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Title Placeholder Complement Union for Data Integration Jens Bleiholder #1, Sascha Szott +2, Melanie Herschel ∗3, Felix Naumann #4 #Hasso-Plattner-Institut, Universitat¨ Potsdam, Germany 1;4fjens.bleiholder | [email protected] +Konrad-Zuse-Zentrum fur¨ Informationstechnik Berlin, Germany [email protected] ∗Universitat¨ Tubingen,¨ Germany [email protected] Abstract— A data integration process consists of mapping each tuple from the sources is padded with nulls in the result source data into a target representation (schema mapping [1]), of outer union. That is, tuple 1 becomes (Miller, 7/7/59, m, identifying multiple representations of the same real-word object 12 Main, ?) and tuple 5 becomes (Miller, 7/7/59, m, ?, O). (duplicate detection [2]), and finally combining these represen- tations into a single consistent representation (data fusion [3]). These tuples have same values for Name, DOB, and Sex. Clearly, as multiple representations of an object are generally not Tuple 1 contributes Address whereas tuple 5 contributes Blood exactly equal, during data fusion, we have to take special care in to the final tuple during complementation. handling data conflicts. This paper focuses on the definition and Now, consider tuples 1 and 4. Assume that according to implementation of complement union, an operator that defines a duplicate detection, they represent the same real-world object, new semantics for data fusion. i.e., the same person. They both store different non-null values I. INTRODUCTION for Sex. Complement union cannot solve this type of conflict, Complement union aims at resolving a special type of data for which specialized methods exist (see [3] for a survey on conflict, called uncertainty. Intuitively, the operator considers fusion methods). cases where a concrete value in one tuple conflicts with a To the best of our knowledge, this work is the first that NULL value (?) of another tuple, and replaces the NULL considers data fusion with the general semantics of comple- value with the NON-NULL value when merging the tuples. ment union. A known operator that is able to combine comp- Complement union combines tuple sets by first computing lementing tuples from two sources is the full disjunction [4]. the outer union and then combining tuples that complement However, it cannot combine complementing tuples from the each other. This modular specification gives us more flexibility same source, nor can it combine tuples where overlapping/join attributes contain NULL values. during integration; complement can also be used to clean Amazon.com: Tu Vas Pas Mourir De Rire: Mickey 3D: Music 10/2/09 11:06 AM source databases before the integration process and it allows Real-world applications. In our experience with real-world Amazon.com: Tu Vas Pas Mourir De Rire: Mickey 3d: Music 10/2/09 11:09 AM us to potentially use more sophisticated schema mapping data, we observeHello. theSign in to usefulnessget personalized recommendations of complementation.. New customer? Start here. Kindle: Amazon's For Wireless Reading Device instance, in a sampleYour Amazon.com of the | InternetToday's Deals Movie | Gifts & Wish Database Lists | Gift Cards (IMDB) 1, Your Account | Help algorithms than the outer union. Hello. Sign in to get personalized recommendations. New customer? Start here. Kindle: Amazon's Wireless Reading Device Shop All Departments Search Music Cart Wish List we observe that complementation occurs withYour a Amazon.com frequency | Today's Deals | Gifts & Wish Lists | Gift Cards Your Account | Help Example. Consider a disaster management scenario. We in- Music Advanced Search Browse Genres New Releases Bestsellers Music Deals Music You Should Hear Music Essentials MP3 Downloads Shop All Departments Search Music Cart Wish List tegrate two databases Police and Hospital (excerpts shown in of up to 20 times higher than subsumption, the state-of-the Tu Vas Pas MourirMusic De Rire [IMPORT]Advanced Search Browse Genres New Releases Bestsellers Music Deals Music You Should Hear Music Essentials MP3 Downloads Get it for less! Mickey 3D (Artist) art data fusion operator to handle uncertainty. Also, we find Fig. 1 (a) and (b)). Note that tid is not a relational attribute but No customer reviews yet. Be the first. | More about this product Tu Vas PasHave Mourir one to sell? De Rire [IMPORT] Quantity: 1 serves as a reference to tuples. The goal is to detect missing numerous examples on the web, e.g., Fig. 2 shows excerptsMickey 3d (Artist) of This item has been discontinued by the manufacturer.No customer reviews yet. Be the first. | More about this product two complementing descriptions of the same CD. persons that have been admitted to a hospital and to contact List Price: $35.99 or Share with Friends Sign in to turn on 1-Click ordering. As complementation combines information that wasPrice: $35.99 not & ships FREE with Super Saver Shipping or their relatives when an address is available. or FREE Two-Day Shipping with a free trial of Amazon Fig. 1 (c) shows the result of applying complement union to already combined in one of the sources, we obtain a morePrime. Details Amazon.com: Tu Vas Pas Mourir De Rire: Mickey 3D: Music 10/2/09 11:05 AM Special Offers Available Amazon.com: Tu Vas Pas Mourir De Rire: Mickey 3d: Music 10/2/09 11:08 AM complete description of an object, albeit at the risk of cre- Amazon Prime Free Trial the two sources. Complement union is the result of applying required. Sign up when you Temporarily out of stock. Hello. Sign in to get personalized recommendations. New customer? Start here. Kindle: Amazon's Wireless Reading Device check out. Learn More Customers Viewing This Page May Be InterestedHello. in SignThese in to get Sponsoredpersonalized recommendations LinksOrder. New now (What's customer? and this?we'll Start) deliver here. whenKindle: available. Amazon's We'llWireless e-mail Reading you Device with an Your Amazon.com Today's Deals Gifts & Wish Lists Gift Cards Your Account Help an outer union followed by complementation. The schema of | | | Your Amazon.com | Today's Deals | | Giftsestimated & Wish Listsdelivery | Gift date Cards as soon as we have more information.Your Account |Your Help account 1 3d Laserinnengravuren will only be charged when we ship the item. IMDB: http://www.imdb.com Shop All Departments www.crystal-indesign.comSearch Music - Innovative Ideen aus dem Bereich der LasergravurMusicCart in KristallglasWish List Ships from and sold by Amazon.com . Gift-wrap available. the outer union of Police and Hospital is the union of schemas Shop All Departments Search Cart Wish List See larger image Music AdvancedFree 3D Search 3DSBrowse Models Genres New Releases Bestsellers Music Deals Music You ShouldAdvanced Hear SearchMusicBrowse Essentials Genres MP3New Downloads Releases Bestsellers Music Deals Music You Should Hear Music Essentials MP3 Downloads Music More Buying Choices of both tables, e.g., (Name, DOB, Sex, Address, Blood) and www.3dvia.com/ - Find, search and share the best 3D 3DS Sharemodels your online own customer images 2 new from $35.98 2 new from $35.98 Disney-WinkelTu Vas Pas Mourir De Rire [IMPORT] Tu Vas Pas Mourir De Rire [IMPORT] Get it for less! Quantity: 1 Mickey 3D (Artist) Mickey 3d (Artist) www.Disney-Winkel.nl Have one to sell? No customer reviews - Ruim yet. Be 3000 the first. Disney | More about Artikelen this product Direct op voorraad! Special OffersHaveNo customer one and to reviewssell? Product yet. Be the first.Promotions | More about this product Get $1 Listworth Price: of$35.99 MP3 downloads from Amazon MP3 after you order your item.or Here's how See a problemThis with item these has advertisements?been discontinued Let usby knowthe manufacturer. Advertise on Amazon Sign in to turn on 1-Click ordering. Share with Friends tid Name DOB Sex Address (restrictionsPrice: apply)$35.99 & ships FREE with Super Saver Shipping or or FREE Two-Day Shipping with a free trial of Amazon 1 Miller 7/7/59 m 12 Main Product Details SharePrime. with Details Friends 2 Peter 1/1/53 m 34 First tid Name DOB Sex Address Blood Audio CD (December 25, 2007) Product Details Special Offers Available Audio CD (December 25, 2007) Amazon Prime Free Trial (a) Police Number of Discs: 2 required. Sign up when you 1+5 Miller 7/7/59 m 12 Main O Temporarily out of stock. check out. Learn More Number ofOrder Discs: now and 2 we'll deliver when available. 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