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create table mytable (val varchar(50));
insert into mytable values
('12345.0'),
('A119B'),
('65489.0'),
('BD585'),
('123.0'),
('124.0'),
('12.0');
SELECT * FROM mytable;
| val |
|---|
| 12345.0 |
| A119B |
| 65489.0 |
| BD585 |
| 123.0 |
| 124.0 |
| 12.0 |
SELECT SUBSTRING_INDEX(val,'.',1) FROM mytable;
| SUBSTRING_INDEX(val,'.',1) |
|---|
| 12345 |
| A119B |
| 65489 |
| BD585 |
| 123 |
| 124 |
| 12 |
UPDATE mytable SET val=SUBSTRING_INDEX(val,'.',1) WHERE val LIKE '%.%';
SELECT * FROM mytable;
| val |
|---|
| 12345 |
| A119B |
| 65489 |
| BD585 |
| 123 |
| 124 |
| 12 |