What is key and types of key?

A key refers to an attribute/a set of attributes that help us identify a row (or tuple) uniquely in a table (or relation). A key is also used when we want to establish relationships between the different columns and tables of a relational database. There are five main types of keys: sunk, saddle, tangent, round, and spline . Types of sunk keys: rectangular, square, parallel sunk, gib-head, feather, and Woodruff . Parallel keys are the most widely used. They have a square or rectangular cross-section.

What are keys?

A key is a field, or combination of fields, in a database table used to retrieve and sort rows in the table based on certain requirements. Keys are defined to speed up access to data and, in many cases, to create links between different tables.

What are the two types of keys?

Types of KeysSkeleton Key. Also known as a passkey, a skeleton key is a simple key with a cylindrical shaft and a single toothed end, which is used to open warded locks. ... Abloy Key. The Abloy key is used on disc tumbler locks. ... Dimple Key. ... Paracentric Key. ... Tubular Key. ... Keycard.

What is key types of key in SQL?

Different Types of SQL KeysSuper Key. A super key is a set of one or more than one key that can be used to identify a record uniquely in a table. ... Candidate Key. ... Primary Key. ... Alternate key. ... Composite/Compound Key. ... Unique Key. ... Foreign Key.

What are the different types of key files?

1. Software License Key File 2. LightWave License File 3. Security Key 4. Apple Keynote Presentation 5. Keyboard Definition File 6. Privacy-Enhanced Mail Private Key What is a KEY file? A KEY file is a generic file extension used by various programs when registering legal copies of the software.

What are the different keys on a keyboard?

These keys include the equal (=), divide (/), times (*), subtract (-), plus (+), period (.), numbers 0 through 9, and the Enter key. AFK, Alt, Ctrl, Delete, Enter, Hardware terms, Home row keys, Keyboard terms, Natural keyboard, Numeric keypad, OSK, Shift, Spacebar, Tab, Typewriter, Virtual keyboard, Windows key.

What are the different types of keys in cryptography?

Keys are typically designed to be both random and reasonably long such that they are difficult to guess. The following are common types of cryptographic key. A matching public/private key pair whereby anyone can encrypt with the public key but only those who hold the private key can decrypt. The public key in a asymmetric key pair.

What does key stand for?

Technology Key (engineering), a type of coupling used to transmit rotation between a shaft and an attached item KeY, a software verification tool .key, file extension used by Keynote Telegraph key, the button used by a telegraph operator