Medoo是一款轻量级的php数据库操作类,下面不会介绍Medoo的使用方法,想学习Medoo请前往官网自学:http://medoo.in/

  在接触Medoo之前,一直是用自己写的php数据库操作类,而发现Medoo立马就喜欢上了它,但是对它的调试方式不喜欢。

  Medoo提供两种调试,分别是:

  error()

$database = new medoo("my_database");

$database->select("bccount", [
"user_name",
"email"
], [
"user_id[<]" => 20
]); var_dump($database->error()); // array(3) { [0]=> string(5) "42S02" [1]=> int(1146) [2]=> string(36) "Table 'my_database.bccount' doesn't exist" }

  last_query()

$database = new medoo("my_database");

$database->select("account", [
"user_name",
"email"
], [
"user_id[<]" => 20
]); echo $database->last_query();
// SELECT user_name, email FROM account WHERE user_id < 20

  对于last_query()的使用我个人挺不习惯的,首先使用太麻烦,我坚决认为调试输出报错信息或者sql语句的操作一定要简单便捷,不要为了输出一句sql语句还要写一行代码,这样很容易打断我的思路。

  所以我对Medoo的每一个query方法都增加了一个对应调试方法,就是在方法名前增加一个“_”,比如最常见的select方法:

$database = new medoo("my_database");

$database->_select("account", [
"user_name",
"email"
], [
"user_id[<]" => 20
]);
// SELECT user_name, email FROM account WHERE user_id < 20

  同样其它的insert、update、delete、replace、get、has、count、max、min、avg、sum方法也都可以用这样方式快速输出sql语句。

  当然我新增的这种调试方式,也不会影响Medoo原有的两种调试方式。

  下面就是修改版源码了,基于Medoo 0.9.1.1修改

<?php
/*!
* Medoo database framework
* http://medoo.in
* Version 0.9.1.1
*
* Copyright 2013, Angel Lai
* Released under the MIT license
*
* @代码小睿 修改如下:
* 增加PDO事务
* query exec select insert update delete replace get has count max min avg sum 方法各增加直接输出 sql 语句的方法
* 如 select 则对应 _select 方法
*/
class medoo{
protected $database_type = 'mysql'; // For MySQL, MSSQL, Sybase
protected $server = 'localhost';
protected $username = 'username';
protected $password = 'password'; // For SQLite
protected $database_file = ''; // Optional
protected $port = 3306;
protected $charset = 'utf8';
protected $database_name = '';
protected $option = array(); // Variable
protected $queryString; // Debug
protected $debug = false; public function __construct($options){
try{
$commands = array();
if(is_string($options)){
if(strtolower($this->database_type) == 'sqlite'){
$this->database_file = $options;
}else{
$this->database_name = $options;
}
}else{
foreach($options as $option => $value){
$this->$option = $value;
}
}
$type = strtolower($this->database_type);
if(isset($this->port) && is_int($this->port * 1)){
$port = $this->port;
}
$set_charset = "SET NAMES '" . $this->charset . "'";
switch($type){
case 'mariadb':
$type = 'mysql';
case 'mysql':
// Make MySQL using standard quoted identifier
$commands[] = 'SET SQL_MODE=ANSI_QUOTES';
case 'pgsql':
$dsn = $type . ':host=' . $this->server . (isset($port) ? ';port=' . $port : '') . ';dbname=' . $this->database_name;
$commands[] = $set_charset;
break;
case 'sybase':
$dsn = $type . ':host=' . $this->server . (isset($port) ? ',' . $port : '') . ';dbname=' . $this->database_name;
$commands[] = $set_charset;
break;
case 'mssql':
$dsn = strpos(PHP_OS, 'WIN') !== false ?
'sqlsrv:server=' . $this->server . (isset($port) ? ',' . $port : '') . ';database=' . $this->database_name :
'dblib:host=' . $this->server . (isset($port) ? ':' . $port : '') . ';dbname=' . $this->database_name;
// Keep MSSQL QUOTED_IDENTIFIER is ON for standard quoting
$commands[] = 'SET QUOTED_IDENTIFIER ON';
$commands[] = $set_charset;
break;
case 'sqlite':
$dsn = $type . ':' . $this->database_file;
$this->username = null;
$this->password = null;
break;
}
$this->pdo = new PDO(
$dsn,
$this->username,
$this->password,
$this->option
);
foreach($commands as $value){
$this->pdo->exec($value);
}
}catch(PDOException $e){
throw new Exception($e->getMessage());
}
} public function beginTransaction(){
$this->pdo->beginTransaction();
}
public function commit(){
$this->pdo->commit();
}
public function rollBack(){
$this->pdo->rollBack();
} public function query($query){
$this->queryString = $query;
return $this->debug ? $query : $this->pdo->query($query);
}
public function _query($query){
$this->debug = true;
echo $this->query($query);
} public function exec($query){
$this->queryString = $query;
return $this->debug ? $query : $this->pdo->exec($query);
}
public function _exec($query){
$this->debug = true;
echo $this->exec($query);
} public function quote($string){
return $this->pdo->quote($string);
} protected function column_quote($string){
return '"' . str_replace('.', '"."', $string) . '"';
} protected function column_push($columns){
if($columns == '*'){
return $columns;
}
if(is_string($columns)){
$columns = array($columns);
}
$stack = array();
foreach($columns as $key => $value){
preg_match('/([a-zA-Z0-9_\-\.]*)\s*\(([a-zA-Z0-9_\-]*)\)/i', $value, $match);
if(isset($match[1]) && isset($match[2])){
array_push($stack, $this->column_quote( $match[1] ) . ' AS ' . $this->column_quote( $match[2] ));
}else{
array_push($stack, $this->column_quote( $value ));
}
}
return implode($stack, ',');
} protected function array_quote($array){
$temp = array();
foreach($array as $value){
$temp[] = is_int($value) ? $value : $this->pdo->quote($value);
}
return implode($temp, ',');
} protected function inner_conjunct($data, $conjunctor, $outer_conjunctor){
$haystack = array();
foreach($data as $value){
$haystack[] = '(' . $this->data_implode($value, $conjunctor) . ')';
}
return implode($outer_conjunctor . ' ', $haystack);
} protected function data_implode($data, $conjunctor, $outer_conjunctor = null){
$wheres = array();
foreach($data as $key => $value){
if(($key == 'AND' || $key == 'OR') && is_array($value)){
$wheres[] = 0 !== count(array_diff_key($value, array_keys(array_keys($value)))) ?
'(' . $this->data_implode($value, ' ' . $key) . ')' :
'(' . $this->inner_conjunct($value, ' ' . $key, $conjunctor) . ')';
}else{
preg_match('/([\w\.]+)(\[(\>|\>\=|\<|\<\=|\!|\<\>)\])?/i', $key, $match);
if(isset($match[3])){
if($match[3] == ''){
$wheres[] = $this->column_quote($match[1]) . ' ' . $match[3] . '= ' . $this->quote($value);
}else if($match[3] == '!'){
$column = $this->column_quote($match[1]);
switch(gettype($value)){
case 'NULL':
$wheres[] = $column . ' IS NOT NULL';
break;
case 'array':
$wheres[] = $column . ' NOT IN (' . $this->array_quote($value) . ')';
break;
case 'integer':
case 'double':
$wheres[] = $column . ' != ' . $value;
break;
case 'string':
$wheres[] = $column . ' != ' . $this->quote($value);
break;
}
}else{
if($match[3] == '<>'){
if(is_array($value)){
if(is_numeric($value[0]) && is_numeric($value[1])){
$wheres[] = $this->column_quote($match[1]) . ' BETWEEN ' . $value[0] . ' AND ' . $value[1];
}else{
$wheres[] = $this->column_quote($match[1]) . ' BETWEEN ' . $this->quote($value[0]) . ' AND ' . $this->quote($value[1]);
}
}
}else{
if(is_numeric($value)){
$wheres[] = $this->column_quote($match[1]) . ' ' . $match[3] . ' ' . $value;
}else{
$datetime = strtotime($value);
if($datetime){
$wheres[] = $this->column_quote($match[1]) . ' ' . $match[3] . ' ' . $this->quote(date('Y-m-d H:i:s', $datetime));
}
}
}
}
}else{
if(is_int($key)){
$wheres[] = $this->quote($value);
}else{
$column = $this->column_quote($match[1]);
switch(gettype($value)){
case 'NULL':
$wheres[] = $column . ' IS NULL';
break;
case 'array':
$wheres[] = $column . ' IN (' . $this->array_quote($value) . ')';
break;
case 'integer':
case 'double':
$wheres[] = $column . ' = ' . $value;
break;
case 'string':
$wheres[] = $column . ' = ' . $this->quote($value);
break;
}
}
}
}
}
return implode($conjunctor . ' ', $wheres);
} public function where_clause($where){
$where_clause = '';
if(is_array($where)){
$single_condition = array_diff_key($where, array_flip(
explode(' ', 'AND OR GROUP ORDER HAVING LIMIT LIKE MATCH')
));
if($single_condition != array()){
$where_clause = ' WHERE ' . $this->data_implode($single_condition, '');
}
if(isset($where['AND'])){
$where_clause = ' WHERE ' . $this->data_implode($where['AND'], ' AND');
}
if(isset($where['OR'])){
$where_clause = ' WHERE ' . $this->data_implode($where['OR'], ' OR');
}
if(isset($where['LIKE'])){
$like_query = $where['LIKE'];
if(is_array($like_query)){
$is_OR = isset($like_query['OR']);
if($is_OR || isset($like_query['AND'])){
$connector = $is_OR ? 'OR' : 'AND';
$like_query = $is_OR ? $like_query['OR'] : $like_query['AND'];
}else{
$connector = 'AND';
}
$clause_wrap = array();
foreach($like_query as $column => $keyword){
if(is_array($keyword)){
foreach($keyword as $key){
$clause_wrap[] = $this->column_quote($column) . ' LIKE ' . $this->quote('%' . $key . '%');
}
}else{
$clause_wrap[] = $this->column_quote($column) . ' LIKE ' . $this->quote('%' . $keyword . '%');
}
}
$where_clause .= ($where_clause != '' ? ' AND ' : ' WHERE ') . '(' . implode($clause_wrap, ' ' . $connector . ' ') . ')';
}
}
if(isset($where['MATCH'])){
$match_query = $where['MATCH'];
if(is_array($match_query) && isset($match_query['columns']) && isset($match_query['keyword'])){
$where_clause .= ($where_clause != '' ? ' AND ' : ' WHERE ') . ' MATCH ("' . str_replace('.', '"."', implode($match_query['columns'], '", "')) . '") AGAINST (' . $this->quote($match_query['keyword']) . ')';
}
}
if(isset($where['GROUP'])){
$where_clause .= ' GROUP BY ' . $this->column_quote($where['GROUP']);
}
if(isset($where['ORDER'])){
preg_match('/(^[a-zA-Z0-9_\-\.]*)(\s*(DESC|ASC))?/', $where['ORDER'], $order_match);
$where_clause .= ' ORDER BY "' . str_replace('.', '"."', $order_match[1]) . '" ' . (isset($order_match[3]) ? $order_match[3] : '');
if(isset($where['HAVING'])){
$where_clause .= ' HAVING ' . $this->data_implode($where['HAVING'], '');
}
}
if(isset($where['LIMIT'])){
if(is_numeric($where['LIMIT'])){
$where_clause .= ' LIMIT ' . $where['LIMIT'];
}
if(is_array($where['LIMIT']) && is_numeric($where['LIMIT'][0]) && is_numeric($where['LIMIT'][1])){
$where_clause .= ' LIMIT ' . $where['LIMIT'][0] . ',' . $where['LIMIT'][1];
}
}
}else{
if($where != null){
$where_clause .= ' ' . $where;
}
}
return $where_clause;
} public function select($table, $join, $columns = null, $where = null){
$table = '"' . $table . '"';
$join_key = is_array($join) ? array_keys($join) : null;
if(strpos($join_key[0], '[') !== false){
$table_join = array();
$join_array = array(
'>' => 'LEFT',
'<' => 'RIGHT',
'<>' => 'FULL',
'><' => 'INNER'
);
foreach($join as $sub_table => $relation){
preg_match('/(\[(\<|\>|\>\<|\<\>)\])?([a-zA-Z0-9_\-]*)/', $sub_table, $match);
if($match[2] != '' && $match[3] != ''){
if(is_string($relation)){
$relation = 'USING ("' . $relation . '")';
}
if(is_array($relation)){
if(isset($relation[0])){ // For ['column1', 'column2']
$relation = 'USING ("' . implode($relation, '", "') . '")';
}else{ // For ['column1' => 'column2']
$relation = 'ON ' . $table . '."' . key($relation) . '" = "' . $match[3] . '"."' . current($relation) . '"';
}
}
$table_join[] = $join_array[ $match[2] ] . ' JOIN "' . $match[3] . '" ' . $relation;
}
}
$table .= ' ' . implode($table_join, ' ');
}else{
$where = $columns;
$columns = $join;
}
$query = $this->query('SELECT ' . $this->column_push($columns) . ' FROM ' . $table . $this->where_clause($where));
return is_string($query) ? $query : ($query ? $query->fetchAll((is_string($columns) && $columns != '*') ? PDO::FETCH_COLUMN : PDO::FETCH_ASSOC) : false);
}
public function _select($table, $join, $columns = null, $where = null){
$this->debug = true;
echo $this->select($table, $join, $columns, $where);
} public function insert($table, $datas){
$lastId = array();
$query = array();
// Check indexed or associative array
if(!isset($datas[0])){
$datas = array($datas);
}
foreach($datas as $data){
$keys = implode('", "', array_keys($data));
$values = array();
foreach($data as $key => $value){
switch(gettype($value)){
case 'NULL':
$values[] = 'NULL';
break;
case 'array':
$values[] = $this->quote(serialize($value));
break;
case 'integer':
case 'double':
case 'string':
$values[] = $this->quote($value);
break;
}
}
$exec = $this->exec('INSERT INTO "' . $table . '" ("' . $keys . '") VALUES (' . implode($values, ', ') . ')');
is_string($exec) ? $query[] = $exec : $lastId[] = $this->pdo->lastInsertId();
}
return $query ? implode('; ', $query) : (count($lastId) > 1 ? $lastId : $lastId[0]);
}
public function _insert($table, $datas){
$this->debug = true;
echo $this->insert($table, $datas);
} public function update($table, $data, $where = null){
$fields = array();
foreach($data as $key => $value){
if(is_array($value)){
$fields[] = $this->column_quote($key) . '=' . $this->quote(serialize($value));
}else{
preg_match('/([\w]+)(\[(\+|\-|\*|\/)\])?/i', $key, $match);
if(isset($match[3])){
if(is_numeric($value)){
$fields[] = $this->column_quote($match[1]) . ' = ' . $this->column_quote($match[1]) . ' ' . $match[3] . ' ' . $value;
}
}else{
$column = $this->column_quote($key);
switch(gettype($value)){
case 'NULL':
$fields[] = $column . ' = NULL';
break;
case 'array':
$fields[] = $column . ' = ' . $this->quote(serialize($value));
break;
case 'integer':
case 'double':
case 'string':
$fields[] = $column . ' = ' . $this->quote($value);
break;
}
}
}
}
return $this->exec('UPDATE "' . $table . '" SET ' . implode(', ', $fields) . $this->where_clause($where));
}
public function _update($table, $data, $where = null){
$this->debug = true;
echo $this->update($table, $data, $where);
} public function delete($table, $where){
return $this->exec('DELETE FROM "' . $table . '"' . $this->where_clause($where));
}
public function _delete($table, $where){
$this->debug = true;
echo $this->delete($table, $where);
} public function replace($table, $columns, $search = null, $replace = null, $where = null){
if(is_array($columns)){
$replace_query = array();
foreach($columns as $column => $replacements){
foreach($replacements as $replace_search => $replace_replacement){
$replace_query[] = $column . ' = REPLACE("' . $column . '", ' . $this->quote($replace_search) . ', ' . $this->quote($replace_replacement) . ')';
}
}
$replace_query = implode(', ', $replace_query);
$where = $search;
}else{
if(is_array($search)){
$replace_query = array();
foreach($search as $replace_search => $replace_replacement){
$replace_query[] = $columns . ' = REPLACE("' . $columns . '", ' . $this->quote($replace_search) . ', ' . $this->quote($replace_replacement) . ')';
}
$replace_query = implode(', ', $replace_query);
$where = $replace;
}else{
$replace_query = $columns . ' = REPLACE("' . $columns . '", ' . $this->quote($search) . ', ' . $this->quote($replace) . ')';
}
}
return $this->exec('UPDATE "' . $table . '" SET ' . $replace_query . $this->where_clause($where));
}
public function _replace($table, $columns, $search = null, $replace = null, $where = null){
$this->debug = true;
echo $this->replace($table, $columns, $search, $replace, $where);
} public function get($table, $columns, $where = null){
if(!isset($where)){
$where = array();
}
$where['LIMIT'] = 1;
$data = $this->select($table, $columns, $where);
return is_string($data) ? $data : (isset($data[0]) ? $data[0] : false);
}
public function _get($table, $columns, $where = null){
$this->debug = true;
echo $this->get($table, $columns, $where);
} public function has($table, $where){
$query = $this->query('SELECT EXISTS(SELECT 1 FROM "' . $table . '"' . $this->where_clause($where) . ')');
return is_string($query) ? $query : $query->fetchColumn() === '1';
}
public function _has($table, $where){
$this->debug = true;
echo $this->has($table, $where);
} public function count($table, $where = null){
$query = $this->query('SELECT COUNT(*) FROM "' . $table . '"' . $this->where_clause($where));
return is_string($query) ? $query : 0 + ($query->fetchColumn());
}
public function _count($table, $where = null){
$this->debug = true;
echo $this->count($table, $where);
} public function max($table, $column, $where = null){
$query = $this->query('SELECT MAX("' . $column . '") FROM "' . $table . '"' . $this->where_clause($where));
return is_string($query) ? $query : 0 + ($query->fetchColumn());
}
public function _max($table, $column, $where = null){
$this->debug = true;
echo $this->max($table, $column, $where);
} public function min($table, $column, $where = null){
$query = $this->query('SELECT MIN("' . $column . '") FROM "' . $table . '"' . $this->where_clause($where));
return is_string($query) ? $query : 0 + ($query->fetchColumn());
}
public function _min($table, $column, $where = null){
$this->debug = true;
echo $this->min($table, $column, $where);
} public function avg($table, $column, $where = null){
$query = $this->query('SELECT AVG("' . $column . '") FROM "' . $table . '"' . $this->where_clause($where));
return is_string($query) ? $query : 0 + ($query->fetchColumn());
}
public function _avg($table, $column, $where = null){
$this->debug = true;
echo $this->avg($table, $column, $where);
} public function sum($table, $column, $where = null){
$query = $this->query('SELECT SUM("' . $column . '") FROM "' . $table . '"' . $this->where_clause($where));
return is_string($query) ? $query : 0 + ($query->fetchColumn());
}
public function _sum($table, $column, $where = null){
$this->debug = true;
echo $this->sum($table, $column, $where);
} public function error(){
return $this->pdo->errorInfo();
} public function last_query(){
return $this->queryString;
} public function info(){
return array(
'server' => $this->pdo->getAttribute(PDO::ATTR_SERVER_INFO),
'client' => $this->pdo->getAttribute(PDO::ATTR_CLIENT_VERSION),
'driver' => $this->pdo->getAttribute(PDO::ATTR_DRIVER_NAME),
'version' => $this->pdo->getAttribute(PDO::ATTR_SERVER_VERSION),
'connection' => $this->pdo->getAttribute(PDO::ATTR_CONNECTION_STATUS)
);
}
}
?>

  

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