MySQL LTRIM() function

LTRIM() function

MySQL LTRIM() removes the leading space characters of a string passed as an argument.

This function is useful in -

• Leading character removal: LTRIM() removes certain characters from the left side of a string.
• Data cleaning: LTRIM() is often used to remove spaces from strings at the beginning.

Syntax:

LTRIM(str)

Argument:

Syntax Diagram:

MySQL Version: 8.0

Example of MySQL LTRIM() function

The following MySQL statement returns the string ‘ Hello’ after removing the leading space characters. In the output, the first column shows the string with leading space characters and the second column shows the string after performing LTRIM.

Code:

SELECT ' Hello', LTRIM(' Hello');

Output:

mysql> SELECT ' Hello', LTRIM(' Hello');
+---------+------------------+
| Hello  | LTRIM(' Hello') |
+---------+------------------+
|  Hello | Hello           | 
+---------+------------------+
1 row in set (0.02 sec)

Example of LTRIM() with update statement

The following MySQL statement will update the aut_name column for all the rows by removing the leading space characters (if any).

Code:

UPDATE author SET aut_name=LTRIM(aut_name);

Sample table: author

Output:

mysql> UPDATE author SET aut_name=LTRIM(aut_name);
Query OK, 0 rows affected (0.09 sec)
Rows matched: 15  Changed: 0  Warnings: 0

Example of LTRIM() with update statement using WHERE clause

The following MySQL statement will update the aut_name column by removing the leading space characters for those rows which don't belong to the ' USA'.

Code:

UPDATE author SET aut_name=LTRIM(aut_name)
WHERE country<>'USA';

Sample table: author

Output:

mysql> UPDATE author SET aut_name=LTRIM(aut_name)
    -> WHERE country<>'USA';
Query OK, 0 rows affected (0.01 sec)
Rows matched: 11  Changed: 0  Warnings: 0

Video Presentation

All String Functions (Slides presentation)

Previous: LPAD
Next: MAKE_SET