sql server - When do column indexes become "worth it" -


for given single table has more 1 column against using where clause, columns int or bigint, @ point become worth creating index on columns.

i aware should create columns anyway, question when performance advantage of having indexes there, kick in in terms of table size.

instantly, granted wouldn't notice on small table, needs table scan if index isn't in place on these columns.

so in execution time wouldn't notice if @ cpu used query, , reads you'll notice index query instantly start performing better.


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