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HomeDatabaseMysql TutorialMySql判断汉字、日期、数字的具体函数_MySQL

几个平常用的mysql函数,MySql判断汉字、日期、数字的具体函数分享给大家,具体内容如下

1.判断字符串是否为汉字 返回值:1-汉字 0-非汉字


DROP FUNCTION IF EXISTS fc_is_hanzi;

CREATE FUNCTION fc_is_hanzi(
p_str VARCHAR(1024)
)
  RETURNS int(11)
  NOT DETERMINISTIC
  SQL SECURITY DEFINER
  COMMENT '检查字符串是否为汉字'
BEGIN
/*检查字符串是否为汉字 返回值:1-汉字 0-非汉字*/

  DECLARE _ret, i, other_cnt, l_acode INT DEFAULT 0;
  SET _ret = 0;
  SET i = 1;
  SET other_cnt = 0;
  SET l_acode = 0;
  WHILE i <= CHAR_LENGTH(p_str) DO
    SET l_acode = ASCII(SUBSTRING(p_str, i, 1));
    IF l_acode254 THEN
      SET other_cnt = other_cnt + 1;
    END IF;
    SET i = i + 1;
  END WHILE;
  IF other_cnt = 0 THEN
    SET _ret = 1;
  ELSE
    SET _ret = 0;
  END IF;
  RETURN _ret;
END;


2.判断日期格式是否正确(返回值:1-正确 0-错误)


DROP FUNCTION IF EXISTS fc_ck_date;

CREATE FUNCTION fc_ck_date(
p_cont CHAR(32) 
)
  RETURNS tinyint(4)
  NOT DETERMINISTIC
  SQL SECURITY DEFINER
  COMMENT &#39;判定日期格式是否正确&#39;
BEGIN
/*判定日期格式是否正确(返回值:1-正确 0-错误)*/
/*输入值格式为:yyyyMMdd 或 yyyy-MM-dd*/

IF(SELECT DATE_FORMAT(p_cont,&#39;%Y%m%d&#39;)) IS NULL THEN
  RETURN 0;
ELSE
  RETURN 1;
END IF;

END;


3.判断字符串是否为纯数字(返回值:1-为纯数字 0-非纯数字)


DROP FUNCTION IF EXISTS fc_is_num;

CREATE FUNCTION fc_is_num(
p_string VARCHAR(32) 
)
  RETURNS int(4)
  NOT DETERMINISTIC
  SQL SECURITY DEFINER
  COMMENT &#39;检查字符串是否为纯数字&#39;
BEGIN
/*检查字符串是否为纯数字*/
/*返回值:1-为纯数字 0-非纯数字*/

   DECLARE iResult INT DEFAULT 0;
   SELECT p_string REGEXP &#39;^[0-9]*$&#39; INTO iResult;
   IF iResult = 1 THEN
    RETURN 1;
   ELSE
     RETURN 0;
   END IF;
END;


以上就是MySql判断汉字、日期、数字的三段函数,希望对大家的学习有所帮助,更多相关内容请关注PHP中文网(www.php.cn)!


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