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CREATE TABLE table1
(`title` varchar(18))
INSERT INTO table1
(`title`)
VALUES
('14 blue5 sky'),
('3 5gold sun"'),
('''/lorem ip25sum'),
('light moon'),
(' čć đš hello')
SELECT REGEXP_REPLACE(
REGEXP_REPLACE(
REGEXP_REPLACE(title, '[^[:alpha:] ]', ''),
'^\\s+', ''),
'\\s+', ' ') AS newtitle FROM table1
| newtitle |
|---|
| blue sky |
| gold sun |
| lorem ipsum |
| light moon |
| čć đš hello |
UPDATE table1
SET title = REGEXP_REPLACE(
REGEXP_REPLACE(
REGEXP_REPLACE(title, '[^[:alpha:] ]', ''),
'^ ', ''),
'\\s+', ' ')
SELECT * FROM table1
| title |
|---|
| blue sky |
| gold sun |
| lorem ipsum |
| light moon |
| čć đš hello |