无意搜集到的一个mysql封装函数(php)

<span style="font-family: Arial, Helvetica, sans-serif;"><?php</span>

function dbConnect(){
global $db;
$db = DB_PCONNECT? mysql_pconnect(DB_HOST,DB_USERNAME,DB_PASSWORD): mysql_connect(DB_HOST,DB_USERNAME,DB_PASSWORD);
mysql_query("SET NAMES 'UTF8'");
mysql_select_db(DB_NAME,$db);
}
function dbClose(){
global $db;
mysql_close($db);
}
function dbExecute($sql){
global $db;
mysql_query($sql,$db);
return mysql_affected_rows($db);
}
function dbQuery($sql){
global $db;
$result = mysql_query($sql,$db);
while($row = mysql_fetch_assoc($result)){
$data[] = $row;
}
return $data;
}
function dbGetRow($sql){
global $db;
$result = mysql_query($sql,$db);
return mysql_num_rows($result)>0? mysql_fetch_assoc($result): null;
}
function dbGetField($sql, $field){
$result = dbGetRow($sql);
return count($result)==null? null: (isset($result[$field])? $result[$field]: null);
}
function makeInsertSql($table,$data){
$t1 = $t2 = array();
foreach($data as $key=>$value){
$t1[] = $key;
$t2[] = "'".$value."'";
}
//echo "insert into $table(".implode(',',$t1).") values(".implode(',',$t2).")";
return "insert into $table(".implode(',',$t1).") values(".implode(',',$t2).")";
}
function makeUpdateSql($table,$data,$condition){
$t1 = array();
foreach($data as $key=>$value){
$t1[] = "$key='".$value."'";
}
//echo "update $table set ".implode(',',$t1)." where $condition";
return "update $table set ".implode(',',$t1)." where $condition";
}
function startTrans(){
mysql_query("SET AUTOCOMMIT=0");
mysql_query("BEGIN");

}
function commit(){
mysql_query("COMMIT");
endTrans();
}
function rollback(){
mysql_query("ROLLBACK");
endTrans();
}
function endTrans(){
mysql_query("END");
mysql_query("SET AUTOCOMMIT=1");
}
function makeInsertAllSql($datas,$table){
if(!is_array($datas[0])) return false;
$fields = array_keys($datas[0]);
$values  =  array();
foreach ($datas as $data){
$value   =  array();
foreach ($data as $key=>$val){
$val   =  htmlspecialchars(addslashes($val));
if(is_scalar($val)) { // 过滤非标量数据
$value[]   =  is_string($val) ? "'{$val}'" : $val;
}
}
$values[]    = '('.implode(',', $value).')';
}
$sql =  ('INSERT').' INTO '.$table.' ('.implode(',', $fields).') VALUES '.implode(',',$values);

return $sql;
}
?>