与数据库连接

4.2 查询

假设与数据库已经连接就绪，下面我们就来实际的应用对数据库的查询。下面的代码演示了一个连接并查询的典型例子：
<?
/*

• 连接数据库并执行查询
  */
  function printoraerr($in_cur)
  {
  // 检查Oracle是否出错
  // 如果存在错误则显示
  // 当指针被激活时每次请求Oracle后调用该函数
  if(ora_errorcode($in_cur))
  echo "Oracle code - ".ora_error($in_cur)."\n";
  return;
  }
  /* 主程序 /
  if (!($conn=ora_logon("user@TNSNAME","password")))
  {
  echo "Connection to database failed\n";
  exit;
  }
  echo "Connected as connection - $conn
  \n";
  echo "Opening cursor ...
  \n";
  $cursor=ora_open($conn); printoraerr($cursor);
  echo "Opened cursor - $cursor
  \n";
  $qry="select user,sysdate from dual";
  echo "Parsing the query $qry ...
  \n";
  ora_parse($cursor,$qry,0); printoraerr($cursor);
  echo "Query parsed
  \n";
  echo "Executing cursor ...
  \n";
  ora_exec($cursor); printoraerr($cursor);
  echo "Executed cursor
  \n";
  echo "Fetching cursor ...
  \n";
  while(ora_fetch($cursor))
  {
  $user=ora_getcolumn($cursor,0); printoraerr($cursor);
  $sysdate=ora_getcolumn($cursor,1); printoraerr($cursor);
  echo " row = $user, $sysdate
  \n";
  }
  echo "Fetched all records
  \n";
  echo "Closing cursor ...
  \n";
  ora_close($cursor);
  echo "Closed cursor
  \n";
  echo "Logging off from oracle...
  \n";
  ora_logoff($conn);
  echo "Logged off from oracle
  \n";
  ?>
  （译者注：以上代码段缺少注释，请读者参考PHP Manual的Oracle数据库函数部分）

4.3 显示结果

以下代码演示了怎样查询数据库并将结果输出：
<?
function printoraerr($in_cur, $conn)
{
// 检查Oracle是否出错
// 如果存在错误则显示
// 当指针被激活时每次请求Oracle后调用该函数
// If it encountered an error, we exit immediately
if(ora_errorcode($in_cur))
{
echo "Oracle code - ".ora_error($in_cur)."
n";
ora_logoff($conn);
exit;
}
return;
}

function exequery($w_qry,$conn)
{
$cursor=ora_open($conn); printoraerr($cursor,$conn);
ora_parse($cursor,$w_qry,0); printoraerr($cursor,$conn);
ora_exec($cursor); printoraerr($cursor,$conn);
$numrows=0;
$w_numcols=ora_numcols($cursor);
// 显示头部
echo "
<TABLE WIDTH=\"100%\" BORDER=\"0\" CELLSPACING=\"1\" CELLPADDING=\"2\">

".  
ora_getcolumn($cursor,$i)."

// 主程序
if(!($conn=ora_logon("user@SID","password")))
{
echo "Error: Cannot connect to database\n";
exit;
}
$qry="SELECT
deptno \"Dept\"
,empno \"Emp\"
,empnm \"Name\"
,salary \"Salary\"
FROM
employee
ORDER BY 1,2";
exequery($qry);
ora_logoff($conn);
?>
（译者注：以上代码段缺少注释，请读者参考PHP Manual的Oracle数据库函数部分）

4.4 基于HTTP的Oracle登录

将以下代码加在PHP页面代码之前以确认Oracle登录。注意你必须正确设定$ SID。
<?
if(!isset($PHP_AUTH_USER))
{
Header("WWW-authenticate: basic realm=\"$SID\"");
Header("HTTP/1.0 401 Unauthorized");
$title="Login Instructions";
echo "

You are not authorized to enter the site

You are not authorised to enter the site