下面是php将mysql数据库整库导出生成sql文件的详细代码，希望对大家在用php编程时备份数据有一定帮助

由网上搜到，有更改。    文件名：db_backup.php    源代码如下：   代码如下: <?php  ini_set("max_execution_time", "180");//避免数据量过大，导出不全的情况出现。    /*    程序功能：mysql数据库备份功能  作者：唐小刚  说明：  本程序主要是从mysqladmin中提取出来，并作出一定的调整，希望对大家在用php编程时备份数据有一定帮助.  如果不要备份结构：请屏掉这句:echo get_table_structure($dbname, $table, $crlf).";$crlf$crlf";  如果不要备份内容：请屏掉这句:echo get_table_content($dbname, $table, $crlf);    修改者：何锦盛  修改时间：2009/11/7  修改内容：新增函数get_table_structure，注释掉了函数get_table_def，目的是获得更丰富的建表时的细节（如：ENGINE=InnoDB AUTO_INCREMENT=80 DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci COMMENT='商品信息变更信息'）  */    $host="";//数据库地址    $dbname="";//这里配置数据库名    $username="";//用户名    $passw="";//这里配置密码    $filename=date("Y-m-d_H-i-s")."-".$dbname.".sql";  header("Content-disposition:filename=".$filename);//所保存的文件名  header("Content-type:application/octetstream");  header("Pragma:no-cache");  header("Expires:0");    //备份数据  $i = 0;  $crlf="rn";  global $dbconn;  $dbconn = mysql_connect($host,$username,$passw]);//数据库主机，用户名，密码  $db = mysql_select_db($dbname,$dbconn);  mysql_query("SET NAMES 'utf8'");  $tables =mysql_list_tables($dbname,$dbconn);  $num_tables = @mysql_numrows($tables);  print "-- filename=".$filename;  while($i < $num_tables)  {  $table=mysql_tablename($tables,$i);  print $crlf;  echo get_table_structure($dbname, $table, $crlf).";$crlf$crlf";  //echo get_table_def($dbname, $table, $crlf).";$crlf$crlf";  echo get_table_content($dbname, $table, $crlf);  $i++;  }    /*新增的获得详细表结构*/  function get_table_structure($db,$table,$crlf)  {  global $drop;    $schema_create = "";  if(!empty($drop)){ $schema_create .= "DROP TABLE IF EXISTS `$table`;$crlf";}  $result =mysql_db_query($db, "SHOW CREATE TABLE $table");  $row=mysql_fetch_array($result);  $schema_create .= $crlf."-- ".$row[0].$crlf;  $schema_create .= $row[1].$crlf;  Return $schema_create;  }    /*  //原来别人的取得数据库结构，但不完整  function get_table_def($db,$table,$crlf)  {  global $drop;    $schema_create = "";  if(!empty($drop))  $schema_create .= "DROP TABLE IF EXISTS `$table`;$crlf";    $schema_create .= "CREATE TABLE `$table` ($crlf";  $result = mysql_db_query($db, "SHOW full FIELDS FROM $table");  while($row = mysql_fetch_array($result))  {  $schema_create .= " `$row[Field]` $row[Type]";    if(isset($row["Default"]) && (!empty($row["Default"]) || $row["Default"] == "0"))  $schema_create .= " DEFAULT '$row[Default]'";  if($row["Null"] != "YES")  $schema_create .= " NOT NULL";  if($row["Extra"] != "")  $schema_create .= " $row[Extra]";  if($row["Comment"] != "")  $schema_create .= " Comment '$row[Comment]'";  $schema_create .= ",$crlf";  }  $schema_create = ereg_replace(",".$crlf."$", "", $schema_create);  $result = mysql_db_query($db, "SHOW KEYS FROM $table");  while($row = mysql_fetch_array($result))  {  $kname=$row['Key_name'];  if(($kname != "PRIMARY") && ($row['Non_unique'] == 0))  $kname="UNIQUE|$kname";  if(!isset($index[$kname]))  $index[$kname] = array();  $index[$kname][] = $row['Column_name'];  }    while(list($x,$columns) = @each($index))  {  $schema_create .= ",$crlf";  if($x == "PRIMARY")  $schema_create .= " PRIMARY KEY (".implode($columns,", ") . ")";  elseif (substr($x,0,6) == "UNIQUE")  $schema_create .= " UNIQUE ".substr($x,7)." (" . implode($columns, ", ") . ")";  else  $schema_create .= " KEY $x (" . implode($columns, ", ") . ")";  }    $schema_create .= "$crlf)";  return (stripslashes($schema_create));  }  */    //获得表内容  function get_table_content($db, $table, $crlf)  {  $schema_create = "";  $temp = "";  $result = mysql_db_query($db, "SELECT * FROM $table");  $i = 0;  while($row = mysql_fetch_row($result))  {  $schema_insert = "INSERT INTO `$table` VALUES (";  for($j=0; $j<mysql_num_fields($result);$j++)  {  if(!isset($row[$j]))  $schema_insert .= " NULL,";  elseif($row[$j] != "")  $schema_insert .= " '".addslashes($row[$j])."',";  else  $schema_insert .= " '',";  }  $schema_insert = ereg_replace(",$", "",$schema_insert);  $schema_insert .= ");$crlf";  $temp = $temp.$schema_insert ;  $i++;  }  return $temp;  }  ?>