Mysql ORDER BY varchar列存储为数字

Question

I have a mysql column (staffid) which format is varchar(11). This column is used to store staff id, which are generally 1,2,3............40,60... I can't use int format for that column as for contractual staff it stores id as cont-1, while for regular staff it stores id as integer 1,2,3... While I am trying to fetch array using a ORDER BY clause with that column, rows are not fetching with correct order. My sql query is:

SELECT * FROM database ORDER BY CAST('staffid' as UNSIGNED INTEGER) ASC

How can I format that varchar column in mysql query so that for regular staff it treats as integer column as order by that column?

Answer 1

the proper syntax is,

SELECT  * 
FROM    `database` 
ORDER   BY CAST(staffid AS UNSIGNED) ASC

since you have mentioned that there are some ids with this format cont-1 . probably you can add WHERE clause to filter specific ID,

SELECT  * 
FROM    `database`
WHERE   staffid NOT LIKE 'cont%' 
ORDER   BY CAST(staffid AS UNSIGNED) ASC