How can I show the limitations of my index in SQL

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Hello everyone, I created two B-tree indexes in the popular employees database and I want to write sql queries to show some limitations of these indexes. The query I have below can't prove anything using one of the indexes that I created. Please can anyone show me a query that can show some limitations of these indexes ? Thanks for any help.

What I have tried:

use employees;

CREATE INDEX indx_emp on employees(emp_no);

CREATE INDEX indx_gen on employees(gender);

SELECT 
    *
FROM
    employees USE INDEX (INDX_EMP)
WHERE
    emp_no BETWEEN 10980 AND 100000
        AND gender = 'M'
ORDER BY birth_date;

Posted 4-Apr-21 18:16pm

UT7

Updated 6-Apr-21 22:05pm

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CHill60 6-Apr-21 9:39am

What do you mean by the "limitations of these indexes"?

UT7 6-Apr-21 22:55pm

I want to show situations where this index would be ineffective searching the database. Thanks.

[no name] 6-Apr-21 15:45pm

There is no "USE INDEX" option.

UT7 6-Apr-21 22:57pm

"USE INDEX" is there, please check. Thanks.

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CHill60 · Accepted Answer · 2021-04-06T22:05:00

You appear to be trying to use the "USE INDEX Hint" and noting the relative effects of various indexes.

These blogs from Pinal Dave will give you an introduction:
SQL SERVER - Introduction to Force Index Query Hints - Index Hint - SQL Authority with Pinal Dave[^]
SQL SERVER - Introduction to Force Index Query Hints - Index Hint - Part2 - SQL Authority with Pinal Dave[^]

There are some articles here on Code Project about using the SQL Profiler - you will need something like this to compare the results
SQL Server Profiler Step by Step[^]
MS SQL Server Profiler with .NET[^]

This one is now unfortunately out of date and no longer kept up to date, but probably still worth a read - Tools of the Trade: SQL Server Profiler and Query Analyzer | Microsoft Docs[^]