Верзија 3
Определување функциски зависности и да нема нешто со исто име на атрибут
*s_id = statement_id R={ pe_id, first_name, last_name, gender, address, picture, contact, embg, date_of_birth,country, nationality, o_badge_no, o_password, o_date_of_employment, p_id, p_address, s_id, city, p_date_of_employment, badge_no, rank, p_password, statement_id, statement_date, description, incident_timestamp, incident_place, e_id, e_name, e_type, is_found, e_picture, c_id, c_name, opening_date, c_status, date_of_closing, sc_description, final_document, t_id, t_name }
pe_id -> first_name, last_name, gender, address, picture, contact, embg, date_of_birth, country, nationality o_badge_no -> s_id, pe_id, o_password, o_date_of_employment p_id -> p_address, o_badge_no, s_id s_id -> city badge_no -> pe_id, p_date_of_employment, rank, p_password statement_id -> c_id, statement_date, description, incident_timestamp, incident_place, badge_no e_id -> e_name, e_type, is_found, e_picture c_id -> c_name, opening_date, c_status, e_id, p_id, date_of_closing final_document-> sc_description, date_of_closing t_id -> t_name
### Лево
- statement_id
- final_document
- t_id
### Десно
- first_name
- last_name
- gender
- address
- picture
- contact
- embg
- date_of_birth
- country
- nationality
- o_password
- o_date_of_employment
- p_address
- city
- p_date_of_employment
- rank
- p_password
- statement_date
- description
- incident_timestamp
- incident_place
- e_name
- e_type
- is_found
- e_picture
- c_name
- opening_date
- c_status
- sc_description
- t_name
- date_of_closing
### Двете
- pe_id
- o_badge_no
- p_id
- s_id
- badge_no
- e_id
- c_id
statement_id+={statement_id ,c_id, statement_date, description, incident_timestamp, incident_place, badge_no,c_name, opening_date, c_status, e_id, p_id, date_of_closing, pe_id, p_date_of_employment, rank, p_password, first_name, last_name, gender, address, picture, contact, embg, date_of_birth, country, nationality, p_address, o_badge_no, s_id, city, e_name, e_type, is_found, e_picture}
не ги содржи сите атрибути
final_document+={final_document, sc_description, date_of_closing} не ги содржи сите атрибути
t_id+={t_id, t_name} не ги содржи сите атрибути
statement_id, final_document+={statement_id, final_document, c_id, statement_date, description, incident_timestamp, incident_place, badge_no, sc_description, date_of_closing, c_name, opening_date, c_status, e_id, p_id, pe_id, p_date_of_employment, rank, p_password, first_name, last_name, gender, address, picture, contact, embg, date_of_birth, country, nationality, p_address, o_badge_no, s_id, city e_name, e_type, is_found, e_picture} не ги содржи сите атрибути
statement_id, t_id+={statement_id, t_id, c_id, statement_date, description, incident_timestamp, incident_place, badge_no, t_name, c_name, opening_date, c_status, e_id, p_id, date_of_closing, e_name, e_type, is_found, e_picture, p_address, o_badge_no, s_id, city, pe_id, p_date_of_employment, rank, p_password, first_name, last_name, gender, address, picture, contact, embg, date_of_birth, country, nationality, o_password, o_date_of_employment} не ги содржи сите атрибути
final_document, t_id+={final_document, t_id, sc_description, date_of_closing, t_name} не ги содржи сите атрибути
final_document, t_id, statement_id+={final_document, t_id, statement_id, sc_description, date_of_closing, t_name, c_id, statement_date, description, incident_timestamp, incident_place, badge_no, c_name, opening_date, c_status, e_id, p_id, pe_id, p_date_of_employment, rank, p_password, e_name, e_type, is_found, e_picture, p_address, o_badge_no, s_id, o_password, o_date_of_employment, city, first_name, last_name, gender, address, picture, contact, embg, date_of_birth, country, nationality}
Следува дека е единствен кандидат клуч и го прогласуваме за примарен клуч.
`
в) Во ваква дефинирана релација нема повеќекратни зависности, па со тоа следува дека задоволува 1НФ.
Парцијална зависност постои, и со тоа заклучуваме дека не е задоволена 2НФ.
Декомпозиција:
R1{s_id, city} е во BCNF
R2{c_id, final_document, t_id, statement_id, sc_description, date_of_closing, t_name, c_id, statement_date, description, incident_timestamp, incident_place, badge_no, c_name, opening_date, c_status, e_id, p_id, pe_id, p_date_of_employment, rank, p_password, e_name, e_type, is_found, e_picture, p_address, o_badge_no, s_id, o_password, o_date_of_employment, first_name, last_name, gender, address, picture, contact, embg, date_of_birth, country, nationality}
---
R2 не е во 3НФ поради e_id -> e_name, e_type, is_found, e_picture
R21{e_id, e_name, e_type, is_found, e_picture} е во BCNF
R22{ final_document, t_id, statement_id, sc_description, date_of_closing, t_name, c_id, statement_date, description, incident_timestamp, incident_place, badge_no, c_name, opening_date, c_status, e_id, p_id, pe_id, p_date_of_employment, rank, p_password, p_address, o_badge_no, s_id, o_password, o_date_of_employment, first_name, last_name, gender, address, picture, contact, embg, date_of_birth, country, nationality}
---
R22 не е во 3НФ поради pe_id -> first_name, last_name, gender, address, picture, contact, embg, date_of_birth, country, nationality
R221{pe_id, first_name, last_name, gender, address, picture, contact, embg, date_of_birth, country, nationality}е во BCNF
R222{ final_document, t_id, statement_id, sc_description, date_of_closing, t_name, c_id, statement_date, description, incident_timestamp, incident_place, badge_no, c_name, opening_date, c_status, e_id, p_id, pe_id, p_date_of_employment, rank, p_password, p_address, o_badge_no, s_id, o_password, o_date_of_employment
---
R222 не е во 3НФ поради bange_no → pe_id, p_date_of_employment, rank, p_password
R2221{badge_no, pe_id, p_date_of_employment, rank, p_password} е во BCNF R2222{final_document, t_id, statement_id, sc_description, date_of_closing, t_name, c_id, statement_date, description, incident_timestamp, incident_place, badge_no, c_name, opening_date, c_status, e_id, p_id, p_address, o_badge_no, s_id, o_password, o_date_of_employment}
---
R2222 не е во 3НФ поради o_badge_no -> s_id, pe_id, o_password, o_date_of_employment
R22221{o_badge_no, s_id, pe_id, o_password, o_date_of_employment} е во BCNF R22222{final_document, t_id, statement_id, sc_description, date_of_closing, t_name, c_id, statement_date, description, incident_timestamp, incident_place, badge_no, c_name, opening_date, c_status, e_id, p_id, p_address, o_badge_no}
---
R22222 не е во 3НФ поради p_id -> p_address, o_badge_no, s_id
R222221{p_id, p_address, o_badge_no, s_id}е во BCNF R222222{final_document, t_id, statement_id, sc_description, date_of_closing, t_name, c_id, statement_date, description, incident_timestamp, incident_place, badge_no, c_name, opening_date, c_status, e_id, p_id}
---
R222222 не е во 3НФ поради c _id -> c_name, opening_date, c_status, e_id, p_id, date_of_closing
R2222221{c_id, c_name, opening_date, c_status, e_id, p_id, date_of_closing}е во BCNF R2222222{final_document, t_id, statement_id, sc_description, t_name, c_id, statement_date, description, incident_timestamp, incident_place, badge_no}
---
R2222222 не е во 3НФ поради t_id -> t_name
R222222221{t_id, t_name} е во BCNF R222222222{final_document, t_id, statement_id, sc_description, c_id, statement_date, description, incident_timestamp, incident_place, badge_no}
---
R222222222 не е во 3НФ поради final_document-> sc_description, date_of_closing
R222222221{final_document, sc_description, date_of_closing}е во BCNF R222222222{final_document, t_id, statement_id, c_id, statement_date, description, incident_timestamp, incident_place, badge_no}
---
R222222222 не е во 3НФ поради statement_id -> c_id, statement_date, description, incident_timestamp, incident_place, badge_no
R2222222221{statement_id , c_id, statement_date, description, incident_timestamp, incident_place, badge_no}е во BCNF
R2222222222{final_document, t_id, statement_id} е во BCNF
Релации
Sector_of_interal_affairs{s_id, city} е во BCNF
Evidence{e_id, e_name, e_type, is_found, e_picture} е во BCNF
People{pe_id, first_name, last_name, gender, address, picture, contact, embg, date_of_birth, country, nationality}е во BCNF
Policeman{badge_no, pe_id, p_date_of_employment, rank, p_password} е во BCNF
Officer{o_badge_no, s_id, pe_id, o_password, o_date_of_employment} е во BCNF
Police_station{p_id, p_address, o_badge_no, s_id}е во BCNF
Crime_case{c_id, c_name, opening_date, c_status, e_id, p_id, date_of_closing}е во BCNF
Type_of_crime{t_id, t_name} е во BCNF
Solved_case{final_document, sc_description, date_of_closing}е во BCNF
Statement{statement_id , c_id, statement_date, description, incident_timestamp, incident_place, badge_no}е во BCNF
Statement_and_case{final_document, t_id, statement_id} е во BCNF
*резултатот е различен од оригиналниот модел.
Дискусија на разликите:
Табелите каде што се чуваат acused, witness и victims се испуштаат. За да се реши ова би можело да има индиректна врска преку Statements со атрибут statement_of каде што можеме да имаме три вредности соодветно acused, witness и victims.
Редундантно повторување на слични атрибути, тоа се забележува кај Officer и Policeman. Едно решение за ова би било табела вработени каде што би се чувал атрибут is_officer. Со тоа би се изменила целосната структура на базата и не би ги имале officer и policeman.
Имаме исто така директна врска од Crime_case за Evidence, каде што во првичниот модел се индиректно поврзани преку Mentions_evidence и Statements.
