|
|
3NF ==>
database normalisation
<database> A series of steps followed to obtain a database
design that allows for efficient access and storage of data
in a relational database. These steps reduce data
redundancy and the chances of data becoming inconsistent.
A table in a relational database is said to be in normal
form if it satisfies certain constraints. Codd's original
work defined three such forms but there are now five generally
accepted steps of normalisation. The output of the first step
is called First Normal Form (1NF), the output of the second
step is Second Normal Form (2NF), etc.
First Normal Form eliminates repeating groups by putting
each into a separate table and connecting them with a
one-to-many relationship.
Second Normal Form eliminates functional dependencies on a
partial key by putting the fields in a separate table from
those that are dependent on the whole key.
Third Normal Form eliminates functional dependencies on
non-key fields by putting them in a separate table. At this
stage, all non-key fields are dependent on the key, the whole
key and nothing but the key.
Fourth Normal Form separates independent multi-valued facts
stored in one table into separate tables.
Fifth Normal Form breaks out data redundancy that is not
covered by any of the previous normal forms.
http://www.bkent.net/Doc/simple5.htm.
[What about non-relational databases?]
(2004-05-19)
Try this search on OneLook / Google
Nearby terms:
database machine « database management system « database manager « database normalisation » database query language » database server » Data/BASIC
This article was derived from the Free Online Dictionary of Computers and is available under ther terms of the GNU Free Documentation License.
Dell Axim X5 400MHz Pocket PC w/64MB RAMDell Axim X5 400MHz Pocket PC w/64MB RAM ** Dell Axim X5 PDA with 400MHz Processor **The Dell Axim X5 is the ultimate handheld device that offers outstanding features at an affordable price. It's powered by the Intel XScale Processor running at 400MHz to help keep up with the tasks of everyday life, and also includes 64MB SDRAM and 48MB Intel StrataFlash ROM. The Axim X5 is equipped with Microsoft Pocket PC 2002 and comes pre-installed with familiar applications like Pocket Word and Pocket Excel, along with a calendar, contacts, voice recorder and a number of other built-in features. With an integrated Type II CompactFlash card slot and Secure Digital/MMC card slot, the expansion capabilities seem almost endless. ** Act today and we will throw in at NO EXTRA CHARGE a great looking Belkin executive zippered leather case, a top quality Dell foldable keyboard and Belkin USB rapid sync charger! **Axim Features:- Intel XScale 400MHz processor- 64MB RAM- 48MB FlashROM- Stylus stores in side of unit- Microsoft Pocket PC 2002 OS- 240x320 3.5-inch 16-bit color touch sensitive transflective LCD- Integrated AC '97 Audio codec- Integrated microphone and speaker- Stereo headphone jack- 1440 mAh rechargeable batteryControls:- Navigation button- Scroll Dial - Up, Down, Action- 4 Program Buttons: Calendar, Contacts, Inbox, Home- Voice Record Button- Reset Button- Backlit Power ButtonExpansion Slots:- One (1) CompactFlash Type IICard Slot (3.3v)- One (1) Secure Digital/MMC Card Slot (3.3V)Software:- Microsoft Pocket PC 2002- Calculator- Calendar- Contacts- Inbox- Internet Explorer- Pocket Excel- Pocket Word- Windows Media PlayerFactory Plain Box Includes:- Dell Axim X5 PDA with 400MHz Processor- USB cradle- AC Adapter (100-240VAC 50/60Hz) w/ power cord- Battery- CR2032 Lithium Battery- Carrying Case- User's GuideNote: - Companion CD not included*** FREE WITH PURCHASE ***- Dell Axim X5 PDA Foldable Keyboard for Pocket PC- Belkin USB Sync Charger- Belkin Executive Zippered Leather Case****************************FREE ACCESSORIES SPECS:Dell Axim X5 PDA Foldable Keyboard for Pocket PC Features:- Model: 0x379- Compact design- Fold-up keyboard- Built in cradle and standBelkin USB Sync Charger Features:- Model: F8D1000- Rapid data synchronization between your PDA and PC (without the cradle)- Can also charge your PDA from a powered USB port or in a car(w/included adapter)- Offers a mobile, lightweight design- perfect for travelersBelkin Executive Zippered Leather Case Features:- Offers fine-grain leather construction and precision crafting- Secures your Dell Axim X5 handheld with zippered closure- Holds 4 business or credit cards- 4.25 x 1.25 x 6.25 (WxDxH)- Black color- Note: Case has an embossed logo Compatibility/Requirements/Disclosures:** Requirements *** Windows PC running Windows 98SE or later* Available USB port* Available power outlet (to charge battery) More ...
Encarta Encyclopedia Deluxe 2003Encarta Encyclopedia Deluxe 2003 Encarta Encyclopedia Deluxe 2003 provides a wealth of up-to-date information for home, work, or school. Instant Access to Dynamic Information. Everything you need at your fingertips for a rich and reliable research experience. Windows 98/ME/2000/XP More ...
4MB 72 Pin 1x32 Non-Parity SIMM Module4MB 72 Pin 1x32 Non-Parity SIMM Module ** 4MB 72 Pin 1x32 Non-Parity SIMM Module **General Features:- 1 x 32- Non-parity- 72 pin- Tin or gold leadsCompatibility/Requirements/Disclosures:** Disclosures *** Picture is for representational purposes only More ...
PCI 2 Serial Port/1 Parallel Port I/O CardPCI 2 Serial Port/1 Parallel Port I/O Card ** PCI I/O Card - 2 Serial, 1 Parallel Port **If your computer did not come with parallel or serial ports,or you need more of such ports, take a look at this card!It features a PCI Plug & Play interface for compatibilitywith a wide variety of modern PCs (NOT Mac compatible.)Once installed, it provides two standard 9-pin serial ports,and one 25-pin parallel port. If this is what you need,act now, before they are all gone!General Features:- PCI interface- Provides two (2) standard 9-pin serial ports- Provides one (1) standard 25-pin parallel port- NetMOS NM9835CV chipset- Compatible with DOS, Windows 95/98/ME/2000/XP/NT 4.0Retail Package Includes:- PCI I/O Card w/2 serial, 1 parallel port- Brief installation guide- Driver CD Compatibility/Requirements/Disclosures: ** Requirements *** PC with available PCI slot* DOS or Windows 95/98/ME/2000/XP/NT 4.0 More ...http://www.softwaredealz.com/surplus/453359595.htmlSunday, 12 June 2005 19:09:11 -0600
17-Inch SVA TFT Flat Panel LCD Monitor w/Spk (Sil)17-Inch SVA TFT Flat Panel LCD Monitor w/Spk (Sil) ** SVA VR-17S 17-Inch TFT Flat Panel Color LCD Monitor **The SVA VR-17S17-inch LCD display combines outstanding screen images and multimedia performance in a stylish package! It features a 1280 x 1024 @ 75 Hz maximum resolution, built-in speakers and easy to use On Screen Display controls. In addition to a high 400:1 contrast ratio and 250 cd/m2 of brightness, it features a fast 45 ms response time for superior picture quality. Get yours today!General Features:- Silver case- 17-inch TFT LCD Screen- .264 mm dot pitch- 1280 x 1024 @ 75 Hz maximum resolution- 400:1 contrast ratio- 250 cd/m2 brightness- 45 ms response time- Built-in speakers- 150-degree horizontal viewing angle- 140-degree vertical viewing angle- On-Screen Display (OSD) controls- Audio in- 15-pin standard VGA connectorPower Specifications:- 100-240V, 50/60Hz, 12V, 4ARegulatory Approvals:- FCC- ULRetail Package Includes:- SVA VR-17S 17-Inch TFT Flat Panel Color LCD Monitor- Operating Instructions- VGA cable- Audio cable- AC adapter (100-240V, 50/60Hz, 1.2A)Notes:- LCD displays may have cosmetic imperfections that appear as small bright or dark spots. This is common to all LCD displays used in products by all vendors and is not specific to any one vendor or brand. Below are the acceptable amounts of dot defects for LCD displays that we sell:- 17-Inch to 18-Inch:- Total Defects: 8- Bright or Dark Dots (random): 4- Bright or Dark Dots (2 adjacent): 2- Bright or Dark Dots (3 adjacent): 0- Minimum distance between defects: 15mm (bright to bright dots)- Minimum distance between defects: 5mm (dark to dark dots) Compatibility/Requirements/Disclosures:** Requirements *** VGA adapter* Audio source with 3.5 mm stereo mini-jack output* Available power outlet** Disclosures *** LCD displays may have cosmetic imperfections that appear as small bright or dark spots. This is common to all LCD displays used in products by all vendors and is not specific to any one vendor or brand. Below are the acceptable amounts of dot defects for LCD displays that we sell:* 17-Inch to 18-Inch:* Total Defects: 8* Bright or Dark Dots (random): 4* Bright or Dark Dots (2 adjacent): 2* Bright or Dark Dots (3 adjacent): 0* Minimum distance between defects: 15mm (bright to bright dots)* Minimum distance between defects: 5mm (dark to dark dots) Informational Links:http://www.sva-usa.comhttp://www.sva-usa.com/001/productitem.php?id=18&display=spec&img= More ...
McAfee Internet Security Suite 7.0 OEMMcAfee Internet Security Suite 7.0 OEM ** McAfee Internet Security Suite 7.0 OEM **IMPROVED! McAfee VirusScan- Automatically protects your PC, email, attachments, downloads and network from viruses, mass-mailing worms and backdoor Trojans whenever you go online. Fast anti-virus updates ensure your protection stays current. Now with more efficient email scanning of larger files. IMPROVED! McAfee Personal Firewall Plus- Helps block hackers, identity thieves and malicious code from robbing personal data, hijacking your system (often to send spam) or planting malicious code that can compromise your privacy over dial-up, DSL or cable connections. Now with enhanced intrusion detection and fast set-up assistant. IMPROVED! McAfee SpamKiller- Automatically recognizes and helps stop junk email-including credit card phishing scams, virus hoaxes and foreign language spam-from polluting your inbox. Regular anti-spam filter updates ensure the latest protection against spammers. Now with enhanced spam detection technology, Personal Filter Editor and Whitelisting. IMPROVED! McAfee Privacy Service- Helps shield individual family members from offensive content (e.g., websites, newsgroups), online stalkers and inappropriate chat, thanks to age-specific Parental Controls and easy-to-use filtering options. Identity Protection- Helps secure personal identification and financial information (e.g., name, phone, credit card, bank account numbers) from accidental transmission over the Internet without your permission. IMPROVED! Spyware/Adware Detection and Removal- Helps catch and delete potentially unwanted programs (PUPs) hiding on your PC that can steal log-ins and passwords (key-loggers), hijack your dial-up connection (Web dialers) or track your online surfing (adware). Pop-Up Blocking- Helps eliminate annoying Web advertising that not only slows your surfing but also tracks your browsing habits for advertisers. McAfee Shredder- Securely erases confidential files, folders and email for increased privacy and protection from desktop thieves.Notes:- Picture is for represenatational purposes only- OEM CD ONLY More ...
|
