That’s usual case. Skilled BW guy knows where to look in order to lookup information that is needed. It is common to know basic tables with IOs (RSDIOBJ), reports (RSRREPDIR), cubes (RSDCUBE), DSOs (RSDODSO), process chains (RSPCCHAIN) etc.
More technical BW guy would also know where to find information about basic BW system settings (tables RSADMINA, RSADMINS, RSBASIDOC, etc.).
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