char_length({str})

Returns the number of characters in a given string.

Example 

This example returns the number of characters in the first five entries in the City column.

1SELECT City, CHAR_LENGTH(City) as "CityLen"
2FROM "Superstore"
3GROUP BY City
4LIMIT 5;
CityCityLen
Aberdeen8
Abilene7
Akron5
Albuquerque11
Alexandria10