There are 7 keys in DBMS<\/p>\n

<\/p>\n

Primary Key<\/strong><\/h3>\n

\n
• Key which is used to identify one and only instance of entity uniquely. An Enity can contains multiple keys, and keys which is most suitable becomes the primary key.<\/li>\n
• For each entity the primary key selection is based on requirements and developers.<\/li>\n<\/ul>\n

  <\/p>\n

  Candidate Key<\/strong><\/h3>\n

  \n
  • A key or an attribute that uniquely identifies a tuple is called Candidate key.<\/li>\n
  • Apart from primary key, other keys are considered as candiate key.<\/li>\n
  • The candidate keys are as strong as the primary key.<\/li>\n<\/ul>\n

    <\/p>\n

    Super Key<\/strong><\/h3>\n

    \n
    • An attribute set that can uniquely identify a tuple is called as Super Key. It is a superset of candidate key.<\/li>\n<\/ul>\n

      <\/p>\n

      Foreign Key<\/strong><\/h3>\n

      \n
      • Column of table that is used to point the primary key of another table is called as Foreign key.<\/li>\n<\/ul>\n

        <\/p>\n

        Alternate Key<\/strong><\/h3>\n

        \n
        • One of more attributes or a combination of attributes that uniquely identifies a tuples in a relation is called Alternate Key.<\/li>\n
        • These attributes or combinations of the attributes are called the candidate keys.<\/li>\n
        • One key is chosen as primary key and the other keys remain as candidate keys if they exist and is called as alternate keys.<\/li>\n
        • Total number of alternate keys is the total number of candidate keys minus the primary key.<\/li>\n
        • In a relation if there is only one candidate key alternate keys may or may not exist.<\/li>\n<\/ul>\n

          <\/p>\n

          Composite Key<\/strong><\/h3>\n

          \n
          • Whenever there is more than one attribute in a primary key, it is known as Composite key or concatenated key.<\/li>\n<\/ul>\n

            <\/p>\n

            Artificial Key<\/strong><\/h3>\n

            \n
            • Keys that are created using arbitarily assigned data is known as artificial keys.<\/li>\n
            • When primary key is large and complex and has no relationship with other relations, then the artificial key is created.<\/li>\n
            • Data values of an artificial key are usually numbered in serial order.<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"

              There are 7 keys in DBMS Primary Key Key which is used to identify one and only instance of entity uniquely. An Enity can contains multiple keys, and keys which is most suitable becomes the primary key. For each entity the primary key selection is based on requirements and developers. Candidate Key A key or […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"passster_activate_protection":false,"passster_protect_child_pages":"","passster_protection_type":"password","passster_password":"","passster_activate_overwrite_defaults":"","passster_headline":"","passster_instruction":"","passster_placeholder":"","passster_button":"","passster_id":"","passster_activate_misc_settings":"","passster_redirect_url":"","passster_hide":"no","passster_area_shortcode":"","gtb_hide_title":false,"gtb_wrap_title":false,"gtb_class_title":"","gtb_remove_headerfooter":false,"footnotes":""},"categories":[7157],"tags":[17548,17550,17540,17554,17544,17546,17553,17552,17547,17545,17549,17543,17539,17541,17551,17542,17555],"class_list":["post-4472","post","type-post","status-publish","format-standard","hentry","category-dbms","tag-candidate-key-in-dbms","tag-candidate-key-in-dbms-with-example","tag-dbms-keys","tag-describe-different-types-of-keys-in-dbms","tag-different-types-of-keys-in-dbms","tag-different-types-of-keys-in-dbms-with-examples","tag-discuss-different-types-of-keys-in-dbms-with-example","tag-explain-different-types-of-keys-in-dbms","tag-foreign-key-in-dbms","tag-primary-key-in-dbms","tag-super-key-in-dbms","tag-types-of-keys-in-database-management-system","tag-types-of-keys-in-dbms","tag-types-of-keys-in-relational-model","tag-unique-key-in-dbms","tag-various-types-of-keys-in-dbms","tag-what-are-keys-in-dbms-list-the-different-types-of-keys-in-dbms"],"yoast_head":"\n