LEFT()
Description
This function LEFT()
returns the leftmost len characters from the string str, or NULL if any argument is NULL.
This function is multibyte safe.
Syntax
> LEFT(str,len)
Arguments
Arguments | Description |
---|---|
str | Required. The string to extract from. |
len | Required. The number of characters to extract. If this parameter is larger than the number of characters in string, this function will return string |
Examples
mysql> select left('abcde', 3) from dual;
+----------------+
| left(abcde, 3) |
+----------------+
| abc |
+----------------+
1 row in set (0.00 sec)
drop table if exists t1;
CREATE TABLE t1 (str VARCHAR(100) NOT NULL, len INT);
insert into t1 values('abcdefghijklmn',3);
insert into t1 values(' ABCDEFGH123456', 3);
insert into t1 values('ABCDEF GHIJKLMN', 20);
insert into t1 values('ABCDEFGHijklmn ', -1);
insert into t1 values('ABCDEFGH123456', -35627164);
insert into t1 values('', 3);
mysql> select left(str, len) from t1;
+------------------+
| left(str, len) |
+------------------+
| abc |
| A |
| ABCDEF GHIJKLMN |
| |
| |
| |
+------------------+
6 rows in set (0.01 sec)
mysql> select left('sdfsdfsdfsdf', len) from t1;
+-------------------------+
| left(sdfsdfsdfsdf, len) |
+-------------------------+
| sdf |
| sdf |
| sdfsdfsdfsdf |
| |
| |
| sdf |
+-------------------------+
6 rows in set (0.01 sec)