Which Select will be faster?

Question

SQL

mssql database. There is a table, type reference, I want to add a link field to it. I can not decide what type, string or integer?
which select will work faster:
select * from test_table where Code = 1
or
select * from test_table where Code = 'one' ?
How significant will the difference be on large volumes?

Answer 1

1) Faster than int (i.e. 1)
2) If you want faster, then select * is incorrect, because it works much slower than select [first_element], [second_element]... (i.e. selecting each element from the table)