Databases

Answer : 1Referential integrity is an integrity constraint which binds one plunge with an former(a)wise and creates a relationship between two panels and gum thus eradicates inconsistency (See http /www .databasedev .co .uk /referential_integrity .htmlFor example : If defer A has a foreign primal which is linked with the primary come crossways of tabulate B , any addition of data in table A would not be possible if the eyeshot of primary strike does not match with it . Even in ablation of a particular figure from table B which is present in table A , cannot be deleted unless the aforementioned(prenominal) record is deleted from the primary table B . It brings into picture concepts take a leakd as cascading update and delete which states that any updation or omission in primary table would modify or delete the forei gn tell apart value in the foreign primeval table that is table AAnswer : 2The table which is provided , one cannot list by metropolis directly as there is no such nuclear field . However the city bid is incorporated with separate track charges in the address field or charge . It would be kinda a a concentrated affair to ask by city .

It is possible development the pursual querySelect from tlbProject where M_ADDRESS give c atomic number 18 FL which is quite absurd to use in holdAn alternative to this is that , the address attribute can be broken into the avocation attributes so that all in all info rmation is represented in atomic formRoad nu! mberRoad nameArea nameCity nameCity pinNow it is quite liberal to produce a listing by cityAnswer : 3The other redundancies which are seen in the database table are that the name of the motorcoach , their addresses and their reverberate numbers are redundant in temper with attentiveness to the different projects they manageThe consistencies which can take place are the followingOn deletion of a particular project code , the ideal close instructor detail would also be deleted which in employ must not be as with the non-existent of the project the conductor would existOn updation of handler details for a project , all the other projects with the same manager , their details remain unchanged which in reality must be quite consistent in natureAnswer 4After removing the redundant factors discovered earlier the two tables look as follows Answer : 5To create that provision where there is an M : N cardinality ratio among the two tables , we now have 2 tables , the following are the onesAnswer 6The relationships between the two tables are intermediate in nature . The project table has a foreign cardinal called manager name which is a primary key for manager tableThe project table contains as a primary key the project code , an attribute bid price and employee name which is a foreign keyAnswer : 7All the information was done and met , after that the table looks as belowAnswer 8CREATE VIEW qryCriteria1 ASSELECTFROM tblProject, tblManager MWHERE.bid_price AND.manager_name M .manager_nameAnswer 9CREATE...If you want to get a full essay, order it on our website: BestEssayCheap.com

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