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🀘Security Warning: This answer is not in line with security best practices. Correctly setting up the connection Note that when using PDO to access a MySQL database real prepared statements are not used by default. By specifying parameters either a? This answer lacks the explanation of what is a prepared statement - one thing - it's a performance hit if you use a lot of prepared statements during your request and sometimes it accounts for 10x performance hit. And it gives the developer the chance to catch any error s which are thrown as PDOExceptions. Deprecated Warning: This answer's sample code like the question's sample code uses PHP's MySQL extension, which was deprecated in PHP 5. Edit existing answers to improve this post. This way the script will not stop with a Fatal Error when something goes wrong. The important thing here is that the parameter values are combined with the compiled statement, not an SQL string. Then when you call execute, the prepared statement is combined with the parameter values you specify. Better case would be use PDO with parameter binding off, but statement preparation off. 0 and removed entirely in PHP 7. What is mandatory, however, is the first setAttribute line, which tells PDO to disable emulated prepared statements and use real prepared statements. You basically have two options to achieve this:β€’ Both would protect you from SQL injection. We'll cover the lower impact string escaping one first. So by sending the actual SQL separately from the parameters, you limit the risk of ending up with something you didn't intend. SQL injection works by tricking the script into including malicious strings when it creates SQL to send to the database. To fix this you have to disable the emulation of prepared statements. This way it is impossible for an attacker to inject malicious SQL. Use prepared statements and parameterized queries. Another benefit of using prepared statements is that if you execute the same statement many times in the same session it will only be parsed and compiled once, giving you some speed gains. The parameterized query is considered the better practice but will require changing to a newer MySQL extension in PHP before you can use it. This makes sure the statement and the values aren't parsed by PHP before sending it to the MySQL server giving a possible attacker no chance to inject malicious SQL. Explanation The SQL statement you pass to prepare is parsed and compiled by the database server. , use prepared statements instead. It is not currently accepting new answers or interactions. Although you can set the charset in the options of the constructor, it's important to note that 'older' versions of PHP before 5. While you can still use prepared statements for the query parameters, the structure of the dynamic query itself cannot be parametrized and certain query features cannot be parametrized. Any parameters you send when using a prepared statement will just be treated as strings although the database engine may do some optimization so parameters may end up as numbers too, of course. or a named parameter like :name in the example above you tell the database engine where you want to filter on. This question's answers are a. Use the strategy outlined below at your own risk. These are SQL statements that are sent to and parsed by the database server separately from any parameters. For these specific scenarios, the best thing to do is use a whitelist filter that restricts the possible values.。 。

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