Change
	
Change column definition
	
	Drop 
	
Remove the column from the table.
	
(action will be confirmed) 
	
	Primary
	
Set the column as the primary key for the table.
	
	Please note that if you need a primary key consisting of two or more columns, you will need to specify it when 
	creating the table in MySQLMan.  If there is a primary key already existed in the table, then you will receive the 
	error message Duplicate key name 'key_name'.  
	
	Also, if you set a column as the primary by clicking "primary", the column will be set to NOT NULL automatically.
	
	Index 
	
Set the column as a index key for the table.
	
	Unique 
	
Set the column as a unique key for the table.