official website: MySQL:: MySQL 5.5 Reference Manual:: C.10.4 Limits on Table Column Count and Row Size: https://dev.mysql.com/doc/ref.

MySQL has hard limit of 4096 columns per table, but the effective maximum may be less for a given table. The exact column limit depends on several factors:

also, if you consider the limit of the number of columns, you should think about whether there is something wrong with the design