1.3.2

• what is the primary key?

  A primary key is a unique identifier for each record in a database table.
• what is the secondary key?

  A secondary key is an alternate key used to uniquely identify records in a database table.
• what is a composite primary key?

  primary key that consists of more than one attribute
• what is a foreign key?

  refers to the primary key of another table, establishing a relationship between the two tables.
• what is A in ACID?

  Atomicity - transaction is either completed entirely or not at all
• what does C stand for in ACID?

  Consistency - no transaction can violate the defined rules of validation
• what does I stand for in ACID?

  Isolation - each transaction does not interfere with another
• what does D stand for in ACID?

  Durability - once transaction is completed changes are saved and wont be lost
• what is a flat file database?

  consists of a single file one entity
• what is referential integrity?

  this ensures that a particular component isnt deleted if it is required somewhere else in a linked database
• what is a relational database?

  separate table created for each entity identified in the system
• what is the process of capturing data?

  data that is being inputted

  manually

  magnetic ink character recognition
• what is the process of exchanging data?

  EDI - electronic data interchange

  data transfer from one computer to another
• what is 1st normal form?

  no repeating attributes allowed

  all field names must be unique

  needs primary key
• what is 2nd normal form?

  Eliminating partial dependencies.

  no composite key
• what is 3rd normal form?

  Eliminating transitive dependencies.

  no non key dependency
• how to fix M:M relationship?

  add additional table and link through M:one and one:M