mysql alter table generate_imagesmodify image_type varchar64 not null comment 图片下载类型psdaijpgpngpptgif;ERROR 1064 42000 You have an error in your SQL syntax; check the manual that corresponds to your M

The correct syntax for the ALTER TABLE statement in MySQL is:

ALTER TABLE table_name MODIFY column_name column_definition;

In your case, the correct syntax would be:

mysql> ALTER TABLE generate_images MODIFY image_type varchar(64) not null comment '图片下载类型:psd,ai,jpg,png,ppt,gif';