sql server - What is the cost of file organizations: heap file, sorted file, unclustered hash index on a delete operation using equality condition on a key? -


i learning database right now. knows nothing sql server. :-p

i see question don't know how answer it.

consider delete operation specified using equality condition on key. assuming no record qualifies, cost 3 file organizations: heap file, sorted file, unclustered hash index?

anyone answer question? thank :-)

for sql server 2014 (you tagged sql server , there no nc hash indexes in sql server before), answer io cost heap table reading pages constitute table, clustered index (sorted file) depends on depth of b tree structure, , unclustered hash index lookup hash table. of these should include 1 or more reads on metadata pages (iam , such).


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