Partial preview of the text
Download PU DATABASE SOLVED PAST PAPER and more Papers Database Management Systems (DBMS) in PDF only on Docsity!
Dato Fondependente: a type of _indepenclence that enable the user re internal evel without changing the concepluall devel that may be performed at physical Level are as follow: - 2 Changing _ file. organizahons or Storage Steuctureg = asia different Storage devices _ Modifying _tndeves + Changing the access method - 4 a- Logical dlata. 9ndependlence: - ie Geers “a type of independence that enables the user to change the conceptual Devel without changing the extemal devel. The daiiee : _- that _may be performed at this lve! are as follow: | - Addition ot pgemovol of entities ot xelakonships : Adding. & fide to the database + Adding new _feld in file on shanging the type of a field ete- 4 is database integrity 2 How it canbe enforced? Pager ee ee ee inleptity vefers to accuragy- sep p da Labase - 9t predetineg in_ovdex to mmimize redundaney ns before/after the intext , update limitations of hierarchicha! model > 7 of hierarchical model include : yehicka! models can bead to data__zedundane tela to ship Trequires repeated data. : om ondy suppost parent-child aelabions bp amaking it dif feubt 1 __compley relationships between data entities. __ hrerarchica) data can be complex and inefficient. ewigit struchrses making it challenging if busines weguivements ee database grows , hreraxchica) models can become 4s otmance tssues ond difficulty tp mamta'n 28S each paren gt “y er +t 000 and é000 Scarnad wish CamSeaner Scarnad wish CamSeaner _ORD-1D DITEMEID is tamposits key + Pastial dependencies: __> CUST_NAME , CUST.-ADDRESS are dependent only on Imem_wame _, 1tem_pRice are dependent only on ITEM_ID. Spit the table ; 2, Orders Table __ ORD_ID | ORD_OATE _CUST-ID. el 14/03/2021. C- | 15/03/2091 bc -102. | lol > Customers table CUST. _CUST.ID _CUST_NAME _ ADDRESS -> Items table Clo Naveed | Lahore | _e-lor | Amjad | Quetta - aes items per i” j (Tém-tb | ITeEm.OTY [TEM.1D__ITEM-NAME TEM-PRUCE 4 oo a tis Pe eee ae | Scanner | 18000 ate | 3: 100 Ene af Mouse $00 3 40 eet eae Psintes 80 ig 50 1 4 Monitor. 
