- Thanh to' khong day dd nhu khung mJu.
d mlic phan tich, thie'tke' hay cai ~t.
3.2.1 Ph~m vi dog dt;log cua h~ th6og qUaD Iy cae giaodich dijt tru'8c :
Khi xay dlfng cac h<$th6ng thong tin, chung ta thuong g~p cac yell
c~u nhu la: khach d~t mila hang, sinh vien dang ky man hQc, khach d~t ve du lich, ... nhfi'ng va"nd€ nay tuy nam trong cac h<$th6ng ling dIJng khac nhau nhung chung co cung mQt ban cha"t,do chinh la nhfi'ng cac giao dich d~t trudc. Va cac IInh vlfc ling dIJngkhac nhau do theo cach tie'p c~n thanh
to' duQc gQi la pht;lm vi zing dl;lngcua hf th6'ng.
Sail day la ph~m vi ling dIJng cua h<$th6ng quail Iy cac giao dich d~t tru'dc :
£)~t ve xem phim, dang ky h~n kham b<$nh,d~t ve cho mQt chuye'n du lich, d~t phong khach s~n, d~t ti<$clien hoan, dang ky muQn sach, dang ky tham dlf hQi nghi, dang ky thue nha, dang ky ghi danh mOll hQc, d~t
mila hang, qmln ly cac giao dich mila ban cua mQt don vi kinh doanh, ... Ph~m vi cua ling dl;}ngcua h~ th6ng co th~ du'Qc stl'a d6i, b6 sung d~
phu hQp cac va'n d~, cac yell c~u ma h~ th6ng da: du'a ra cach giai quy€t. N€u ph~m vi ling dl;}ngcua h~ th6ng cang d~y du thl kha nang dung l~i cua h~ th6ng cang cao.
Sail khi du'a ra ph~m vi ling dl;}ngcua h~ th6ng quail ly cac giao dich
d~t tru'dc, chung ta se du'a ra cac ml;}ctieu c~n phai giai quy€t cho cac ling dl;}ngtrong tu'ong lai thuQc ph~m vi ling dl;}ngnay (xem trlnh bay chi ti€t
trong ml;}c4.1), va cach ti€p c~n thanh t6 da: du'a ra mftu phan tkh d~ h6 trQcho giai do~n phan tich h~ th6ng quail ly cac giao dich d~t tru'dc.
3.2.2 Xay dt;ing mftu philo tieh trong giai do~n philo tieh h~ th6ng qmin Iy cae giao dieh d~t trdde:
MQt thi€t k€luon luon d~t hi~u qua khi ffiOhinh phan tkh r6 rang va logic nha't, bC'5iVInhung mo hinh r6 rang luon cho ngu'oi ta nh~n tha'y du'Qc co hay khong cai ma hQ c~n.
Trong giai do~n phan tkh, vdi ffil;}Ctieu phai d~t du'Qccua h~ th6ng,
dl;l'avao mo hinh phan tkh cua ffiQt s6 h~ th6ng ling dl;}ng [10] va mQt s6 chi€n lu'Qc va mftu phan tkh cua [3], chung ta se du'a ra mQt mftu phan tkh
d~y du nha't cho h~ th6ng. Trong mftu phan tkh nay, khai ni~m rang buQc
t6ng quat hoa va chuyen bi~t hoa (ngl;}yr~ng cac ldp con k€ thua du li~u va cac phu'ong thlic cua ldp cha) du'Qcdu'a ra d~ nh~n bitt co mQt h~ th6ng ca'pb~c chuyen bi~t hoa giua ldp cha la :CHITIETGIAODICH va ldp con
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c~u trong th\lc t€ v€ ffiQt chi ti€t giao d~ch co th~ hoan loan kbac nhal
trong illQt giao dich dl1qc d~t, yi 011-'-
chuy€n bay trong ffiQtch
d~ttntdc :