Tích hợp dữ liệu và nhiệm vụ xây dựng hệ thống cơ sở dữ liệu Quốc gia về biến đổi khí hậu

Nghien ciiu - Trao doi

Jich hop duf lieu va nhiem vu

xay dirng he thong cb soi diif lifu Quoc gia

ve bien doi Khi hau

O KS. NGUVeN HUTU CHINH

Cue Cdng nghe Thdng tin - Bd TN&MT

N

ham tQng budc tridn khai tdt ede vdn ban

QPPL dd ban hdnh, vd Chuong trinh muc

tiSu qudc gia dng phd vdi BDKH, Bd

TN&MT dd tridn khai de tdl "NghiSn edu cff sd

khoa hgc, cdng nghe xay dyng he thdng CSDL

Qude gia ve BDKH vd tdc ddng cua BDKH phuc

vy dng phd vdi BDKH", trong dd ed ndi dung

"Nghien cdu khung kidn trdc he thdng CSDL

Qude gia vd BDKH vd tdc ddng cua BDKH phyc

vy dng phd vdi BDKH". Trong khudn khd cua

mdt bdi bao, tdc gia se dua ra giai phap tich hpp

dQ lieu trong khung kidn true he thdng CSDL

Qudc gia da de xud't.

Tong quan ve tich hpp dfl lieu

Vin de tich hgp dUlidu

Khi ndi ddn tfeh hpp dfl lieu, ta thfldng hinh dung

ngay ddn vide tong hpp thdng tin tfl nhieu ngudn dfl

lidu san cd cDa cde he thdng khac nhau, hay tren

cDng mpt hd thdng thanh phan mpt ngudn dfl lieu

mdi cd the dung eho mdt he thdng mdi nao do hay

chl de luu trfl.

Vay, cdc cdng viec trong vide tfch hpp dfl lieu la

gi? ChDng dupe thue hien nhu thd nao? trinh tu ra

sao? Ta se lan lupt di vao tflng van de, bat dau tfl

khdi nidm vd tfeh hpp dfl lieu.

Khai niem tich hgp dU lieu

Tich hpp dfl lieu Id mpt khai niem kha trflu tupng,

tham chf la hoi md ho khien nhieu ngudi khdng the

(^nh nghTa chfnh xae va cu thi. Thdng thudng, tieh

hpp dfl lieu dupe hilu la qua trinh ket hpp dfl lieu tfl

nhieu ngudn thdng tin khac nhau nham cung cap

cho ngudi dung mdt cai nhin tong quan va duy nhdt

vd cac dfl lieu ndy.

Ddc diim cOa he thd'ng tich hgp dHlieu

Cac ngudn dfl lidu la phan tan. cae ngudn dfl lidu

nay cd thi la co sd dfl lidu (CSDL) trong eae he thdng

30 Tdl nguyfen va fvloi truong | KV 1 - Thing 9/2015

khac nhau, eOng cd the la cac trang web o cac dja chl

khac nhau, hoac cung cd the la nhflng con ngudi v6i

eac quan diem khae nhau ve mpt van de ndo do.

Cdc ngudn dfl lieu la khdng ddng nhat. Sir

khdng ddng nhat nay thi hien d eae ngdn ngfl bi^u

dien va tfl vflng bilu dien dfl lieu. Cae nguon dfl lieu

CO thi ed ngdn ngfl bilu dien khae nhau. Vf du,

CSDL cDa mpt ngudn dupc bieu dien theo dang

XML, nhung mpt ngudn dfl lidu khdc lal dflpc bieu

dien theo CSDL quan he. Cdc ngudn dfl lieu cung co

thi sfl dyng cdc tfl vung khac nhau d l cung bleu

dien mpt dfl lieu.

IWpt he tfch hpp dfl lieu thudng khdng can to^n

bp thdng tin dfl lieu trong cde ngudn can tfch hpp.

Vdi mdi nhidm vu cu thi, he thdng ehi can nhflng dil

lieu lien quan den vide thflc hien nhidm vu dd. Nhtf

vdy, neu tap hpp toan bp cac ngudn dfl lieu va \\h

thd'ng trudc khi tfch hpp thi se rat lang phf va nhilu

khi khdng thi thuc hidn 6\sgc.

Vdi nhiJmg dac diem neu tren, vide xdy dtmg he

thd'ng tfeh hpp dfl lieu yeu cau kidn thflc vd nhieu iinh

vuc khdc nhau nhu ly thuydt ve CSDL, cdc phUdng

phap ude lupng, \^ thuyet vd ngdn ngflva bieu di§n

thdng tin... Do vdy, khi xay dung hd thdng tfeh hpp dil

lieu eho Itnh vuc nao, can phai tim hilu sau ve ITnh

vflc do, va cdn thiet phai ed sfl tham gia cDa cac

chuydn gia trong fTnh vuc vao dydn.

Cdc mUc do tich hgp dU lieu

Theo Khaled Bashir Shaban, tfeh hpp dfl lieu

dupc ehia thanh ba mfle dua vao dac dilm dau vao

va ddu ra cDa qua trinh tfch hpp.

MUc I: Tfeh hpp dfl lieu. Day la mfle thap nhat,

Trong mflc ndy, dau vao la eac ban ghi dfl lieu, diu

ra cung cd dang eac ban ghi dfl lieu hoac mdt dang

eao hon nhflng van ddng vai trd la dfl lieu cung c^p

eho mdt Ung dung nao do.

MUc II: Tfch hpp thdng tin. Trong mflc nay, ca