Htmlentities vs addslashes vs mysqli_real_escape_string

Question

I\'ve been doing some reading on securing PHP applications, and it seems to me that mysqli_real_escape_string is the correct function to use when inserting data

Answer 1

They are different tools for different purposes.

mysqli_real_escape_string makes data safe for inserting into MySQL (but parametrized queries are better).

Htmlentities makes data safe for outputting into an HTML document

addslashes makes data safe for a few other situations, but is insufficient for MySQL