(intro) Every
organization has some information needs. A library keeps alist of members,
books,
due dates, and fines.
A company needs to save information about employees, departments,
and salaries. These
pieces of information are called data.
Organizations can
store data on various media and in different formats, such as a hard-copy
document in a filing
cabinet or data stored in electronic spreadsheets or in databases.
A database is an
organized collection of information.
To manage databases,
you need a database management system (DBMS). A DBMS is a
program that stores,
retrieves, and modifies data in databases on request. There are four
main types of
databases: hierarchical, network, relational, and (most recently) object
relational.
Oracle 10g features:
1- automatic database
diagnostic monitor
2- segment space
management
3- automatic SQL
execution memory
4- automatic storage
manager
5- automatic undo
managment
6- automatic workload
repository
7- change-aware
incremental backup
8- locally managed
tablespaces
9- SQL access advisor
10- SQL tuning
advisor.
Es men programming
nai hoti. Database design hota hai. Accounting n banking ka b database he
design hota hai. Lyk costumer name credit record,info etc save krne k lye. Aur
ap ye kam krne k liye query likhte hen. Jise ye bacha programming keh rha hai.
Query1: ye select
query ka syntax hai. Basic SELECT Statement
• SELECT identifies
the columns to be displayed
• FROM identifies the
table containing those columns
SELECT *|{[DISTINCT]
column|expression [alias],...}
FROM table;
Query 2: In the
syntax:
SELECT is a list of
one or more columns
* selects all columns
DISTINCT suppresses
duplicates
column??expression selects
the named column or the expression
alias gives selected
columns different headings
FROM table specifies
the table containing the columns..
---EnD---
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