Database Systems Chapter 7

SQL (Structured Query Language)

Used to create and manipulate databases

Aggregate Functions (DML)

Used with SELECT to return mathematical summaries on columns

ALTER TABLE (DDL)

add columns, delete columns, add constraints; Modifies a table's definition

CREATE TABLE (DDL)

Creates a new table in the user's database schema

DELETE (DML)

Deletes one or more rows from a table

INSERT (DML)

Inserts row(s) into table

DISTINCT (DML)

Limits values to unique values

UPDATE (DML)

Modifies an attribute's values in one or more table's rows

DROP TABLE (DDL)

Permanently deletes a table (and its data)

HAVING (DML)

Restricts the selection of grouped rows based on a condition

SELECT (DML)

Selects attributes from rows in one or more tables or views

CREATE DATABASE

The SQL command to create a database

DDL (Data Definition Language)

allow you to define the structure; Consists of the SQL commands that can be used to define the database schema. It simply deals with descriptions of the database schema and is used to create and modify the structure of database objects in database.

DML (Data Manipulation Language)

allow you to manipulate the contain of the data; The SQL commands that deals with the manipulation of data present in database

GROUP BY (DML)

allow you to receive and arrange your data set; groups the selected rows based on one or more attributes

SQL Statements

create database/table; add, modify, delete data; retrieve, join data

COMMIT (DML)

the end of a program is successfully reached

ORDER BY (DML)

to sort data; Orders the selected rows based on one or more attributes

ROLLBACK (DML)

transaction management commands; restores data to its original values

View

will create a virtual table