MySQL operations using mysqli extension library in PHP

1. Use mysqli extension library in PHP to perform dql operations on MySQL

<? PHP  Header ("Content-Type: text/html; charset = UTF-8" );  //  Mysqli operations on the MySQL database (Object-Oriented) // 1. Create a mysqli object      $ Mysqli = New Mysqli ("localhost", "root", "root", "test" );  If ( $ Mysqli -> Connect_error ){  Die ("Connection failed ".$ Mysqli -> Connect_error );}  //  2. operate databases (send SQL statements)      $ SQL = "Select * From user1" ;  //  3. processing result      $ Res = $ Mysqli -> Query ( $ SQL  );  //  Var_dump ($ res); // fetch_assoc \ fetch_array \ fetch_object     While ( $ Row = $ Res -> Fetch_row ()){  Var_dump ( $ Row  );  /*  Foreach ($ row as $ Val) {echo '--'. $ val;} echo '<br/> ';  */  }  //  4. Close Resources      $ Res ->Free ();  $ Mysqli -> Close (); ?>

The following process-oriented

<? PHP  Header ("Content-Type: text/html; charset = UTF-8" );  $ Mysqli = Mysqli_connect ("Localhost", "root", "root", "test" );  If (! $ Mysqli  ){  Die ("Connection failed ". Mysqli_connect_error  ());}  $ SQL = "Select * From user1" ;  $ Res = Mysqli_query ( $ Mysqli , $ SQL  );  //  Var_dump ($ res );      While ( $ Row = Mysqli_fetch_row ($ Res  )){  Foreach ( $ Row   As   $ Val  ){  Echo '-'. $ Val  ;}  Echo '<Br/>' ;}  //  Release memory      Mysqli_free_result ($ Res  );  Mysqli_close ( $ Mysqli  ); ?>

2. Use the mysqli extension library in PHP to perform DML operations on MySQL

<? PHP  //  Crud operations on MySQL using mysqli extension Library      Header ("Content-Type: text/html; charset = UTF-8" );  $ Mysqli = New Mysqli ("localhost", "root", "root", "test" ); If ( $ Mysqli -> Connect_error ){  Die ("Connection failed ". $ Mysql -> Connect_error );}  //  Add a record // $ SQL = "insert into user1 (name, password, email, age) values ('Lucy ', MD5 ('Lucy'), 'Lucy @ 163.com ', 17) "; // delete a record // $ SQL =" delete from user1 where id = 80 "; // update a record      $ SQL = "Update user1 set age = 20 where id = 7" ;  $ Res =$ Mysqli -> Query ( $ SQL  );  If (! $ Res  ){  Echo "Operation failed ". $ Mysqli -> Error ;}  Else  {  If ( $ Mysqli -> Affected_rows> 0 ){  Echo "Successful" ;}  Else  {  Echo "No rows affected" ;}}  //  Close Resources      $ Mysqli -> Close (); ?>

3. Encapsulation

<? Class  Sqlhelper {  Private   $ Mysqli  ; //  Write to death first, and then use a file for configuration.          Private   Static   $ Host = "Localhost" ;  Private   Static   $ User = "Root" ;  Private   Static   $ Pwd = "Root" ;  Private  Static   $ DB = "Test" ;  Public   Function  _ Construct (){  $ This -> Mysqli = New Mysqli (SELF :: $ Host , Self :: $ User , Self :: $ Pwd , Self :: $ DB  );  If ($ This -> Mysqli-> Connect_error ){  Die ("Connection failed ". $ This -> Mysqli-> Connect_error );}  //  Set Character Set              $ This -> Mysqli-> query ("set names utf8" );}  //  Dql operate          Function Execute_dql ( $ SQL ){  $ Res = $ This -> Mysqli-> query ( $ SQL ) Or Die ( $ This -> Mysqli-> Error );  Return   $ Res  ;}  //  DML operate          Function Execute_dml ( $ SQL ){  $ Res = $ This -> Mysqli-> query ( $ SQL ) Or Die ( $ This -> Mysqli-> Error );  If (! $ Res  ){  Return 0; //  Failed }Else  {  If ( $ This -> Mysqli-> affected_rows> 0 ){  Return 1; //  Successful } Else  {  Return 2; //  No line impact  }}}} ?>