Preprocessing techniques for MySQL operations in PHP (2) Database DQL query statements

<?php//preprocessing Technology//Create a Mysqli object $mysqli = new mysqli ("hostname", "MySQL User name", "Password", "database Name");//Determine if the link succeeds if ($mysqli->connect_ Error) {die ($mysqli->connect_error);} Create precompiled Object $sql = "Select id,name,age,qq from table name where id<?"; $mysqli _compile = $mysqli->prepare ($sql);//bind parameter $id=10;//give? Assignment, "SSI" means string,string,int, data type and order one by one corresponds to//bind_param () here the number of parameters is variable. $mysqli _compile->bind_param ("i", $id);//Bind the result set, here is the way $mysqli_compile->bind_result ($name, $age, $QQ) with reference to the parameter;// Execute statement $res = $mysqli _compile->execute ();//failed to print out the reason if (! $res) {die ("failure reason =". $mysqli _compile-error);} Remove the bound result value while ($mysqli _compile->fetch ()) {echo "--$id--$name--$age--$QQ";} If you want to take other results, you can bind the parameter again, but not bind the result set//release the result set $mysqli_compile->free_result ();//close the resource and drop the precompiled instruction of the database $mysqli_compile- >close ();//Close Link resource $mysqli->close ();? >