Dalilai da Matsayinsu a cikin Database

Masu ƙayyade gane ƙididdiga waɗanda aka sanya zuwa wasu halayen

Mai ƙayyadewa a cikin teburin layi yana da alamar da za a iya amfani dasu don ƙayyade dabi'u da aka sanya zuwa wasu halayen a jere guda. Ta wannan ma'anar, kowane maɓalli na farko ko maɓallin dan takarar shi ne mai ƙayyade, amma akwai ƙayyadaddun waɗanda ba na farko ba ne ko maɓallin dan takarar.

Alal misali, kamfanin zai iya amfani da tebur tare da halayen , da .

Employee_id Sunan rana Sunan mahaifa Ranar haifuwa

123

Megan Brown 01/29/1979
234 Ben Wilder 02/14/1985
345 Megan Chowdery 2/14/1985
456 Charles Brown 07/19/1984


A wannan yanayin, filin yana ƙayyade wurare guda uku. Sunan sunayen ba su ƙayyade domin kamfanin na iya samun ma'aikatan da suka raba wannan suna ko sunan karshe. Hakazalika, filin ba ya ƙayyade ko filin sunayen ba saboda ma'aikata zasu iya raba ranar haihuwa.

Dangantakar Mahimmanci ga Ƙananan Ƙarin Bayanai

A cikin wannan misali, wani mai ƙayyade, maɓallin dan takarar, kuma maɓallin maɓallin farko. Yana da maɓallin dan takarar domin lokacin da aka bincike dukkanin layin 234, jere da ke dauke da bayanin game da Ben Wilder ya bayyana kuma babu wani rikodin da aka nuna. Wata maɓallin dan takarar yana faruwa ne lokacin da kake bincika bayanai ta hanyar bayanin a cikin ginshiƙai uku; da , wanda ya dawo da wannan sakamakon.

A shine maɓallin farko saboda dukan haɗuwa da ginshiƙai waɗanda za a iya amfani dasu a matsayin maɓallin dan takarar, shi ne mafi kusantar shafi don amfani da shi a matsayin mahimmin tunani zuwa wannan tebur.

Har ila yau, an tabbatar da cewa ya zama na musamman ga wannan tebur, komai yawancin ma'aikatan da suke, amma ba daidai da bayanin a wasu ginshiƙai ba.