PHP PHP - 轻量级数据库和行集类，ActiveRecord样式函数
Posted
tags:
篇首语：本文由小常识网(cha138.com)小编为大家整理，主要介绍了PHP PHP - 轻量级数据库和行集类，ActiveRecord样式函数相关的知识，希望对你有一定的参考价值。
<?php
// DB - simple database wrapper
// The idea behind this database wrapper is to have a simple to use database wrapper that includes some useful
// commands to do some every day tasks.
//
class DB {
// options
public $enableMoreSearch = true; // disable this if any of your field names end with
// _like, _before, _less_than, _after or _greater_than as this may cause problems
// enables __call()s like find_by_name_like('dom') to match Dom, dom or DOM
// variables
public $c = null;
public $db = null;
public $table = null;
public $id = 'id';
private $engine = "mysql";
private $host = "localhost";
private $user = "root";
private $pass = "";
private $q = "";
// private $db = "test";
private $fields = array();
// __construct
// sets up the connection to the mysql server and selects the database
public function __construct($a = null) {
if (is_array($a)) {
$this->host = (isset($a['host'])) ? $a['host'] : $this->host;
$this->user = (isset($a['user'])) ? $a['user'] : $this->host;
$this->pass = (isset($a['pass']) && is_string($a['pass'])) ? $a['pass'] : $this->pass;
$this->database = (isset($a['database'])) ? $a['database'] : $this->database;
$this->table = (isset($a['table'])) ? $a['table'] : $this->table;
} elseif (is_string($a)) {
if (preg_match("/^(mysql):\/\/([^:]+):(.*)@([a-z0-9\-\.]+):?(\d+)?\/([a-z0-9_\-]+)(\/([a-z0-9_\-]+))?\/?$/i", $a, $m)) {
$this->engine = $m[1];
$this->host = $m[4];
$this->user = $m[2];
$this->pass = $m[3];
$this->db = $m[6];
$this->table = isset($m[8]) ? $m[8] : null;
} else {
throw new Exception("DB Error! (Invalid connection details)");
}
}
if (!is_resource($this->c)) {
if ($this->c = $this->_connect()) {
if ($this->_select_db()) {
return $this->c;
} else {
throw new Exception("DB Error! (Could not select database)");
}
} else {
throw new Exception("DB Error! (Cound not connect to server)");
}
}
}
// __destruct
// closes the connection
public function __destruct() {
return @$this->_close();
// the @ is used because PHP shares mysql connections and if more than one
// 'DB' instance is finished with at the same time, the second, third, etc
// will produce errors, as the connection is already closed, the @ hides
// any errors
}
// __call
// magic method to map unbound functions
// used for db->find_all_by_username("dom") etc
public function __call($f, $a) {
if (preg_match("/^find_(all_by|by)_([_a-zA-Z]\w*)$/", $f, $m)) {
if ($m[1] == "by") {
$array = false;
} elseif ($m[1] == "all_by") {
$array = true;
}
if (isset($a[1]) && is_array($a[1]) && isset($a[1]['table'])) {
$t = $a[1]['table'];
} else {
$t = null;
}
$fields = explode("_or_", $m[2]);
if (count($fields) == 1) {
$fields = explode("_and_", $m[2]);
$mode = "AND";
} else {
$mode = "OR";
}
$find = array();
if (count($fields) == count($a[0]) || (!is_array($a[0]) && count($fields) == 1)) {
foreach ($fields as $i => $key) {
if (is_array($a[0])) {
$value = $a[0][$i];
} else {
$value = $a[0];
}
if ($this->enableMoreSearch) {
if (substr(strtolower($key), -5) == '_like') {
$key = substr($key, 0, -5);
$find[$key] = array('mode' => 'LIKE', 'value' => $value);
} elseif (substr(strtolower($key), -13) == '_greater_than') {
$key = substr($key, 0, -13);
$find[$key] = array('mode' => '>', 'value' => $value);
} elseif (substr(strtolower($key), -6) == '_after') {
$key = substr($key, 0, -6);
$find[$key] = array('mode' => '>', 'value' => $value);
} elseif (substr(strtolower($key), -10) == '_less_than') {
$key = substr($key, 0, -10);
$find[$key] = array('mode' => '<', 'value' => $value);
} elseif (substr(strtolower($key), -7) == '_before') {
$key = substr($key, 0, -7);
$find[$key] = array('mode' => '<', 'value' => $value);
} else {
$find[$key] = $value;
}
} else {
$find[$key] = $value;
}
}
} elseif (count($a) == count($fields)) {
foreach ($fields as $i => $key) {
$value = $a[$i];
if ($this->enableMoreSearch) {
if (substr(strtolower($key), -5) == '_like') {
$key = substr($key, 0, -5);
$find[$key] = array('mode' => 'LIKE', 'value' => $value);
} elseif (substr(strtolower($key), -13) == '_greater_than') {
$key = substr($key, 0, -13);
$find[$key] = array('mode' => '>', 'value' => $value);
} elseif (substr(strtolower($key), -6) == '_after') {
$key = substr($key, 0, -6);
$find[$key] = array('mode' => '>', 'value' => $value);
} elseif (substr(strtolower($key), -10) == '_less_than') {
$key = substr($key, 0, -10);
$find[$key] = array('mode' => '<', 'value' => $value);
} elseif (substr(strtolower($key), -7) == '_before') {
$key = substr($key, 0, -7);
$find[$key] = array('mode' => '<', 'value' => $value);
} else {
$find[$key] = $value;
}
} else {
$find[$key] = $value;
}
}
} else {
throw new Exception('Number of fields and parameters don\'t match');
}
return $this->find($find, array('table' => $t, 'mode' => $mode, 'array' => $array));
} elseif (preg_match("/^find_or_(initialize|create)_by_([_a-zA-Z]\w*)$/", $f, $m)) {
$fields = explode("_and_", $m[2]);
$find = array();
if (count($fields) > 1 && is_array($a[0]) && count($fields) == count($a[0])) {
foreach ($fields as $i => $key) {
$value = $a[0][$i];
$find[$key] = $value;
}
} else {
$find[$m[2]] = $a[0];
}
$check = $this->find($find, array('mode' => 'AND'));
if (!empty($check)) {
return $check;
} else {
if ($m[1] == "create") {
$this->create($find);
return $this->find($this->lastId());
} elseif ($m[1] == "initialize") {
$row = $this->_new();
foreach ($find as $key => $value) {
$row->$key = $value;
}
return $row;
}
}
}
return false;
}
// _connect
// simple function, maybe enable use of other database engines?
private function _connect() {
if ($this->engine == 'mysql') {
return mysql_connect($this->host, $this->user, $this->pass);
}
}
// _query
// pretty simple again
private function _query($q) {
$this->q = $q; // store the last query
if ($this->engine == 'mysql') {
return mysql_query($q, $this->c);
}
}
// _num_rows
// pretty simple again
private function _num_rows($r) {
if ($this->engine == 'mysql') {
return mysql_num_rows($r);
}
}
// _select_db
// pretty simple again
private function _select_db() {
if ($this->engine == 'mysql') {
return mysql_select_db($this->db, $this->c);
}
}
// _close
// pretty simple again
private function _close() {
if ($this->engine == 'mysql') {
return mysql_close($this->c);
}
}
// _close
// pretty simple again
private function _auto_increment_id() {
if ($this->engine == 'mysql') {
return mysql_insert_id($this->c);
}
}
// _get
// accepts a query string, or mysql resource and returns either and array
// or an array of arrays depending on how many rows there are or if the
// $array variable is true
// private function _get($q, $array = false) {
private function _get($q, $options = array()) {
if (is_string($q)) {
$q = $this->_query($q);
}
if (!is_resource($q)) {
return false;
}
$r = $this->_num_rows($q);
$options['array'] = !empty($options['array']) ? $options['array'] : false;
$options['raw'] = isset($options['raw']) ? $options['raw'] : false;
if ($r) {
// if we have a result...
if ($r === 1 && !$options['array']) {
// if there is only 1 row and array is not forced
if ($this->engine == 'mysql') {
// if we're using mysql...
if ($options['raw']) {
// if $options row == true, return the raw array, not a DB record object
return mysql_fetch_assoc($q);
} else {
return new DB_record($this, mysql_fetch_assoc($q));
}
}
} else {
// $options array == true or we have more than one row
$a = array();
if ($this->engine == 'mysql') {
// if we're using mysql
while (($row = mysql_fetch_assoc($q)) != false) {
// create a $row variable with the contetnts of the row
if ($options['raw']) {
$a[] = $row;
} else {
$a[] = new DB_record($this, $row);
}
}
}
return $a;
}
} else {
return false;
}
}
public function query($q) {
return $this->_query($q);
}
// find
// builds a query to pass to get based on the variables passed
// if $id is null it will use the current data->id, if $id is an array it
// will match based on the array settings (correctly matching nulls), or
// $id can just be a specified id
// to match all users with a name like bob you could do:
// db->find(array('name' => array('mode' => 'LIKE', 'value' => '%bob%')), array('table' => 'users'));
// to retrieve all rows from the current table you could do:
// db->find();
// to retrieve a specific id you could do:
// db->find(123)
public function find($id = null, $options = array()) {
if (empty($options['table'])) {
if (!empty($this->table)) {
$options['table'] = $this->table;
} else {
return false;
}
}
if ($id === null) {
$options['array'] = isset($options['array']) ? $options['array'] : true; // default behaviour to return an array
$q = "SELECT * FROM `{$options['table']}`";
if (!empty($options['order']) && is_array($options['order'])) {
$q .= ' ORDER BY ';
$order = array();
foreach ($options['order'] as $field => $direction) {
$direction = strtoupper($direction);
if ($direction !== 'ASC' && $direction !== 'DESC') {
if ($field === 'RAND()') {
$order[] = 'RAND()';
} else {
$order[] .= "`{$field}`";
}
} else {
$order[] .= "`{$field}` {$direction}";
}
}
$q .= implode(", ", $order);
} elseif (!empty($options['order']) && is_string($options['order'])) {
$q .= " ORDER BY {$options['order']}";
}
if (empty($options['offset']) && !empty($options['limit'])) {
$q .= " LIMIT {$options['limit']}";
} elseif (!empty($options['offset']) && !empty($options['limit'])) {
$q .= " LIMIT {$options['offset']},{$options['limit']}";
}
$q .= ";";
return $this->_get($q, $options);
} else {
$options['array'] = isset($options['array']) ? $options['array'] : null;
$where = array();
if (is_array($id)) {
foreach ($id as $k => $v) {
if (is_array($v)) {
$where[] = "`{$k}` {$v['mode']} '{$v['value']}'";
} elseif ($v === null) {
$where[] = "ISNULL(`{$k}`)";
} else {
$where[] = "`{$k}` = '{$v}'";
}
}
} else {
$where[] = "`{$this->id}` = '{$id}'";
}
if (isset($options['mode']) || ($options['mode'] != "OR" && $options['mode'] != "AND")) {
$options['mode'] = 'OR';
}
$q = "SELECT * FROM `{$options['table']}` WHERE ".implode(" {$options['mode']} ", $where);
if (isset($options['order']) && !empty($options['order']) && is_array($optinos['order'])) {
$q .= ' ORDER BY ';
$order = array();
foreach ($options['order'] as $field => $direction) {
$direction = strtoupper($direction);
if ($direction !== 'ASC' || $direction !== 'DESC') {
if ($field === 'RAND()') {
$order[] = 'RAND()';
} else {
$order[] .= "`{$field}`";
}
} else {
$order[] .= "`{$field}` {$direction}";
}
}
$q .= implode(", ", $order);
} elseif (isset($options['order']) && !empty($options['order']) && is_string($options['order'])) {
$q .= " ORDER BY {$options['order']}";
}
if (empty($options['offset']) && !empty($options['limit'])) {
$q .= " LIMIT {$options['limit']}";
} elseif (!empty($options['offset']) && !empty($options['limit'])) {
$q .= " LIMIT {$options['offset']},{$options['limit']}";
}
$q .= ';';
return $this->_get($q, $options);
}
}
// create
// builds an INSERT query based on the variables passed
// $data must be an associative array with indexes matching the field names
// $table can be omitted and the current table will be used
// to insert a new row to the current table you could do:
// db->create(array("name" => "bob", "password" => md5(md5("mytest")), "email" => "bob@email.com"));
public function create($data = null, $options = array()) {
if (empty($options['table'])) {
if (!empty($this->table)) {
$options['table'] = $this->table;
} else {
return false;
}
}
if ($data !== null && is_array($data)) {
$set = array();
foreach ($data as $k => $v) {
if ($v === null) {
$set[] = "`{$k}` = NULL";
} else {
$set[] = "`{$k}` = '{$v}'";
}
}
$q = "INSERT INTO `{$options['table']}` SET ".implode(", ", $set).";";
$r = $this->_query($q);
if ($r) {
// if the query is successful return the create row
return $this->find($this->lastId());
} else {
// else return false
return false;
}
} else {
// data was null or not an array
return false;
}
}
// update
// builds an UPDATE query based on the variables passed
// $data must be an associative array with indexes matching the field names
// $table and $id can be omitted for the current id/table to be used
// to update the current record you could use:
// db->update(array("title" => "Cheese", "price" => 9.99));
public function update($data, $id = null, $options = array()) {
if (empty($options['table'])) {
if (!empty($this->table)) {
$options['table'] = $this->table;
} else {
return false;
}
}
if (is_array($data) && !empty($id)) {
$set = array();
foreach ($data as $k => $v) {
if ($v === null) {
$set[] = "`{$k}` = NULL";
} else {
$set[] = "`{$k}` = '{$v}'";
}
}
$q = "UPDATE `{$options['table']}` SET ".implode(", ", $set)." WHERE `{$this->id}` = '{$id}';";
return $this->_query($q);
} else {
return false;
}
}
// delete
// builds a DELETE query based on the variables passed
// all varibles are optional and will default to the current table/id
// $id can be an associative array of fields/values to match before deleting
// to delete all news posts by bob you could do:
// db->delete(array("user" => "bob"), "news");
// to delete all news posts by bob with car in the title you could do:
// db->delete(array("user" => "bob", "title" => array("mode" => "LIKE", "value" => "%car%")), "news", "OR");
public function delete($id = null, $options = array()) {
if (empty($options['table'])) {
if (!empty($this->table)) {
$options['table'] = $this->table;
} else {
return false;
}
}
$where = array();
if (is_array($id)) {
foreach ($id as $k => $v) {
if (is_array($v) && isset($v['mode'], $v['value'])) {
$where[] = "`{$k}` {$v['mode']} '{$v['value']}'";
} elseif ($v === null) {
$where[] = "ISNULL(`{$k}`)";
} elseif (!is_array($v) && !empty($v)) {
$where[] = "`{$k}` = '{$v}'";
}
}
} elseif (is_string($id) || is_numeric($id)) {
$where[] = "`{$this->id}` = {$id}";
}
if ($mode !== "AND" || $mode !== "OR") {
$mode = "AND";
}
$q = "DELETE FROM `{$options['table']}` WHERE ".implode(" {$mode} ", $where);
if (isset($options['limit']) && !empty($options['limit'])) {
$q .= " LIMIT {$options['limit']}";
}
$q .= ";";
return $this->_query($q);
}
// random
// returns $n, random rows from $table
public function random($n = 1, $options = array()) {
if (empty($options['table'])) {
if (!empty($this->table)) {
$options['table'] = $this->table;
} else {
return false;
}
}
if (!is_numeric($n)) {
$n = 1;
}
return $this->_get("SELECT * FROM `{$options['table']}` ORDER BY RAND() LIMIT {$n};");
}
// numRows
// returns the number of rows in $table
// $table can be omitted and the number of rows in the current table will be returned
public function numRows($options = array()) {
if (empty($options['table'])) {
if (!empty($this->table)) {
$options['table'] = $this->table;
} else {
return false;
}
}
$r = $this->_query("SELECT `{$this->id}` FROM `{$options['table']}`;");
return $this->_num_rows($r);
}
// lastId
// return the id of the last inserted row
public function lastId() {
return $this->_auto_increment_id();
}
// table
// creates a clone of the current db object using $options as the default table
// (or $options['table'] if $options is an array)
public function table($options = null) {
if ($options === null && !empty($this->table)) {
return clone $this;
} elseif (is_string($options) && !empty($options)) {
$r = clone $this;
$r->table = $options;
return $r;
} elseif (is_array($options) && isset($options['table']) && !empty($options['table'])) {
$r = clone $this;
$r->table = $options['table'];
return $r;
} else {
return false;
}
}
public function getFields($options = array()) {
if (!empty($this->fields)) {
return $this->fields;
} else {
if (empty($options['table'])) {
$options['table'] = $this->table;
} else {
return false;
}
$q = "SHOW FIELDS FROM `{$options['table']}`;";
$fields = $this->_get($q, array('raw' => true));
foreach ($fields as $field) {
if (isset($field['Field'])) {
$this->fields[] = $field['Field'];
} elseif (isset($field['field'])) {
$this->fields[] = $field['Field'];
} elseif (isset($field[0])) {
$this->fields[] = $field[0];
}
}
}
return $this->fields;
}
public function _new() {
return new DB_record($this);
}
}
class DB_record {
private $_data = array();
private $_db = null;
private $_new = false;
function __construct($db = null, $data = null) {
if (!empty($db)) {
$this->_db = $db;
}
if (is_array($data)) {
$this->_data = $data;
foreach ($this->_data as $key => $value) {
if (is_array($value)) {
$this->_data = null;
break;
} else {
$this->$key = $value;
}
}
} else {
$this->_new = true;
if (!empty($this->_db)) {
foreach ($this->_db->getFields() as $field) {
if ($field != $this->_db->id) {
$this->$field = null;
}
}
} else {
return false;
}
}
if (empty($this->_data) || empty($this->_db)) {
return false;
} else {
return $this;
}
}
function save() {
$save = array();
foreach ($this->_db->getFields() as $field) {
if (isset($this->$field) && $field != $this->_db->id) {
$this->_data[$field] = $this->$field;
$save[$field] = $this->$field;
}
}
$id = $this->_db->id;
if ($this->_new) {
$r = $this->_db->create($save);
$this->$id = $this->_db->lastId();
$this->_new = false;
return $r;
} else {
return $this->_db->update($save, $this->$id);
}
}
function isNew() {
return $this->_new;
}
}
?>以上是关于PHP PHP - 轻量级数据库和行集类，ActiveRecord样式函数的主要内容，如果未能解决你的问题，请参考以下文章