2 INT default 0) return VARCHAR2 as
    /*
     * 获得汉字拼音首字母
     * 入口参数：汉字字符串、是否只取第一个汉字的拼音首字母
     */  
       CHAR1 VARCHAR2(2);
       CHAR2 VARCHAR2(2);
       LEN INTEGER;
       N1 INTEGER;
       N2 INTEGER;
       CSOUND VARCHAR2(32767);
  
   BEGIN
      if p1 is null then
        return '';
      end if;
       IF P2 = 1 THEN
           LEN := 1;
       ELSE
           LEN := LENGTH(P1);
       END IF;
       if LEN=0 then
        return '';
      end if;
      
       FOR I IN 1..LEN LOOP
           CHAR2 := SUBSTR(P1, i, 1);
           N1 := FLOOR(ASCII(CHAR2) / 256);
           N2 := MOD(ASCII(CHAR2), 256);
          
           IF N1 = 0 AND N2 <= 129 THEN
               CHAR1 := CHAR2;
           ELSIF N2 <> 127 AND N2 <> 255 AND NOT (N2 >= 0 AND N2 <= 63) THEN
               SELECT
                   CASE
                      WHEN CHAR2 >= '丂' AND CHAR2 < '芭' THEN 'A'
               　     WHEN CHAR2 >= '芭' AND CHAR2 < '擦' THEN 'B'
                      WHEN CHAR2 >= '擦' AND CHAR2 < '搭' THEN 'C'
                      WHEN CHAR2 >= '搭' AND CHAR2 < '蛾' THEN 'D'
                      WHEN CHAR2 >= '蛾' AND CHAR2 < '发' THEN 'E'
                      WHEN CHAR2 >= '发' AND CHAR2 < '噶' THEN 'F'
                      WHEN CHAR2 >= '噶' AND CHAR2 < '哈' THEN 'G'
                      WHEN CHAR2 >= '哈' AND CHAR2 < '击' THEN 'H'
                      WHEN CHAR2 >= '击' AND CHAR2 < '喀' THEN 'J'
                      WHEN CHAR2 >= '喀' AND CHAR2 < '垃' THEN 'K'
                      WHEN CHAR2 >= '垃' AND CHAR2 < '妈' THEN 'L'
                      WHEN CHAR2 >= '妈' AND CHAR2 < '拿' THEN 'M'
                      WHEN CHAR2 >= '拿' AND CHAR2 < '哦' THEN 'N'
                      WHEN CHAR2 >= '哦' AND CHAR2 < '啪' THEN 'O'
                      WHEN CHAR2 >= '啪' AND CHAR2 < '期' THEN 'P'
                      WHEN CHAR2 >= '期' AND CHAR2 < '然' THEN 'Q'
                      WHEN CHAR2 >= '然' AND CHAR2 < '撒' THEN 'R'
                      WHEN CHAR2 >= '撒' AND CHAR2 < '塌' THEN 'S'
                      WHEN CHAR2 >= '塌' AND CHAR2 < '挖' THEN 'T'
                      WHEN CHAR2 >= '挖' AND CHAR2 < '稀' THEN 'W'
                      WHEN CHAR2 >= '稀' AND CHAR2 < '压' THEN 'X'
                      WHEN CHAR2 >= '压' AND CHAR2 < '匝' THEN 'Y'
                      WHEN CHAR2 >= '匝' AND CHAR2 <= '鼱' THEN 'Z'
                   END
                   INTO CHAR1
               FROM DUAL;
           ELSE
               CHAR1 := 'ER';
           END IF;
          
           CSOUND := CSOUND || CHAR1;
       END LOOP;
      
       RETURN CSOUND;
   END;