Joint Index Establishment basis

A high degree of differentiation is placed in front

Select COUNT (Distinct destinationmachine) CDD, COUNT (distinct factoryname) CDF, COUNT (distinct RequestType) CDR, COUNT (distinct Cassettetype) CDC, COUNT (distinct state) CDs From Dsptransfercommand;

CDD CDF CDR CDC CDS

----------  ---------   ----------     ----------     ----------

259 4 4) 2 8

Select Count (*) from Dsptransfercommand Total Table Calculation

Select the column for which the index is good to put in front.

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Joint Index Establishment basis