PHP 好用的数据库操作类

开始学习PHP之后。一直再使用的PHP mysql数据库操作类。

1.sql_core.php

<?php
	/**********************************************************************
	*  ezSQL Constants
	*/

	define("EZSQL_VERSION","2.03");
	define("OBJECT","OBJECT",true);
	define("ARRAY_A","ARRAY_A",true);
	define("ARRAY_N","ARRAY_N",true);
	define("EZSQL_CORE_ERROR","ezSQLcore can not be used by itself (it is designed for use by database specific modules).");


	/**********************************************************************
	*  Core class containg common functions to manipulate query result
	*  sets once returned
	*/

	class ezSQLcore
	{

		var $trace            = false;  // same as $debug_all
		var $debug_all        = false;  // same as $trace
		var $debug_called     = false;
		var $vardump_called   = false;
		var $show_errors      = true;
		var $num_queries      = 0;
		var $last_query       = null;
		var $last_error       = null;
		var $col_info         = null;
		var $captured_errors  = array();
		var $cache_dir        = false;
		var $cache_queries    = false;
		var $cache_inserts    = false;
		var $use_disk_cache   = false;
		var $cache_timeout    = 24; // hours

		// == TJH == default now needed for echo of debug function
		var $debug_echo_is_on = true;

		/**********************************************************************
		*  Constructor
		*/

		function ezSQLcore()
		{
		}

		/**********************************************************************
		*  Connect to DB - over-ridden by specific DB class
		*/

		function connect()
		{
			die(EZSQL_CORE_ERROR);
		}

		/**********************************************************************
		*  Select DB - over-ridden by specific DB class
		*/

		function select()
		{
			die(EZSQL_CORE_ERROR);
		}

		/**********************************************************************
		*  Basic Query	- over-ridden by specific DB class
		*/

		function query()
		{
			die(EZSQL_CORE_ERROR);
		}

		/**********************************************************************
		*  Format a string correctly for safe insert - over-ridden by specific
		*  DB class
		*/

		function escape()
		{
			die(EZSQL_CORE_ERROR);
		}

		/**********************************************************************
		*  Return database specific system date syntax
		*  i.e. Oracle: SYSDATE Mysql: NOW()
		*/

		function sysdate()
		{
			die(EZSQL_CORE_ERROR);
		}

		/**********************************************************************
		*  Print SQL/DB error - over-ridden by specific DB class
		*/

		function register_error($err_str)
		{
			// Keep track of last error
			$this->last_error = $err_str;

			// Capture all errors to an error array no matter what happens
			$this->captured_errors[] = array
			(
				"error_str" => $err_str,
				"query"     => $this->last_query
			);
		}

		/**********************************************************************
		*  Turn error handling on or off..
		*/

		function show_errors()
		{
			$this->show_errors = true;
		}

		function hide_errors()
		{
			$this->show_errors = false;
		}

		/**********************************************************************
		*  Kill cached query results
		*/

		function flush()
		{
			// Get rid of these
			$this->last_result = null;
			$this->col_info = null;
			$this->last_query = null;
			$this->from_disk_cache = false;
		}

		/**********************************************************************
		*  Get one variable from the DB - see docs for more detail
		*/

		function get_var($query=null,$x=0,$y=0)
		{

			// Log how the function was called
			$this->func_call = "$db->get_var("$query",$x,$y)";

			// If there is a query then perform it if not then use cached results..
			if ( $query )
			{
				$this->query($query);
			}

			// Extract var out of cached results based x,y vals
			if ( $this->last_result[$y] )
			{
				$values = array_values(get_object_vars($this->last_result[$y]));
			}

			// If there is a value return it else return null
			return (isset($values[$x]) && $values[$x]!=="")?$values[$x]:null;
		}

		/**********************************************************************
		*  Get one row from the DB - see docs for more detail
		*/

		function get_row($query=null,$output=OBJECT,$y=0)
		{

			// Log how the function was called
			$this->func_call = "$db->get_row("$query",$output,$y)";

			// If there is a query then perform it if not then use cached results..
			if ( $query )
			{
				$this->query($query);
			}

			// If the output is an object then return object using the row offset..
			if ( $output == OBJECT )
			{
				return $this->last_result[$y]?$this->last_result[$y]:null;
			}
			// If the output is an associative array then return row as such..
			elseif ( $output == ARRAY_A )
			{
				return $this->last_result[$y]?get_object_vars($this->last_result[$y]):null;
			}
			// If the output is an numerical array then return row as such..
			elseif ( $output == ARRAY_N )
			{
				return $this->last_result[$y]?array_values(get_object_vars($this->last_result[$y])):null;
			}
			// If invalid output type was specified..
			else
			{
				$this->print_error(" $db->get_row(string query, output type, int offset) -- Output type must be one of: OBJECT, ARRAY_A, ARRAY_N");
			}

		}

		/**********************************************************************
		*  Function to get 1 column from the cached result set based in X index
		*  see docs for usage and info
		*/

		function get_col($query=null,$x=0)
		{

			// If there is a query then perform it if not then use cached results..
			if ( $query )
			{
				$this->query($query);
			}

			// Extract the column values
			for ( $i=0; $i < count($this->last_result); $i++ )
			{
				$new_array[$i] = $this->get_var(null,$x,$i);
			}

			return $new_array;
		}


		/**********************************************************************
		*  Return the the query as a result set - see docs for more details
		*/

		function get_results($query=null, $output = OBJECT)
		{

			// Log how the function was called
			$this->func_call = "$db->get_results("$query", $output)";

			// If there is a query then perform it if not then use cached results..
			if ( $query )
			{
				$this->query($query);
			}

			// Send back array of objects. Each row is an object
			if ( $output == OBJECT )
			{
				return $this->last_result;
			}
			elseif ( $output == ARRAY_A || $output == ARRAY_N )
			{
				if ( $this->last_result )
				{
					$i=0;
					foreach( $this->last_result as $row )
					{

						$new_array[$i] = get_object_vars($row);

						if ( $output == ARRAY_N )
						{
							$new_array[$i] = array_values($new_array[$i]);
						}

						$i++;
					}

					return $new_array;
				}
				else
				{
					return null;
				}
			}
		}


		/**********************************************************************
		*  Function to get column meta data info pertaining to the last query
		* see docs for more info and usage
		*/

		function get_col_info($info_type="name",$col_offset=-1)
		{

			if ( $this->col_info )
			{
				if ( $col_offset == -1 )
				{
					$i=0;
					foreach($this->col_info as $col )
					{
						$new_array[$i] = $col->{$info_type};
						$i++;
					}
					return $new_array;
				}
				else
				{
					return $this->col_info[$col_offset]->{$info_type};
				}

			}

		}

		/**********************************************************************
		*  store_cache
		*/

		function store_cache($query,$is_insert)
		{

			// The would be cache file for this query
			$cache_file = $this->cache_dir."/".md5($query);

			// disk caching of queries
			if ( $this->use_disk_cache && ( $this->cache_queries && ! $is_insert ) || ( $this->cache_inserts && $is_insert ))
			{
				if ( ! is_dir($this->cache_dir) )
				{
					$this->register_error("Could not open cache dir: $this->cache_dir");
					$this->show_errors ? trigger_error("Could not open cache dir: $this->cache_dir",E_USER_WARNING) : null;
				}
				else
				{
					// Cache all result values
					$result_cache = array
					(
						"col_info" => $this->col_info,
						"last_result" => $this->last_result,
						"num_rows" => $this->num_rows,
						"return_value" => $this->num_rows,
					);
					error_log ( serialize($result_cache), 3, $cache_file);
				}
			}

		}

		/**********************************************************************
		*  get_cache
		*/

		function get_cache($query)
		{

			// The would be cache file for this query
			$cache_file = $this->cache_dir."/".md5($query);

			// Try to get previously cached version
			if ( $this->use_disk_cache && file_exists($cache_file) )
			{
				// Only use this cache file if less than "cache_timeout" (hours)
				if ( (time() - filemtime($cache_file)) > ($this->cache_timeout*3600) )
				{
					unlink($cache_file);
				}
				else
				{
					$result_cache = unserialize(file_get_contents($cache_file));

					$this->col_info = $result_cache["col_info"];
					$this->last_result = $result_cache["last_result"];
					$this->num_rows = $result_cache["num_rows"];

					$this->from_disk_cache = true;

					// If debug ALL queries
					$this->trace || $this->debug_all ? $this->debug() : null ;

					return $result_cache["return_value"];
				}
			}

		}

		/**********************************************************************
		*  Dumps the contents of any input variable to screen in a nicely
		*  formatted and easy to understand way - any type: Object, Var or Array
		*/

		function vardump($mixed="")
		{

			// Start outup buffering
			ob_start();

			echo "<p><table><tr><td bgcolor=ffffff><blockquote><font color=000090>";
			echo "<pre><font face=arial>";

			if ( ! $this->vardump_called )
			{
				echo "<font color=800080><b>ezSQL</b> (v".EZSQL_VERSION.") <b>Variable Dump..</b></font>

";
			}

			$var_type = gettype ($mixed);
			print_r(($mixed?$mixed:"<font color=red>No Value / False</font>"));
			echo "

<b>Type:</b> " . ucfirst($var_type) . "
";
			echo "<b>Last Query</b> [$this->num_queries]<b>:</b> ".($this->last_query?$this->last_query:"NULL")."
";
			echo "<b>Last Function Call:</b> " . ($this->func_call?$this->func_call:"None")."
";
			echo "<b>Last Rows Returned:</b> ".count($this->last_result)."
";
			echo "</font></pre></font></blockquote></td></tr></table>".$this->donation();
			echo "
<hr size=1 noshade color=dddddd>";

			// Stop output buffering and capture debug HTML
			$html = ob_get_contents();
			ob_end_clean();

			// Only echo output if it is turned on
			if ( $this->debug_echo_is_on )
			{
				echo $html;
			}

			$this->vardump_called = true;

			return $html;

		}

		/**********************************************************************
		*  Alias for the above function
		*/

		function dumpvar($mixed)
		{
			$this->vardump($mixed);
		}

		/**********************************************************************
		*  Displays the last query string that was sent to the database & a
		* table listing results (if there were any).
		* (abstracted into a seperate file to save server overhead).
		*/

		function debug()
		{

			// Start outup buffering
			ob_start();

			echo "<blockquote>";

			// Only show ezSQL credits once..
			if ( ! $this->debug_called )
			{
				echo "<font color=800080 face=arial size=2><b>ezSQL</b> (v".EZSQL_VERSION.") <b>Debug..</b></font><p>
";
			}

			if ( $this->last_error )
			{
				echo "<font face=arial size=2 color=000099><b>Last Error --</b> [<font color=000000><b>$this->last_error</b></font>]<p>";
			}

			if ( $this->from_disk_cache )
			{
				echo "<font face=arial size=2 color=000099><b>Results retrieved from disk cache</b></font><p>";
			}

			echo "<font face=arial size=2 color=000099><b>Query</b> [$this->num_queries] <b>--</b> ";
			echo "[<font color=000000><b>$this->last_query</b></font>]</font><p>";

				echo "<font face=arial size=2 color=000099><b>Query Result..</b></font>";
				echo "<blockquote>";

			if ( $this->col_info )
			{

				// =====================================================
				// Results top rows

				echo "<table cellpadding=5 cellspacing=1 bgcolor=555555>";
				echo "<tr bgcolor=eeeeee><td nowrap valign=bottom><font color=555599 face=arial size=2><b>(row)</b></font></td>";


				for ( $i=0; $i < count($this->col_info); $i++ )
				{
					echo "<td nowrap align=left valign=top><font size=1 color=555599 face=arial>{$this->col_info[$i]->type} {$this->col_info[$i]->max_length}</font><br><span style="font-family: arial; font-size: 10pt; font-weight: bold;">{$this->col_info[$i]->name}</span></td>";
				}

				echo "</tr>";

				// ======================================================
				// print main results

			if ( $this->last_result )
			{

				$i=0;
				foreach ( $this->get_results(null,ARRAY_N) as $one_row )
				{
					$i++;
					echo "<tr bgcolor=ffffff><td bgcolor=eeeeee nowrap align=middle><font size=2 color=555599 face=arial>$i</font></td>";

					foreach ( $one_row as $item )
					{
						echo "<td nowrap><font face=arial size=2>$item</font></td>";
					}

					echo "</tr>";
				}

			} // if last result
			else
			{
				echo "<tr bgcolor=ffffff><td colspan=".(count($this->col_info)+1)."><font face=arial size=2>No Results</font></td></tr>";
			}

			echo "</table>";

			} // if col_info
			else
			{
				echo "<font face=arial size=2>No Results</font>";
			}

			echo "</blockquote></blockquote>".$this->donation()."<hr noshade color=dddddd size=1>";

			// Stop output buffering and capture debug HTML
			$html = ob_get_contents();
			ob_end_clean();

			// Only echo output if it is turned on
			if ( $this->debug_echo_is_on )
			{
				echo $html;
			}

			$this->debug_called = true;

			return $html;

		}

		/**********************************************************************
		*  Naughty little function to ask for some remuniration!
		*/

		function donation()
		{
			return "<font size=1 face=arial color=000000>If ezSQL has helped <a href="https://www.paypal.com/xclick/business=justin%40justinvincent.com&item_name=ezSQL&no_note=1&tax=0" style="color: 0000CC;">make a donation!?</a>   <!--[ go on! you know you want to! ]--></font>";
		}

	}

?>

2.sql.php

<?php

	/**********************************************************************
	*  ezSQL error strings - mySQL
	*/

	$ezsql_mysql_str = array
	(
		1 => "Require $dbuser and $dbpassword to connect to a database server",
		2 => "Error establishing mySQL database connection. Correct user/password? Correct hostname? Database server running?",
		3 => "Require $dbname to select a database",
		4 => "mySQL database connection is not active",
		5 => "Unexpected error while trying to select database"
	);

	/**********************************************************************
	*  ezSQL Database specific class - mySQL
	*/

	if ( ! function_exists ("mysql_connect") ) die("<b>Fatal Error:</b> ezSQL_mysql requires mySQL Lib to be compiled and or linked in to the PHP engine");
	if ( ! class_exists ("ezSQLcore") ) die("<b>Fatal Error:</b> ezSQL_mysql requires ezSQLcore (ez_sql_core.php) to be included/loaded before it can be used");

	class ezSQL_mysql extends ezSQLcore
	{

		var $dbuser = false;
		var $dbpassword = false;
		var $dbname = false;
		var $dbhost = false;

		/**********************************************************************
		*  Constructor - allow the user to perform a qucik connect at the
		*  same time as initialising the ezSQL_mysql class
		*/

		function ezSQL_mysql($dbuser="", $dbpassword="", $dbname="", $dbhost="localhost")
		{
			$this->dbuser = $dbuser;
			$this->dbpassword = $dbpassword;
			$this->dbname = $dbname;
			$this->dbhost = $dbhost;
		}

		/**********************************************************************
		*  Short hand way to connect to mySQL database server
		*  and select a mySQL database at the same time
		*/

		function quick_connect($dbuser="", $dbpassword="", $dbname="", $dbhost="localhost")
		{
			$return_val = false;
			if ( ! $this->connect($dbuser, $dbpassword, $dbhost,true) ) ;
			else if ( ! $this->select($dbname) ) ;
			else $return_val = true;
			return $return_val;
		}

		/**********************************************************************
		*  Try to connect to mySQL database server
		*/

		function connect($dbuser="", $dbpassword="", $dbhost="localhost")
		{
			global $ezsql_mysql_str; $return_val = false;

			// Must have a user and a password
			if ( ! $dbuser )
			{
				$this->register_error($ezsql_mysql_str[1]." in ".__FILE__." on line ".__LINE__);
				$this->show_errors ? trigger_error($ezsql_mysql_str[1],E_USER_WARNING) : null;
			}
			// Try to establish the server database handle
			else if ( ! $this->dbh = @mysql_connect($dbhost,$dbuser,$dbpassword,true) )
			{
				$this->register_error($ezsql_mysql_str[2]." in ".__FILE__." on line ".__LINE__);
				$this->show_errors ? trigger_error($ezsql_mysql_str[2],E_USER_WARNING) : null;
			}
			else
			{
				$this->dbuser = $dbuser;
				$this->dbpassword = $dbpassword;
				$this->dbhost = $dbhost;
				$return_val = true;
			}

			return $return_val;
		}

		/**********************************************************************
		*  Try to select a mySQL database
		*/

		function select($dbname="")
		{
			global $ezsql_mysql_str; $return_val = false;

			// Must have a database name
			if ( ! $dbname )
			{
				$this->register_error($ezsql_mysql_str[3]." in ".__FILE__." on line ".__LINE__);
				$this->show_errors ? trigger_error($ezsql_mysql_str[3],E_USER_WARNING) : null;
			}

			// Must have an active database connection
			else if ( ! $this->dbh )
			{
				$this->register_error($ezsql_mysql_str[4]." in ".__FILE__." on line ".__LINE__);
				$this->show_errors ? trigger_error($ezsql_mysql_str[4],E_USER_WARNING) : null;
			}

			// Try to connect to the database
			else if ( !@mysql_select_db($dbname,$this->dbh) )
			{
				// Try to get error supplied by mysql if not use our own
				if ( !$str = @mysql_error($this->dbh))
					  $str = $ezsql_mysql_str[5];

				$this->register_error($str." in ".__FILE__." on line ".__LINE__);
				$this->show_errors ? trigger_error($str,E_USER_WARNING) : null;
			}
			else
			{
				$this->dbname = $dbname;
				$return_val = true;
			}

			return $return_val;
		}

		/**********************************************************************
		*  Format a mySQL string correctly for safe mySQL insert
		*  (no mater if magic quotes are on or not)
		*/

		function escape($str)
		{
			return mysql_escape_string(stripslashes($str));
		}

		/**********************************************************************
		*  Return mySQL specific system date syntax
		*  i.e. Oracle: SYSDATE Mysql: NOW()
		*/

		function sysdate()
		{
			return "NOW()";
		}

		/**********************************************************************
		*  Perform mySQL query and try to detirmin result value
		*/

		function query($query)
		{

			// Initialise return
			$return_val = 0;

			// Flush cached values..
			$this->flush();

			// For reg expressions
			$query = trim($query);

			// Log how the function was called
			$this->func_call = "$db->query("$query")";

			// Keep track of the last query for debug..
			$this->last_query = $query;

			// Count how many queries there have been
			$this->num_queries++;

			// Use core file cache function
			if ( $cache = $this->get_cache($query) )
			{
				return $cache;
			}

			// If there is no existing database connection then try to connect
			if ( ! isset($this->dbh) || ! $this->dbh )
			{
				$this->connect($this->dbuser, $this->dbpassword, $this->dbhost);
				$this->select($this->dbname);
			}

			// Perform the query via std mysql_query function..
			$this->result = @mysql_query($query,$this->dbh);

			// If there is an error then take note of it..
			if ( $str = @mysql_error($this->dbh) )
			{
				$is_insert = true;
				$this->register_error($str);
				$this->show_errors ? trigger_error($str,E_USER_WARNING) : null;
				return false;
			}

			// Query was an insert, delete, update, replace
			$is_insert = false;
			if ( preg_match("/^(insert|delete|update|replace)s+/i",$query) )
			{
				$this->rows_affected = @mysql_affected_rows();

				// Take note of the insert_id
				if ( preg_match("/^(insert|replace)s+/i",$query) )
				{
					$this->insert_id = @mysql_insert_id($this->dbh);
				}

				// Return number fo rows affected
				$return_val = $this->rows_affected;
			}
			// Query was a select
			else
			{

				// Take note of column info
				$i=0;
				while ($i < @mysql_num_fields($this->result))
				{
					$this->col_info[$i] = @mysql_fetch_field($this->result);
					$i++;
				}

				// Store Query Results
				$num_rows=0;
				while ( $row = @mysql_fetch_object($this->result) )
				{
					// Store relults as an objects within main array
					$this->last_result[$num_rows] = $row;
					$num_rows++;
				}

				@mysql_free_result($this->result);

				// Log number of rows the query returned
				$this->num_rows = $num_rows;

				// Return number of rows selected
				$return_val = $this->num_rows;
			}

			// disk caching of queries
			$this->store_cache($query,$is_insert);

			// If debug ALL queries
			$this->trace || $this->debug_all ? $this->debug() : null ;

			return $return_val;

		}

	}

?>

3.sql_config.php

<?php

include_once "sql_core.php";

include_once "sql.php";

$db = new ezSQL_mysql("数据库用户", "密码", "数据库名字", "数据库服务器地址，默认localhost，带端口号");

$db->query("SET NAMES UTF8");

?>

4.直接在需要链接数据库的地方 使用 

include_once ("sql_config.php");

就可以使用$db变量。

方法列表如下：

$db->query($sql);  //$sql语句中，update 或者 delete 语句，返回值是$sql语句影响的行数。

$db->get_row($sql); //$sql是获取 一条 数据的SQL

$db->get_results($sql); //$sql是可以获取多条数据的SQL

$db->get_var($sql); //$sql是获得某一个字段的值的SQL
 

完整代码：http://download.csdn.net/detail/jsj2009145520/8588979