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PDO method in php to implement database addition, deletion, modification and query_PHP tutorial

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WBOYOriginal
2016-07-13 09:53:56840browse

The PDO method in php realizes the addition, deletion, modification and query of the database

PDO is a public class for mysql database operation. We can directly use pdo to operate without customizing the class. The database is installed, but pdo is not enabled in the default configuration of php, so we must enable it in php.ini before it can be used.

You need to enable php’s pdo support, which is supported by php5.1 or above

There are three elements to achieve database connection singleton: static variables, static instantiation methods, and private constructors DPDO.php

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class DPDO{

private $DSN;

private $DBUser;

private $DBPwd;

private $longLink;

private $pdo;

//私有构造函数 防止被直接实例化

private function __construct($dsn, $DBUser, $DBPwd, $longLink = false) {

$this->DSN = $dsn;

$this->DBUser = $DBUser;

$this->DBPwd = $DBPwd;

$this->longLink = $longLink;

$this->connect();

}

//私有 空克隆函数 防止被克隆

private function __clone(){}

//静态 实例化函数 返回一个pdo对象

static public function instance($dsn, $DBUser, $DBPwd, $longLink = false){

static $singleton = array();//静态函数 用于存储实例化对象

$singIndex = md5($dsn . $DBUser . $DBPwd . $longLink);

if (empty($singleton[$singIndex])) {

$singleton[$singIndex] = new self($dsn, $DBUser, $DBPwd, $longLink = false);

}

return $singleton[$singIndex]->pdo;

}

 

private function connect(){

try{

if($this->longLink){

$this->pdo = new PDO($this->DSN, $this->DBUser, $this->DBPwd, array(PDO::ATTR_PERSISTENT => true));

}else{

$this->pdo = new PDO($this->DSN, $this->DBUser, $this->DBPwd);

}

$this->pdo->query('SET NAMES UTF-8');

} catch(PDOException $e) {

die('Error:' . $e->getMessage() . '
');

}

}

}

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class DPDO{ private $DSN; private $DBUser; private $DBPwd; private $longLink; private $pdo; //Private constructor to prevent direct instantiation private function __construct($dsn, $DBUser, $DBPwd, $longLink = false) { $this->DSN = $dsn; $this->DBUser = $DBUser; $this->DBPwd = $DBPwd; $this->longLink = $longLink; $this->connect(); } //Private empty clone function to prevent being cloned private function __clone(){} //Static instantiation function returns a pdo object static public function instance($dsn, $DBUser, $DBPwd, $longLink = false){ static $singleton = array();//static function used to store instantiated objects $singIndex = md5($dsn . $DBUser . $DBPwd . $longLink); if (empty($singleton[$singIndex])) { $singleton[$singIndex] = new self($dsn, $DBUser, $DBPwd, $longLink = false); } return $singleton[$singIndex]->pdo; } private function connect(){ try{ if($this->longLink){ $this->pdo = new PDO($this->DSN, $this->DBUser, $this->DBPwd, array(PDO::ATTR_PERSISTENT => true)); }else{ $this->pdo = new PDO($this->DSN, $this->DBUser, $this->DBPwd); } $this->pdo->query('SET NAMES UTF-8'); } catch(PDOException $e) { die('Error:' . $e->getMessage() . '
'); } } }

Used to handle field mapping. Using pdo field mapping can effectively avoid sql injection

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//字段关联数组处理, 主要用于写入和更新数据、同and 或 or 的查询条件,产生sql语句和映射字段的数组

public function FDFields($data, $link = ',', $judge = array(), $aliasTable = ''){

$sql = '';

$mapData = array();

foreach($data as $key => $value) {

$mapIndex = ':' . ($link != ',' ? 'c' : '') . $aliasTable . $key;

$sql .= ' ' . ($aliasTable ? $aliasTable . '.' : '') . '`' . $key . '` ' . ($judge[$key] ? $judge[$key] : '=') . ' ' . $mapIndex . ' ' . $link;

$mapData[$mapIndex] = $value;

}

$sql = trim($sql, $link);

return array($sql, $mapData);

}

//用于处理单个字段处理

public function FDField($field, $value, $judge = '=', $preMap = 'cn', $aliasTable = '') {

$mapIndex = ':' . $preMap . $aliasTable . $field;

$sql = ' ' . ($aliasTable ? $aliasTable . '.' : '') . '`' . $field . '`' . $judge . $mapIndex;

$mapData[$mapIndex] = $value;

return array($sql, $mapData);

}

//使用刚方法可以便捷产生查询条件及对应数据数组

public function FDCondition($condition, $mapData) {

if(is_string($condition)) {

$where = $condition;

} else if (is_array($condition)) {

if($condition['str']) {

if (is_string($condition['str'])) {

$where = $condition['str'];

} else {

return false;

}

}

if(is_array($condition['data'])) {

$link = $condition['link'] ? $condition['link'] : 'and';

list($conSql, $mapConData) = $this->FDFields($condition['data'], $link, $condition['judge']);

if ($conSql) {

$where .= ($where ? ' ' . $link : '') . $conSql;

$mapData = array_merge($mapData, $mapConData);

}

}

}

return array($where, $mapData);

}

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//Field associative array processing, mainly used for writing and updating data, query conditions with the same and or or, and generating sql statements and arrays of mapped fields public function FDFields($data, $link = ',', $judge = array(), $aliasTable = ''){ $sql = ''; $mapData = array(); foreach($data as $key => $value) { $mapIndex = ':' . ($link != ',' ? 'c' : '') . $aliasTable . $key; $sql .= ' ' . ($aliasTable ? $aliasTable . '.' : '') . '`' . $key . '` ' . ($judge[$key] ? $judge[$key] : '=') . ' ' . $mapIndex . ' ' . $link; $mapData[$mapIndex] = $value; } $sql = trim($sql, $link); return array($sql, $mapData); } //Used to handle single field processing public function FDField($field, $value, $judge = '=', $preMap = 'cn', $aliasTable = '') { $mapIndex = ':' . $preMap . $aliasTable . $field; $sql = ' ' . ($aliasTable ? $aliasTable . '.' : '') . '`' . $field . '`' . $judge . $mapIndex; $mapData[$mapIndex] = $value; return array($sql, $mapData); } //Using the Gang method can easily generate query conditions and corresponding data arrays public function FDCondition($condition, $mapData) { if(is_string($condition)) { $where = $condition; } else if (is_array($condition)) { if($condition['str']) { if (is_string($condition['str'])) { $where = $condition['str']; } else { return false; } } if(is_array($condition['data'])) { $link = $condition['link'] ? $condition['link'] : 'and'; list($conSql, $mapConData) = $this->FDFields($condition['data'], $link, $condition['judge']); if ($conSql) { $where .= ($where ? ' ' . $link : '') . $conSql; $mapData = array_merge($mapData, $mapConData); } } } return array($where, $mapData); }

Specific implementation of addition, deletion, modification and query DB.php

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public function fetch($sql, $searchData = array(), $dataMode = PDO::FETCH_ASSOC, $preType = array(PDO::ATTR_CURSOR => PDO::CURSOR_FWDONLY)) {

if ($sql) {

$sql .= ' limit 1';

$pdoStatement = $this->pdo->prepare($sql, $preType);

$pdoStatement->execute($searchData);

return $data = $pdoStatement->fetch($dataMode);

} else {

return false;

}

}

public function fetchAll($sql, $searchData = array(), $limit = array(0, 10), $dataMode = PDO::FETCH_ASSOC, $preType = array(PDO::ATTR_CURSOR => PDO:: CURSOR_FWDONLY)) {

if ($sql) {

$sql .= ' limit ' . (int) $limit[0] . ',' . (intval($limit[1]) > 0 ? intval($limit[1]) : 10);

$pdoStatement = $this->pdo->prepare($sql, $preType);

$pdoStatement->execute($searchData);

return $data = $pdoStatement->fetchAll($dataMode);

} else {

return false;

}

}

public function insert($tableName, $data, $returnInsertId = false, $replace = false) {

if(!empty($tableName) && count($data) > 0){

$sql = $replace ? 'REPLACE INTO ' : 'INSERT INTO ';

list($setSql, $mapData) = $this->FDFields($data);

$sql .= $tableName . ' set ' . $setSql;

$pdoStatement = $this->pdo->prepare($sql, array(PDO::ATTR_CURSOR => PDO::CURSOR_FWDONLY));

$execRet = $pdoStatement->execute($mapData);

return $execRet ? ($returnInsertId ? $this->pdo->lastInsertId() : $execRet) : false;

} else {

return false;

}

}

public function update($tableName, $data, $condition, $mapData = array(), $returnRowCount = true) {

if(!empty($tableName) && count($data) > 0) {

$sql = 'UPDATE ' . $tableName . ' SET ';

list($setSql, $mapSetData) = $this->FDFields($data);

$sql .= $setSql;

$mapData = array_merge($mapData, $mapSetData);

list($where, $mapData) = $this->FDCondition($condition, $mapData);

$sql .= $where ? ' WHERE ' . $where : '';

$pdoStatement = $this->pdo->prepare($sql, array(PDO::ATTR_CURSOR => PDO::CURSOR_FWDONLY));

$execRet = $pdoStatement->execute($mapData);

return $execRet ? ($returnRowCount ? $pdoStatement->rowCount() : $execRet) : false;

} else {

return false;

}

}

public function delete($tableName, $condition, $mapData = array()) {

if(!empty($tableName) && $condition){

$sql = 'DELETE FROM ' . $tableName;

list($where, $mapData) = $this->FDCondition($condition, $mapData);

$sql .= $where ? ' WHERE ' . $where : '';

$pdoStatement = $this->pdo->prepare($sql, array(PDO::ATTR_CURSOR => PDO::CURSOR_FWDONLY));

$execRet = $pdoStatement->execute($mapData);

return $execRet;

}

}

  测试文件test.php

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header("Content-type: text/html; charset=utf-8");

define('APP_DIR', dirname(__FILE__));

 

if (function_exists('spl_autoload_register')) {

spl_autoload_register('autoClass');

} else {

function __auto_load($className){

autoClass($className);

}

}

 

function autoClass($className){

try{

require_once APP_DIR.'/class/'.$className.'.php';

} catch (Exception $e) {

die('Error:' . $e->getMessage() . '
');

}

}

$DB = new DB();

//插入

$inData['a'] = rand(1, 100);

$inData['b'] = rand(1, 1000);

$inData['c'] = rand(1,200) . '.' . rand(1,100);

$ret = $DB->insert('a', $inData);

echo '插入' . ($ret ? '成功' : '失败') . '
';

//更新

$upConData['a'] = 100;

$upConJudge['a'] = '<';

$upConData['b'] = 30;

$upConJudge['b'] = '>';

list($upConStr, $mapUpConData) = $DB->FDField('b', 200, '<', 'gt');

$condition = array(

'str' => $upConStr,

'data' => $upConData,

'judge' => $upConJudge,

'link' => 'and'

);

$upData['a'] = rand(1, 10);

$upData['b'] = 1;

$upData['c'] = 1.00;

$changeRows = $DB->update('a', $upData, $condition, $mapUpConData);

echo '更新行数:' . (int) $changeRows . '
';

//删除

$delVal = rand(1, 10);

list($delCon, $mapDelCon) = $DB->FDField('a', $delVal);

$delRet = $DB->delete('a', $delCon, $mapDelCon);

echo '删除a=' . $delVal . ($delRet ? '成功' : '失败') . '
';

 

//查询

$data['a'] = '10';

$judge['a'] = '>';

$data['b'] = '400';

$judge['b'] = '<';

list($conSql, $mapConData) = $DB->FDFields($data, 'and', $judge);

$mData = $DB->fetch('select * from a where ' . $conSql . ' order by `a` desc', $mapConData);

 

var_dump($mData);

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header("Content-type: text/html; charset=utf-8"); define('APP_DIR', dirname(__FILE__));   if (function_exists('spl_autoload_register')) { spl_autoload_register('autoClass'); } else { function __auto_load($className){ autoClass($className); } }   function autoClass($className){ try{ require_once APP_DIR.'/class/'.$className.'.php'; } catch (Exception $e) { die('Error:' . $e->getMessage() . '
'); } } $DB = new DB(); //插入 $inData['a'] = rand(1, 100); $inData['b'] = rand(1, 1000); $inData['c'] = rand(1,200) . '.' . rand(1,100); $ret = $DB->insert('a', $inData); echo '插入' . ($ret ? '成功' : '失败') . '
'; //更新 $upConData['a'] = 100; $upConJudge['a'] = '<';<🎜> <🎜>$upConData['b'] = 30;<🎜> <🎜>$upConJudge['b'] = '>'; list($upConStr, $mapUpConData) = $DB->FDField('b', 200, '<', 'gt');<🎜> <🎜>$condition = array(<🎜> <🎜>'str' => $upConStr, 'data' => $upConData, 'judge' => $upConJudge, 'link' => 'and' ); $upData['a'] = rand(1, 10); $upData['b'] = 1; $upData['c'] = 1.00; $changeRows = $DB->update('a', $upData, $condition, $mapUpConData); echo '更新行数:' . (int) $changeRows . '
'; //删除 $delVal = rand(1, 10); list($delCon, $mapDelCon) = $DB->FDField('a', $delVal); $delRet = $DB->delete('a', $delCon, $mapDelCon); echo '删除a=' . $delVal . ($delRet ? '成功' : '失败') . '
';   //查询 $data['a'] = '10'; $judge['a'] = '>'; $data['b'] = '400'; $judge['b'] = '<';<🎜> <🎜>list($conSql, $mapConData) = $DB->FDFields($data, 'and', $judge); $mData = $DB->fetch('select * from a where ' . $conSql . ' order by `a` desc', $mapConData);   var_dump($mData);

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