A Key is a data item that exclusively identifies a record. In other words, key is a set of column(s) that is used to uniquely identify the record in a table. It is used to fetch or retrieve records / data-rows from data table according to the condition/requirement. Key provide several types of constraints like column can’t store duplicate values or null values. Keys are also used to generate relationship among different database tables or views.
Types of Keys Super Key Minim
Car-opening tool you're most likely to have on you at any given time is a shoestring. Unfortunately, this method only works on locking mechanisms that unlock by pulling up. You'll need to tie a small loop in the middle of the shoelace that can be tightened, then work the string into the door, pull the loop tight around the lock, and pull it up. It may take more than once if you are not a pro but it should work nonetheless. Unlock your car