我只想有字符（根本没有符号、数字和空格）

Question

应该用 SQLite 来完成

就这样；

是的，我知道，这很容易，如果我使用 UDF（用户定义函数）。

但是，我很难做到。

所以，寻找另一种方式（无 UDF 方式）来实现我的目标。

谢谢

供大家参考，

我留下了一个 link 我未能制作 UDF（使用 AutoHotkey）

SQLite/AutoHotkey, I have problem with Encoding of sqlite3_result_text return function

Answer 1

我相信你可以根据以下决议：-

WITH RECURSIVE eachchar(counter,rowid,c,rest) AS (
        SELECT 1,rowid,'',mycolumn AS rest FROM mytable
        UNION ALL 
            SELECT counter+1,rowid,substr(rest,1,1),substr(rest,2) FROM eachchar WHERE length(rest) > 0 LIMIT 100
    )
SELECT group_concat(c,'') AS mycolumn, myothercolumn, mycolumn AS original
FROM eachchar JOIN mytable ON eachchar.rowid = mytable.rowid 
WHERE length(c) > 0 
    AND (
        unicode(c) BETWEEN unicode('a') AND unicode('z') 
        OR unicode(c) BETWEEN unicode('A') AND unicode('Z')
    )
GROUP BY rowid;

演示：-

也许考虑以下：-

/* Create the Test Environment */
DROP TABLE IF EXISTS mytable;
CREATE TABLE IF NOT EXISTS mytable (mycolumn TEXT, myothercolumn);
/* Add the Testing data */
INSERT INTO mytable VALUES
    ('123-abc_"D E F()[]{}~`!@#$%^&*-+=|\?><<:;''','A')
    ,('123-xyz_"X Y Z()[]{}~`!@#$%^&*-+=|\?><<:;''','B')
    ,('123-abc_"A B C()[]{}~`!@#$%^&*-+=|\?><<:;''','C')
;

/* split each character thenconcatenat only the required characters*/
WITH RECURSIVE eachchar(counter,rowid,c,rest) AS (
        SELECT 1,rowid,'',mycolumn AS rest FROM mytable
        UNION ALL 
            SELECT counter+1,rowid,substr(rest,1,1),substr(rest,2) FROM eachchar WHERE length(rest) > 0 LIMIT 100
    )
SELECT group_concat(c,'') AS mycolumn, myothercolumn, mycolumn AS original
FROM eachchar JOIN mytable ON eachchar.rowid = mytable.rowid 
WHERE length(c) > 0 
    AND (
        unicode(c) BETWEEN unicode('a') AND unicode('z') 
        OR unicode(c) BETWEEN unicode('A') AND unicode('Z')
    )
GROUP BY rowid;
/* Cleanup Test Environment */
DROP TABLE IF EXISTS mytable;

这导致：-

我只想有字符（根本没有符号、数字和空格）

I'd like to have Characters only (no signs, numbers and spaces at all)

sqlite

autohotkey

演示：-