MDX yog lus nug tsim los rau OLAP databases, raws li SQL yog lus nug rau cov ntaub ntawv sib txheeb. MDX yog qhov tseem ceeb tshaj plaws rau SQL siv rau cov lus nug thiab tsab ntawv nkag mus rau cov ntaub ntawv ntau yam. MDX cov lus nug nkag mus rau cov ntaub ntawv khaws cia hauv SQL Server Analysis Server lub voos xwmfab los ntawm kev nqa rov qab qhov tseeb ntsig txog qhov ntev.
MDX lus nug ua haujlwm li cas?
MDX cov lus nug tuaj yeem muaj 0, 1, 2 lossis txog 128 cov lus nug axes hauv SELECT nqe lusTxhua axis coj zoo ib yam, tsis zoo li SQL qhov twg muaj qhov sib txawv tseem ceeb nruab nrab ntawm yuav ua li cas cov kab thiab kab ntawm cov lus nug coj tus cwj pwm. Raws li nrog cov lus nug SQL, FROM clause npe lub hauv paus ntawm cov ntaub ntawv rau cov lus nug MDX.
MDX lus nug siv nyob qhov twg?
MDX (Multi – Dimensional eXpressions) yog cov lus nug siv txhawm rau khaws cov ntaub ntawv los ntawm ntau qhov chaw khaws ntaub ntawv. Tshwj xeeb tshaj yog, MDX yog siv los nug cov ntaub ntawv ntau yam los ntawm Kev Tshawb Fawb Kev Pabcuam thiab txhawb nqa ob hom sib txawv.
nqe lus MDX yog dab tsi?
Multidimensional Expressions (MDX) yog lus nug rau kev ua haujlwm hauv online (OLAP) siv cov txheej txheem tswj hwm database. Zoo li SQL, nws yog lus nug rau OLAP cubes. Nws kuj yog ib hom lus suav nrog, nrog syntax zoo ib yam li cov qauv ntawv.
MDX lus nug hauv SAP BW yog dab tsi?
Multidimensional Expressions (MDX) yog ib hom lus rau kev nug cov ntaub ntawv ntau yam uas tau khaws cia hauv OLAP cubes. MDX siv cov ntaub ntawv ntau yam qauv los ua kom muaj kev taw qhia hauv ntau qhov ntev, qib, thiab nce thiab nqis ib qib siab. … Nco ntsoov MDX yog tus qauv qhib.