If I have a MyISAM table with Dynamic as row format, are the numeric columns (int(11), bigint(12)..) dynamic or static columns?
For example, if I have int(11) as the column type but the maximum value for this column is 1234, in this case does this column use only the space required which is int(4) or does it use the space like int(11)?
For dynamic row format in MyISAM every column is dynamic: http://dev.mysql.com/doc/refman/5.7/en/dynamic-format.html
int(4) and int(11) both take 4 bytes
The length just specifies how many characters to display when selecting data with the mysql command line client.