LESSON 1 1 98 364 Database Administration Fundamentals
LESSON 1. 1 98 -364 Database Administration Fundamentals Understand How Data is Stored in Tables
LESSON 1. 1 98 -364 Database Administration Fundamentals Lesson Overview 1. 1 Understand how data is stored in tables. In this lesson, you will review: § Field § Column § Row § Record § Table § Variable
LESSON 1. 1 98 -364 Database Administration Fundamentals § Field A location in a record in which a particular type of data is stored. For example, EMPLOYEE-RECORD might contain fields to store Last-Name, First-Name, Address, City, State, Zip-Code, Hire-Date, Current-Salary, Title, Department, and so on. Individual fields are characterized by their maximum length and the type of data (for example, alphabetic, numeric, or financial) that can be placed in them. The facility for creating these specifications usually is contained in the data definition language (DDL). In a relational database management system (RDMS), fields are called columns. A field is one spot in a table. A field = data = some value
LESSON 1. 1 98 -364 Database Administration Fundamentals § Column In an RDMS, the name of an attribute. The collection of column values that form the description of a particular entity is called a tuple or row. A column is equivalent to a field in a record in a nonrelational file system. A column is a group of items that are listed up and down (that is, vertically).
LESSON 1. 1 98 -364 Database Administration Fundamentals § Row A series of items arranged horizontally within some type of framework—for example, a continuous series of cells running from left to right in a spreadsheet; a horizontal line of pixels on a video screen; or a set of data values aligned horizontally in a table. A row is a group of items that are listed across—left to right (that is, horizontally).
LESSON 1. 1 98 -364 Database Administration Fundamentals § Record A data structure that is a collection of fields (elements), each with its own name and type. A record is a group of fields across one row.
LESSON 1. 1 98 -364 Database Administration Fundamentals § Table In an RDMS, a data structure characterized by rows and columns, with data occupying or potentially occupying each cell formed by a row-column intersection. The table is the underlying structure of a relation. A table is a group of rows and columns.
LESSON 1. 1 98 -364 Database Administration Fundamentals § Variable A variable name is the label that we give to a column. Note: This is a slightly different definition from what you might have learned in a programming class. In programming, a variable is defined as a named storage location capable of containing data that can be modified during program execution.
LESSON 1. 1 98 -364 Database Administration Fundamentals Notes Review–Student Project
LESSON 1. 1 98 -364 Database Administration Fundamentals Assignment § Create a table/database that holds all the records of your report card.
- Slides: 10