when i do a generic access inquiry why do i get these results also

Document ID : KB000093080
Last Modified Date : 26/04/2018
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Question:
My request was WHOHAS DSN(+++TST) 

besides getting results that are an exact match to the inquiry I also get items that have additional generic characters in the listing 

DATASET(++++++++.) ACCESS(ALL) ACTION(AUDIT) 
DATASET(++++++.) ACCESS(ALL) ACTION(AUDIT)
Answer:
The DATASET(++++++++.) and DATASET(++++++.) are showing up because they allow access to DSN(+++TST). The '+' represents any single character, so the '+' in positions 4, 5, and 6 include 'TST'. 

The WHOHAS command does the equivalent of a WHOOWNS command, and then, for each ownership found, does the equivalent of the original WHOHAS command. When a TSS WHOHAS command is issued, TSS does not search every owned mask, however, in this case, since the mask ownership is the same (owned as dataset '++') for the dataset requested (+++TST) and the masked qualifiers ('++++++++.' and '++++++.', those other masked entries will show up in the output.