The basic operation of PDO for MySQL

PDO expansion Operations<?PHP$dsn= ' Mysql:dbname=yii2;host=localhost ';$user= ' Root ';$password= ' 123456 ';Try{    $DBH=NewPDO ($dsn,$user,$password,Array(Pdo::attr_errmode = PDO::errmode_exception));}Catch(pdoexception$e){    Echo' Connection failed: '.$e-getMessage ();}//Transaction Usage-begintransaction (), Commit (), RollBack (), exec ()/*//Added the last parameter in New PDO () try{$dbh->begintransaction ();    $sqlDel = "Delete from country where code = ' PK '";    $sqlIn = "INSERT INTO country (CODE,NAME,POP) VALUES (' TT ', ' TEST ', 9999)";    $DBH->exec ($sqlDel);    $DBH->exec ($sqlIn); $DBH->commit ();}    catch (Pdoexception $e) {echo "<br/>error:<br/>";    echo "<pre>";    Print_r ($e->getmessage ()); $DBH->rollback ();}*///Transaction Use-SetAttribute (), BeginTransaction (), Commit (), RollBack ()/*//Set the error mode, be sure to set it, otherwise it will not roll back and throw an exception, or you can add this value to the last parameter of the new PDO ($dbh->setattribute) (Pdo::attr_errmode,pdo::errmode_     EXCEPTION); try{$dbh->begintransaction ();     $sqlDel = "Delete from country where code = ' GX '";     $sqlIn = "INSERT INTO country (code,name,population) VALUES (' PK ', ' good ', ' 4444444 ')";     $delFlag = $dbh->exec ($sqlDel);     $inFlag = $dbh->exec ($sqlIn);     Var_dump ($delFlag);     Var_dump ($inFlag);    Echo ' Commit '; Var_dump ($DBH->intransaction ());         True $DBH->commit ();    Var_dump ($DBH->lastinsertid ()); Echo ' commit222222 ';}    catch (Pdoexception $e) {echo ' rollBack ';    $DBH->rollback (); echo $e->getmessage ();} $DBH->setattribute (pdo::attr_autocommit,1);*///Delete-exec ()/*$sql = "Delete from country where code = ' FK '"; $count = $dbh->exec ($sql); Var_dump ($count);//int (1) int (0)*///New-exec ()/*$sql = "INSERT INTO country (code,name,population) VALUES (' FK ', ' yes ', 13000)", $count = $dbh->exec ($sql); var_dump ($count); Int (1)*///queries-query ()/*$sql = "SELECT * from country where code = ' AU '"; $res = $dbh->query ($sql, Pdo::fetch_assoc); foreach ($res as $row) {    echo "<pre>"; Print_r ($row);} Array ([Code] = AU [name] = Australia [Population] = 18886000)*///Query-fetchall ()/*$sql = "SELECT * from country where code =: Code"; $sth = $dbh->prepare ($sql); $sth->execute (Array (": Code" = "A U ")); $res = $sth->fetchall (PDO::FETCH_ASSOC); can also be used in $DBH->setattribute (PDO::ATTR_DEFAULT_FETCH_MODE,PDO::FETCH_ASSOC), set only associative array print_r ($res);*//*Array ([0] = = Array ([code] = au [0] = = au [name] = = Australi A [1] = Australia [Population] = 18886000 [2] = 18886000)) Array ([ 0] = = Array ([code] + AU [name] + Australia [population] = 1888600 0))*///pdostatement Operation<?php//http://php.net/manual/zh/pdostatement.execute.php$dsn= ' Mysql:host=localhost;dbname=yii2 ';$username= ' Root ';$password= ' 123456 ';Try{    $DBH=NewPDO ($dsn,$username,$password);}Catch(pdoexception$e){    Echo"Failure:"; Echo $e-GetMessage (); Exit();}Echo"<pre>";/*print a SQL preprocessing command-debugdumpparams$name = ' GD '; $sql = "SELECT * from country WHERE name =: Name"; $res = $dbh->prepare ( $sql) $res->bindvalue (": Name", $name), $res->execute (); $res->debugdumpparams (); $rr = $res->fetchall ( PDO::FETCH_ASSOC);p Rint_r ($RR); SQL: [+] SELECT * FROM country where name =: Nameparams:1key:name: [5]: nameparamno=-1name=[5] ": Name" IS_PARAM=1PARAM_ type=2*//*gets the number of columns of the record ColumnCount () $sql = "SELECT * from country"; $res = $dbh->prepare ($sql); $res->execute (); $RR = $res ColumnCount ();p rint_r ($RR); 3*//*returns the number of rows affected-rowCount (), prepare (), Bindvalue (), execute (), $code = ' PK '; $sql = "Update country set name = ' GD ' where code =: Code "; $res = $dbh->prepare ($sql); $res->bindvalue (": Code ", $code); $res->execute (); $affectCount = $res- >rowcount ();p rint_r ($affectCount); 1*//*Query-Prepare (), Bindvalue (), Fetchall (), execute () $name = ' good '; $sql = "SELECT count (1) as total from country where Nam E =: Name "; $res = $dbh->prepare ($sql); $res->bindvalue (": Name ", $name); $res->execute (); $RR = $res Fetchall (PDO::FETCH_ASSOC);p rint_r ($RR); Array ([0] = = Array ([total] = 2))*//*Query-Bindvalue (), execute (), fetchall () $name = ' good '; $code = ' FK '; $sql = "SELECT * from country where name =? and code =? Limit 1 "; $res = $dbh->prepare ($sql); $res->bindvalue (1, $name); $res->bindvalue (2, $code); $res->execute () ; $rr = $res->fetchall (PDO::FETCH_ASSOC);p rint_r ($RR); Array ([0] = = Array ([code] = FK [name] + good [population] = 4 444444))*//*Query-Prepare (), Bindvalue (), execute (), fetchall () $name = "good"; $code = ' FK '; $sql = "SELECT * from country where name = : Name and code =: Code Limit 1 "; $res = $dbh->prepare ($sql); $res->bindvalue (": Code ", $code); $res->bindvalue (": Name ", $name), $res->execute (), $RR = $res->fetchall ();p rint_r ($RR);            Array ([0] = = Array ([code] = FK [0] = = FK [name] = = Good [1] = = good [Population] = 4444444 [2] = 4444444))*//*Query-Prepare (), Bindparam (), execute (), fetchall () $name = ' good '; $code = ' PK '; $sql = "SELECT * from country where name = ? and code =? "; $res = $dbh->prepare ($sql); $res->bindparam (1, $name); $res->bindparam (2, $code); $res->execute (); $RR = $ Res->fetchall (PDO::FETCH_ASSOC);p rint_r ($RR); Array ([0] = = Array ([code] = PK [name] + good [population] + 4 444444))*///Query-Prepare (), Bindparam (), execute (), Fetchall ()/*$name = ' good '; $code = ' PK '; $population = 4444444; $sql = "SELECT * from country WHERE name =: Name and code =: Code an D population =:p opulation "; $res = $dbh->prepare ($sql); $res->bindparam (": Code ", $code); $res->bindparam (": Name ", $name, PDO::P aram_str), $res->bindparam (":p opulation ", $population); $res->execute (); $RR = $res Fetchall (PDO::FETCH_ASSOC);p rint_r ($RR); Array ([0] = = Array ([code] = PK [name] + good [population] + 4 444444))*///Query-Prepare (), execute (), Fetch ()/*$sql = "SELECT * FROM Country limit 2", $res = $dbh->prepare ($sql), $res->execute (), while ($rs = $res->fetch (PD O::FETCH_ASSOC)) {Print_r ($rs);} Array ([code] = AU [name] = + Australia [population] = 18886000) array ([code] = BR [name] =&G T Brazil [Population] = 170115000)*///Query-Prepare (), execute (), Fetchall ()/*$sql = "SELECT * FROM country limit 1"; $res = $dbh->prepare ($sql); $res->execute (); $rr = $res->fetchall ();p RI Nt_r ($RR);            Array ([0] = = Array ([code] = au [0] = = au [name] = = Australia [1] = = Australia [Population] = 18886000 [2] = 18886000))*///Query-Prepare (), execute (), Fetchall ()/** $sql = "SELECT * FROM country limit 1"; $sth = $dbh->prepare ($sql); $sth->execute (); $res = $sth->fetchall (PDO :: FETCH_ASSOC); echo "<pre>";p Rint_r ($res); Array ([0] = = Array ([code] = AU [name] = + Australia [population] =& Gt 18886000))*/

The basic operation of PDO for MySQL