You can put place holders in the where clause. However you can't place hold the field name .. only it's value. for instance you couldn't say...

my $query = q{SELECT *
              FROM my_table
              WHERE ? LIKE ?};
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however

my $query = q{SELECT *
              FROM my_table
              WHERE my_field LIKE ?};
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will be valid, so long as your placeholder contains the appropriate like operator ie % or whatever is appropriate for your RDBMS