ITEC 313 Database Programming

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ITEC 313 Database Programming. Bits of SQL. Objectives. Review Select Statement Creating tables Learn how to create and use Sequence View Learn how to Grant/Revoke priveleges. Syntax of SELECT. SELECT [ALL | DISTINCT] select-list FROM table-reference-list - PowerPoint PPT Presentation

Transcript of ITEC 313 Database Programming

Review › Select Statement› Creating tables

Learn how to create and use› Sequence› View

Learn how to Grant/Revoke priveleges

SELECT [ALL | DISTINCT] select-list FROM table-reference-list [WHERE search-condition] [GROUP BY column-name [, column-name]... ] [HAVING search-condition] [[UNION | UNION ALL |INTERSECT | MINUS] select-statement ]... [ORDER BY {unsigned integer | column-name} [ASC|DESC]]

select-list :› columns, expressions, fixed values.› Include aliases

table-reference-list› Tables, views, subqueries (inline view)

search-condition› Conditions involving columns, fixed values,

subqueries

CREATE TABLE table-name(Column-name data-type

[column-constraints] [DEFAULT default-value]

{, Column-name data-type [column-constraints] [DEFAULT default-value]

}[table-constraint {, table-constraint}])

ALTER TABLE table-nameADD column-declaration [ column-

constraints]OrALTER TABLE table-nameADD table-constraintsOrALTER TABLE table nameMODIFY column

autonumber field › independent of a column

An object in Oracle that is used to generate a number sequence

Useful for creating a unique number to act as a primary key

CREATE SEQUENCE sequence_name    MINVALUE value    MAXVALUE value    START WITH value    INCREMENT BY value    CACHE value;

Representation of an sql statement› Only the code to create the view is stored

in the data dictionary NOT the actual data Used for

› Improving efficiency› Improving Security› Hiding details/columns from end users

CREATE VIEW view-nameASSelect-statement

Privileges are of two types :›  SYSTEM PRIVILEGES › OBJECT PRIVILEGES

GRANT : allows users access to your objects.› INSERT, DELETE, UPDATE, SELECT, EXECUTE

privileges may be granted to other users REVOKE : removes existing privileges on

an object from other users.

GRANT INSERT, DELETE, UPDATE, SELECT, EXECUTE|ALL on object-name TO user-list|ROLE|PUBLIC;

REVOKE INSERT, DELETE, UPDATE, SELECT, EXECUTE | ALL on object-name FROM user-list|ROLE|PUBLIC;

ROLE: contaimns groups of users determined by the DBA

PUBLIC : A system ROLE that contains all users of the database