3

varchar在 mysql 表中有一个带有特殊字符的字段。我想使用 MYSQL QUERY 删除该字符串中的所有特殊字符。

4

4 回答 4

2

MySQL 不支持这样的查询。您在 MySQL 查询中的最佳选择是以下很多:

update TABLENAME
set FIELDNAME = replace(FIELDNAME,'_','')
于 2012-09-29T11:36:17.877 回答
2

您可以使用以下功能

DROP FUNCTION IF EXISTS `stripSpeciaChars`;
DELIMITER ;;
CREATE FUNCTION `stripSpeciaChars`(`dirty_string` varchar(2048),allow_space TINYINT,allow_number TINYINT,allow_alphabets TINYINT,no_trim TINYINT) RETURNS varchar(2048) CHARSET utf8
BEGIN
/**
 * MySQL function to remove Special characters, Non-ASCII,hidden characters leads to spaces, accents etc
 * Downloaded from http://DevZone.co.in
 * @param VARCHAR dirty_string : dirty string as input
 * @param VARCHAR allow_space : allow spaces between string in output; takes 0-1 as parameter
 * @param VARCHAR allow_number : allow numbers in output; takes 0-1 as parameter
 * @param VARCHAR allow_alphabets : allow alphabets in output; takes 0-1 as parameter
 * @param VARCHAR no_trim : don't trim the output; takes 0-1 as parameter
 * @return VARCHAR clean_string : clean string as output
 * 
 * Usage Syntax: stripSpeciaChars(string,allow_space,allow_number,allow_alphabets,no_trim);
 * Usage SQL> SELECT stripSpeciaChars("sdfa7987*&^&*ÂÃ ÄÅÆÇÈÉÊ sd sdfgËÌÍÎÏÑ ÒÓÔÕÖØÙÚàáâã sdkarkhru",0,0,1,0);
 * result : sdfasdsdfgsdkarkhru
 */
      DECLARE clean_string VARCHAR(2048) DEFAULT '';
      DECLARE c VARCHAR(2048) DEFAULT '';
      DECLARE counter INT DEFAULT 1;

      DECLARE has_space TINYINT DEFAULT 0; -- let spaces in result string
      DECLARE chk_cse TINYINT DEFAULT 0; 
      DECLARE adv_trim TINYINT DEFAULT 1; -- trim extra spaces along with hidden characters, new line characters etc.     

         if allow_number=0 and allow_alphabets=0 then
        RETURN NULL;
      elseif allow_number=1 and allow_alphabets=0 then
      set chk_cse =1;
     elseif allow_number=0 and allow_alphabets=1 then
      set chk_cse =2;
      end if;     

      if allow_space=1 then
      set has_space =1;
      end if;

       if no_trim=1 then
      set adv_trim =0;
      end if;

      IF ISNULL(dirty_string) THEN
            RETURN NULL;
      ELSE

      CASE chk_cse
      WHEN 1 THEN 
      -- return only Numbers in result
      WHILE counter <= LENGTH(dirty_string) DO

                  SET c = MID(dirty_string, counter, 1);

                  IF ASCII(c) = 32 OR ASCII(c) >= 48 AND ASCII(c) <= 57  THEN
                        SET clean_string = CONCAT(clean_string, c);
                  END IF;

                  SET counter = counter + 1;
            END WHILE;
      WHEN 2 THEN 
      -- return only Alphabets in result
      WHILE counter <= LENGTH(dirty_string) DO

                  SET c = MID(dirty_string, counter, 1);

                  IF ASCII(c) = 32 OR ASCII(c) >= 65 AND ASCII(c) <= 90  OR ASCII(c) >= 97 AND ASCII(c) <= 122 THEN
                        SET clean_string = CONCAT(clean_string, c);
                  END IF;

                  SET counter = counter + 1;
            END WHILE;
      ELSE
       -- return numbers and Alphabets in result
        WHILE counter <= LENGTH(dirty_string) DO

                  SET c = MID(dirty_string, counter, 1);

                  IF ASCII(c) = 32 OR ASCII(c) >= 48 AND ASCII(c) <= 57 OR ASCII(c) >= 65 AND ASCII(c) <= 90  OR ASCII(c) >= 97 AND ASCII(c) <= 122 THEN
                        SET clean_string = CONCAT(clean_string, c);
                  END IF;

                  SET counter = counter + 1;
            END WHILE;      
    END CASE;            
      END IF;


      -- remove spaces from result
      if has_space=0 then
      SET clean_string =REPLACE(clean_string,' ','');
      end if;

       -- remove extra spaces, newline,tabs. from result
     if adv_trim=1 then
      SET clean_string =TRIM(Replace(Replace(Replace(clean_string,'\t',''),'\n',''),'\r',''));
      end if;    

      RETURN clean_string;
END
;;
DELIMITER ;
SELECT stripSpeciaChars("foo79ÒÓÔÕÖØÙÚàáâã 87*&bÄÅÆÇÈÉÊar",1,0,1,1); -- result foo bar
于 2015-03-30T15:36:40.257 回答
1

采用

update table_name set field_name = REPLACE(field_name,'/','')
于 2012-09-29T11:31:19.907 回答
0

替换下面的字符

~ ! @ # $ % ^ & * ( ) _ +
` - = 
{ } |
[ ] \
: " 
; '

< > ?
, . 

用这个 SQL

SELECT note as note_original, 

    REPLACE(
        REPLACE(
            REPLACE(
                REPLACE(
                    REPLACE(
                        REPLACE(
                            REPLACE(
                                REPLACE(
                                    REPLACE(
                                        REPLACE(
                                            REPLACE(
                                                REPLACE(
                                                    REPLACE(
                                                        REPLACE(
                                                            REPLACE(
                                                                REPLACE(
                                                                    REPLACE(
                                                                        REPLACE(
                                                                            REPLACE(
                                                                                REPLACE(
                                                                                    REPLACE(
                                                                                        REPLACE(
                                                                                            REPLACE(
                                                                                                REPLACE(
                                                                                                    REPLACE(
                                                                                                        REPLACE(
                                                                                                            REPLACE(
                                                                                                                REPLACE(
                                                                                                                    REPLACE(
                                                                                                                        REPLACE(
                                                                                                                            REPLACE(
                                                                                                                                REPLACE(
                                                                                                                                    REPLACE(note, '"', ''),
                                                                                                                                '.', ''),
                                                                                                                            '?', ''),
                                                                                                                        '`', ''),
                                                                                                                    '<', ''),
                                                                                                                '=', ''),
                                                                                                            '{', ''),
                                                                                                        '}', ''),
                                                                                                    '[', ''),
                                                                                                ']', ''),
                                                                                            '|', ''),
                                                                                        '\'', ''),
                                                                                    ':', ''),
                                                                                ';', ''),
                                                                            '~', ''),
                                                                        '!', ''),
                                                                    '@', ''),
                                                                '#', ''),
                                                            '$', ''),
                                                        '%', ''),
                                                    '^', ''),
                                                '&', ''),
                                            '*', ''),
                                        '_', ''),
                                    '+', ''),
                                ',', ''),
                            '/', ''),
                        '(', ''),
                    ')', ''),
                '-', ''),
            '>', ''),
        ' ', '-'),
    '--', '-') as note_changed FROM invheader
于 2015-02-11T08:43:15.783 回答