• Create BookmarkCreate Bookmark
  • Create Note or TagCreate Note or Tag
  • PrintPrint

Setting the Primary Key

Almost every table should have at least one field that has a unique value for each record. For instance, in a table of the dogs your kennel owns, you might assign an ID number to each dog, and have an ID # field in your table. Or you might choose to use each dog's AKC (American Kennel Club) registration number. This unique identifier field is known as the primary key field. If the table is to be the "one" side of a one-too-many relationship, it is required to have a primary key. Otherwise, it is optional (but usually advisable).

Note

Primary Key Field The designated field for which every record must have a unique entry. This is usually an ID number because most other fields could conceivably be the same for more than one record (for instance, two people might have the same first name).



PREVIEW

                                                                          

Not a subscriber?

Start A Free Trial


  
  • Creative Edge
  • Create BookmarkCreate Bookmark
  • Create Note or TagCreate Note or Tag
  • PrintPrint