"20" mysqli based on process-oriented and object-oriented programming

process-oriented approach

Musqli Expanding library Operations MySQL database steps:

1. Get the connection and select the database

// Grammar Mysqli_connect (host,username,password,dbname,port,socket);    $conn=mysqli_connect("127.0.0.1", ' Root ', ' ', ' user ');     if (! $conn {        die ("link Failed");    }

2. Set the Operation code

// syntax: Mysqli_set_charset (Connection,charset);//Modify database connection character set to UTF8mysqli_set_charset ($conn, "Utf-8") ;

3. Sending SQL instructions (divided into DDL statements and DML statements, DQL statements, DTL statements)

• DDL statements: Data definition statements
• DML statements: Data manipulation statements (update ', insert, delete)
• DQL statement: (SELECT)
• DTL statement: Data transaction statement (rollback, commit)

Query data (DML statement): Returns a result set

        //EnquiryStatement        $sql= "SELECT * from User1"; //Execute SQL statement    $res=Mysqli_query($conn,$sql); //\ Print returns results as a result set    Var_dump($res); result set:Object(Mysqli_result)#2 (5) {//["Current_field"]=> int (0)//["Field_count"]=> int (5)//["lengths"]=> NULL//["Num_rows"]=> Int (6)//["type"]=> int (0)//}    Echo"<br/>"; Echo"----".$res-num_rows;//take data from the result set     while($obj=Mysqli_fetch_object($res)) {        Var_dump($obj); foreach($obj  as $key=$value) {            Echo"$key------$value"; Echo"<br/>"; }        Echo"<br/>"; }    

Name of function	Description
Mysqli_fetch_assoc ($result)	query to a data returned as an associative array [key]=>value
Mysqli_fetch_row ($result) takes the next row of data from the $res result set	query to a data returned as an indexed array [0]=>value
mysqli_fetch_array ($result)	query to a data returned in a mixed form of an indexed array and an associative array [key]=> Valuec/[0]=>value
mysqli_fetch_object ($result)	query to a data is returned as an object property  object{[key]=>value}
mysqli_fetch_array ($result)	query to one The data is returned in a mixed form of an indexed array and an associative array
mysqli_fetch_array ($result, Mysqli_both)	a query to The data is returned in a mixed form of an indexed array and an associative array
mysqli_fetch_array ($result, MYSQLI_ASSOC)	a query to The data is returned in a mixed form of associative arrays
mysqli_fetch_array ($result, mysqli_row)	query to one The data is returned in a mixed form of an indexed array

Delete and change (DML statement): Returns a Boolean value

    $sql= "INSERT into user1 (name,password,email,age) VALUES (' Haha ', MD5 (' 123456 '), ' [email protected] ', 16);"; $res=Mysqli_query($conn,$sql) or die("Execution Failed"); Var_dump($res);//The return is a Boolean value    if(!$res) {        Echo"Delete Failed"; }    EchoNumber of rows affected:.mysqli_affected_rows($conn); if(mysqli_affected_rows($conn) >0){        Echo"Add Success"; }Else{        Echo"Number of rows not affected"; }    

4. Releasing Resources

Note: Releasing the result set and closing the connection is not the same as filling in the resources

    // releasing the result set    Mysqli_free_result ($res);      // function to close a previously opened database connection    Mysqli_close ($conn);

Object-oriented approach

sqltool.class.php

<?PHPclasssqltool{Private $conn; Private $host= "localhost"; Private $user= ' Root '; Private $password= ' '; Private $db= ' user '; //construction method, initializing the connection database and setting character encoding         function__construct () {$this->conn=Mysqli_connect($this->host,$this->user,$this->password,$this-db); if(!$this-conn) {                 die("Connection failed.")Mysqli_error()); } mysqli_set_charset ($this->conn, "UTF8"); }        //executes a DML statement and returns a value        functionEXCUTE_DML ($sql){            $res=Mysqli_query($this->conn,$sql) or die("Shiai").Mysqli_error(); if(!$res) {                return0; }Else{                //mysqli_affected_rows: And the number of rows affected                if(mysqli_affected_rows($this->conn) >0) {                    return1; }Else{                     return2; }            }        }        //executes the DQL statement and returns the value        functionEXCUTE_DQL ($sql){            $res=Mysqli_query($this->conn,$sql) or die("Shibai"); //Var_dump ($res);            return $res; }    }

testsql.php

<?PHPrequire"Sqltool.class.php"; //$sql = "INSERT INTO User1 (name,password,email,age) VALUES (' Hhhhhh ', MD5 (' 123 '), ' [email protected] ',");    $sql= "Delete from User1 where name= ' QQ '"; $sqltool=NewSqltool (); //invoke DML    $res=$sqltool-&GT;EXCUTE_DML ($sql); if($res==0) {         Echo"Execution Failure <br/>"; }Else if($res==1) {        Echo"Execution Success <br/>"; }Else if($res==2) {        Echo"No impact to line count <br/>"; }    $sql 1= "SELECT * from User1"; //Call DQL    $res 1=$sqltool-&GT;EXCUTE_DQL ($sql 1); //Var_dump ($res 1);    if($res 1->num_rows>0) {         while($row=Mysqli_fetch_row($res 1)) {            //Var_dump ($row); echo "<br/>";            foreach($row  as $key=$value) {                Echo"---$value"; }            Echo"<br/>"; }        }?>

"20" mysqli based on process-oriented and object-oriented programming