the problem with this is that nothing is done for the case where the query failed and in most cases a failed query is a fatal problem, due to a programming mistake. Unlike bind_param(), our helper function accepts strings as parameters, hence you can add percent marks right at the call time.$result = $mysqli -> query("SELECT * FROM mytable") conditional around the query() code insures that the // do something code is only executed if the query() was successful. $rows = $stmt -> get_result ()-> fetch_all ( MYSQLI_ASSOC ) // fetch an array of rows $stmt = prepared_query ( $conn, $sql , ) With it, the code will become two times shorter: $sql = "SELECT * FROM users WHERE name LIKE ?" // SQL with parameters If you, like me, hate useless repetitions and like to write concise and meaningful code, then there is a simple helper function. ![]() ![]() If you like to build a code like a Lego figure, with shining ranks of operators, you may keep it as is. $rows = $result -> fetch_all ( MYSQLI_ASSOC ) // all rows matched Using a helper functionĪs you may noted, the code for a prepared statement is quite verbose. $result = $stmt -> get_result () // get the mysqli result $stmt -> bind_param ( "s", $name ) // here we can use only a variable $sql = "SELECT * FROM users WHERE name LIKE ?" // SQL with parameters Knowing that now we can create a prepared statement with LIKE: $name = "% $name %" // prepare the $name variable ![]() So we must prepare our variable before binding it. Hence, a code like this $stmt->bind_param("s", "%$var%") won't work, causing "Only variables can be passed by reference" error. bind_param() function accepts only variables, and strings are not allowed.Then ,a variabe that would contain something like '%search string%' can be bound to a placeholder the regular way. Hence, the percent marks should be added to the source variable instead. Hence, an SQL like this field LIKE '%?%' won't work. A placeholder cannot represent an arbitrary part of a query but only a whole data literal (or, to put it simpler, a string or a number).However, there are two certain gotchas that one should keep in mind: In general, SELECT with LIKE is no different from any other SELECT query with prepared statements. ![]() Using mysqli prepared statements with LIKE operator in SQLīefore running any query with mysqli, make sure you've got a properly configured mysqli connection variable that is required in order to run SQL queries and to inform you of the possible errors.
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