Dab tsi yog drill down hauv cov ntaub ntawv warehouse?
Dab tsi yog drill down hauv cov ntaub ntawv warehouse?

Video: Dab tsi yog drill down hauv cov ntaub ntawv warehouse?

Video: Dab tsi yog drill down hauv cov ntaub ntawv warehouse?
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Drill Down thiab Laum Up (tseem hu ua Cov ntaub ntawv Drilling ) txhais tau tias mus rau hauv hierarchical qhov ntev ntawm cov ntaub ntawv khaws cia rau hauv Cov ntaub ntawv Warehouses . Muaj ob txoj kev sib txawv ntawm cov ntaub ntawv drilling : Drill Down yog siv nyob rau hauv Online Analytical Processing (OLAP) kom zoom rau kom ntxaws ntxiv cov ntaub ntawv los ntawm Hloov Dimensions.

Ib yam li ntawd, nws txhais li cas los tho cov ntaub ntawv?

xyaum . (v) Hauv cov ntaub ntawv thev naus laus zis, txav los ntawm cov ntaub ntawv qhia txog cov ncauj lus kom ntxaws cov ntaub ntawv los ntawm kev tsom mus rau ib yam dab tsi. Rau xyaum los ntawm ntau cov folders, piv txwv li, ntawm lub desktop txhais tau tias mus los ntawm cov hierarchy ntawm folders mus nrhiav ib cov ntaub ntawv tshwj xeeb los yog nyem los ntawm drop- nqes menus hauv GUI.

Ib yam li ntawd, dab tsi yog qhov txheej txheem drill down? Drill down yog ib qho yooj yim txheej txheem rau kev rhuav tshem cov teeb meem nyuaj nqes mus rau hauv cov khoom me me. Yuav siv lub txheej txheem , pib los ntawm kev sau qhov teeb meem nqes nyob rau sab laug ntawm ib daim ntawv loj. Txuas ntxiv mus drilling nqis mus rau hauv cov ntsiab lus kom txog rau thaum koj nkag siab tag nrho cov yam uas ua rau qhov teeb meem.

Tom qab ntawd, lo lus nug yog, yuav ua li cas lub tsev khaws ntaub ntawv ua cov lus nug?

Drilling Down . Drilling down hauv kev sib raug zoo database txhais tau hais tias "ntxiv kab header" rau ib nqe lus SELECT uas twb muaj lawm. Piv txwv li, yog tias koj tab tom soj ntsuam kev muag khoom ntawm cov chaw tsim khoom, xaiv cov npe ntawm cov khoom nug nyeem SELECT MANUFACTURER, SUM(SALES).

Dab tsi yog rollup nyob rau hauv cov ntaub ntawv warehouse?

ROLLUP , CUB in Cov ntaub ntawv Warehouses . Hauv kab lus no peb yuav pom cov no Cov ntaub ntawv warehouse SQL ntawv. ROLLUP yog siv xam subtotals nyob rau hauv ib pab pawg. ROLLUP yog ib qho yooj yim txuas mus rau GROUP BY clause.

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