I have two tables, seemigly very similar setup; the primary key is the
combination of two columns. With mysqldump, however, the table
definition of the two tables looks different.
Mysqldump on table 1 says
UNIQUE KEY HONstid (HONstid,HONname)
whereas on table 2 it says
PRIMARY KEY (IMstid,IMfnum)
What is the difference? Is there any?
mysql> desc table1;
| HONstid | int(3) | | PRI | 1 | |
| HONname | char(20) | | PRI | standard | |
mysql> desc table2;
| IMstid | int(3) | | PRI | 0 | |
| IMfnum | int(6) | | PRI | 0 | |
A general question: is there a difference between a "primary key" and a
"unique key", or they are synonims?