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<?php
class DB_text {
var $conn;
var $classname = "db_text";
var $database;
function on_create() {
}
function connect($database_name) {
$this->database = $database_name;
if(! file_exists($database_name)) {
$this->conn = array();
$this->_close();
}
$fp = fopen($this->database,"r");
$this->conn = unserialize(fread($fp,filesize($this->database)));
fclose($fp);
}
function &query;($query) {
if(eregi("select ",$query)) return $this->_select($query);
if(eregi("insert ",$query)) return $this->_insert($query);
if(eregi("delete ",$query)) return $this->_delete($query);
if(eregi("update ",$query)) return $this->_update($query);
return array();
}
function fetch_row(&$result) {
if(list($key,$value) = each($result))
return $value;
return false;
}
function num_rows($result) {
return count($result);
}

/**

• queryµÄ¸¨Öuº¯Êý
  /
  function _select($query) {
  if(eregi("(order by (.+))",$query,$regs)) {
  $order = $regs[2];
  $query = eregi_replace($regs[1],"",$query);
  }
  if(eregi("(group by (.+))",$query,$regs)) {
  $group = $regs[2];
  $query = eregi_replace($regs[1],"",$query);
  }
  eregi("select . from ([0-9a-z_]+) (where +(.+))?",$query,$regs);
  if($regs[3] != "") {
  $keys = $this->_where($regs[3],"\$this->conn[$regs[1]]");
  while(list($key,$value) = each($keys)) {
  $rs[] = $this->conn[$regs[1]][$value];
  }
  }else {
  $rs = $this->conn[$regs[1]];
  }
  if($order) {
  sscanf($order,"%s %s",$key,$type);
  if(empty($type)) $type = "asc";
  $this->_sort($rs,$key,$type);
  }
  return $rs;
  }
  function insert($query) {
  eregi("insert +into +([0-9a-z]+) (.+) values? (.+)",$query,$regs);
  eval("\$key=array$regs[2];");
  eval("\$value=array$regs[3];");
  for($i=0;$i<count($key);$i++)
  $rs[$key[$i]] = $value[$i];
  $this->conn[$regs[1]][] = $rs;
  $this->_close();
  }
  function update($query) {
  eregi("update +([0-9a-z]+) +set (,?.=.)+( +where +(.+))",$query,$regs);
  $regs[2] = eregi_replace(",","=",$regs[2]);
  $v = split("=",$regs[2]);
  $keys = $this->_where($regs[4],"\$this->conn[$regs[1]]");
  while(list($key,$value) = each($keys)) {
  for($i=0;$i<count($v);$i+=2)
  $this->conn[$regs[1]][$value][$v[$i]] = eregi_replace("'","",$v[$i+1]);
  }
  $this->_close();
  }
  function delete($query) {
  eregi("delete +from +([0-9a-z]+) (where +(.+))?",$query,$regs);
  $keys = $this->_where($regs[3],"\$this->conn[$regs[1]]");
  while(list($key,$value) = each($keys)) {
  unset($this->conn[$regs[1]][$value]);
  }
  reset($this->conn[$regs[1]]);
  while(list($key,$value) = each($this->conn[$regs[1]])) {
  $ch[] = $value;
  }
  $this->conn[$regs[1]] = $ch;
  $this->_close();
  }
  function _where($search,$table) {
  $search = eregi_replace("\("," ( ",$search);
  $search = eregi_replace("\)"," ) ",$search);
  $search = eregi_replace("\+"," + ",$search);
  $search = eregi_replace("\"," ",$search);
  while(eregi("^ ",$search,$regs)) {
  $search = eregi_replace($regs[1]," $regs[1] ",$search);
  }
  while(eregi("([><!] +=)",$search,$regs)) {
  $search = eregi_replace($regs[1],eregi_replace(" ","",$regs[1]),$search);
  }
  $search = eregi_replace(" "," ",trim($search));
  $search = eregi_replace(" and "," && ",$search);
  $search = eregi_replace(" or "," || ",$search);
  $search = eregi_replace(" = "," == ",$search);
  $ar = split(" ",$search);
  eval("\$t=$table;");

for($i=0;$i<count($ar);$i++) {  
  if(isset($t[0][$ar[$i]]))  
    $ar[$i] = "\$value[".$ar][$i]."]";  
}  
$expr = "\$expl=(".join(" ",$ar).");";  

while(list($key,$value) = each($t)) {  
  eval($expr);  
  if($expl)  
    $keys[] = $key;  
}  
return $keys;  

}
function _sort(&$ar,$key=0,$mode="desc") {
global $cmp_key;
$cmp_key = $key;
if($mode == "asc")
usort($ar,_cmp_asc);
else
usort($ar,_cmp_desc);
}
function _close() {
$fp = fopen($this->database,"w");
fwrite($fp,serialize($this->conn));
fclose($fp);
}
}

/* ÅÅÐo¼u
/
$cmp_key = "";

/* ÅÅÐoÓù¤×÷º¯Êý(½µÐo ÓÉusort()µ÷ÓÃ)
/
function _cmp_desc($a,$b) {
global $cmp_key;
if ($a[$cmp_key] == $b[$cmp_key]) return 0;
return ($a[$cmp_key] > $b[$cmp_key]) ? -1 : 1;
}

/* ÅÅÐoÓù¤×÷º¯Êý(ÉýÐo ÓÉusort()µ÷ÓÃ)
/
function _cmp_asc($a,$b) {
global $cmp_key;
if ($a[$cmp_key] == $b[$cmp_key]) return 0;
return ($a[$cmp_key] > $b[$cmp_key]) ? 1 : -1;
}
?>

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$conn = new DB_text;

$conn->connect("text1.txt");  

$conn->query("insert into manage (id,title) values (10,'abcd')");

$conn->query("insert into manage (id,title) values (2,'43d')");

$conn->query("insert into manage (id,title) values (20,'tuu')");

$conn->query("update manage set id=101,test='a' where id=10");

//$conn->query("delete from manage where id='10'");

//$conn->query("delete from manage where id=10 or table='code'");  
//$rt = $conn->query("select  from manage where id=101 or table='code' group by 1 order by 1 asc");

$rt = $conn->query("select  from manage group by 1 order by id desc");  
print_r($rt);  
?>