使用PHP來操作Oracle數(shù)據(jù)庫 11. 數(shù)據(jù)庫連接 在上一節(jié)里，我們已經(jīng)介紹了PHP與MySQL數(shù)據(jù)庫的一些基本操作知識，在互聯(lián)網(wǎng)中有關(guān)PHP與MySQL的教程也最多。MySQL是免費(fèi)的，這一點也許就吸引了不少人。由于其廣泛應(yīng)用，我就不想在這里贅述MySQL的使用方法了。Oracle被大量在企業(yè)應(yīng)用中采用，因此我們就利用Oracle來進(jìn)一步介紹PHP與數(shù)據(jù)庫的連接。我們當(dāng)然不會提及Oracle數(shù)據(jù)庫的設(shè)計原理，原因是這已經(jīng)超出了我們的討論范圍。 PHP提供了兩套函數(shù)與Oracle連接，分別是ORA_和OCI函數(shù)。其中ORA_函數(shù)略顯陳舊。OCI函數(shù)更新?lián)f更好一些。兩者的使用語法幾乎相差無幾。如前所述，你的PHP安裝選項應(yīng)該可以支持兩者的使用。 想獲得更多有關(guān)在Microsoft Windows平臺上安裝支持PHP3的Apache服務(wù)器的知識以及更多有關(guān)Oracle數(shù)據(jù)庫的知識，請查閱以下URL：www.csoft.net/~vsbabu/articles/oraphp.html。;;11.1 連接 <?;;if ($conn=Ora_Logon("user@TNSNAME","password"));;{ echo "<B>SUCCESS ! Connected to database<B>n"};;else;;{ echo "<B>Failed :-( Could not connect to database<B>n"} Ora_Logoff($conn); phpinfo(); ?> 以上代碼使用TNSNAME（在你的tnsnames.ora文件中指明）定義的Oracle數(shù)據(jù)庫名稱、用戶名稱和密碼連接數(shù)據(jù)庫。在成功連接的基礎(chǔ)上，ora_logon函數(shù)返回一個非零的連接ID并儲存在變量$conn中。 11.2 查詢 假設(shè)與數(shù)據(jù)庫已經(jīng)連接就緒，下面我們就來實際的應(yīng)用對數(shù)據(jù)庫的查詢。下面的代碼演示了一個連接并查詢的典型例子： <? /* * 連接數(shù)據(jù)庫并執(zhí)行查詢 */ function printoraerr($in_cur) { // 檢查Oracle是否出錯 // 如果存在錯誤則顯示 // 當(dāng)指針被激活時每次請求Oracle后調(diào)用該函數(shù) if(ora_errorcode($in_cur)) echo "Oracle code - ".ora_error($in_cur)."n"return; } /** 主程序 */ if (!($conn=ora_logon("user@TNSNAME","password")));;{ echo "Connection to database failedn"exit; } echo "Connected as connection - <b>$conn</b><br>n"echo "Opening cursor ...<br>n"$cursor=ora_open($conn); printoraerr($cursor); echo "Opened cursor - <b>$cursor</b><br>n"$qry="select user,sysdate from dual"echo "Parsing the query <b>$qry</b> ...<br>n"ora_parse($cursor,$qry,0); printoraerr($cursor); echo "Query parsed <br>n"echo "Executing cursor ...<br>n"ora_exec($cursor); printoraerr($cursor); echo "Executed cursor<br>n"echo "Fetching cursor ...<br>n"while(ora_fetch($cursor)) { $user=ora_getcolumn($cursor,0); printoraerr($cursor); $sysdate=ora_getcolumn($cursor,1); printoraerr($cursor); echo " row = <B>$user, $sysdate </B><br>n"} echo "Fetched all records<br>n"echo "Closing cursor ...<br>n"ora_close($cursor); echo "Closed cursor<br>n"echo "Logging off from oracle... <br>n"ora_logoff($conn); echo "Logged off from oracle <br>n"?> （譯者注：以上代碼段缺少注釋，請讀者參考PHP Manual的Oracle數(shù)據(jù)庫函數(shù)部分） 11.3 顯示結(jié)果 以下代碼演示了怎樣查詢數(shù)據(jù)庫并將結(jié)果輸出： <? function printoraerr($in_cur, $conn) { // 檢查Oracle是否出錯 // 如果存在錯誤則顯示 // 當(dāng)指針被激活時每次請求Oracle后調(diào)用該函數(shù) // If it encountered an error, we exit immediately if(ora_errorcode($in_cur));;{ echo "Oracle code - ".ora_error($in_cur)."<br>n"ora_logoff($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); // 顯示頭部 echo " <TABLE WIDTH="100%" BORDER="0" CELLSPACING="1" CELLPADDING="2"> <TR>n"for ($i=0;$i<$w_numcols;$i++) { $align=(ora_columntype($cursor,$i)=="NUMBER")?"RIGHT":"LEFT"echo "t<TH VALIGN=TOP ALIGN=$align>".ora_columnname($cursor,$i)."</TH>n"} echo "</TR>n"while(ora_fetch($cursor)) { echo "<TR>n"for ($i=0;$i<$w_numcols;$i++);;{ $align=(ora_columntype($cursor,$i)=="NUMBER")?"RIGHT":"LEFT"if(ora_columntype($cursor,$i)=="LONG") echo "<TD VALIGN=TOP ALIGN=$align><PRE>". ora_getcolumn($cursor,$i)."</PRE></TD>n"else echo "<TD VALIGN=TOP ALIGN=$align>".ora_getcolumn($cursor,$i)."</TD>n"printoraerr($cursor,$conn); } $numrows++; echo "</TR>n"} if ($numrows==0) echo "<TR><TD COLSPAN="$w_numcols"><B>Query returned no records </B></TD></TR>n"else;;{ echo "<TR>n"echo "<TH COLSPAN="".($w_numcols-1)."" ALIGN=RIGHT>Count</TH>n"echo "<TH ALIGN=RIGHT>$numrows</TH>n"echo "</TR>n"} echo "</TABLE>n"ora_close($cursor); return; } // 主程序 if(!($conn=ora_logon("user@SID","password")));;{ echo "Error: Cannot connect to databasen"exit; } $qry="SELECT deptno "Dept" ,empno "Emp" ,empnm "Name" ,salary "Salary" FROM employee ORDER BY 1,2"exequery($qry); ora_logoff($conn); ?> （譯者注：以上代碼段缺少注釋，請讀者參考PHP Manual的Oracle數(shù)據(jù)庫函數(shù)部分） 11.4 基于HTTP的Oracle登錄 將以下代碼加在PHP頁面代碼之前以確認(rèn)Oracle登錄。注意你必須正確設(shè)定$ SID。 <?;;if(!isset($PHP_AUTH_USER));;{ Header("WWW-authenticate: basic realm="$SID""); Header("HTTP/1.0 401 Unauthorized"); $title="Login Instructions"echo "<blockquote> You are not authorized to enter the site </blockquote> n"exit; };;else;;{ if (!($conn=ora_logon("$PHP_AUTH_USER@$SID",$PHP_AUTH_PW)));;{ Header("WWW-authenticate: basic realm="$SID""); Header("HTTP/1.0 401 Unauthorized"); $title="Login Instructions"echo "<blockquote> You are not authorised to enter the site </blockquote> n"exit; } } ?>;;;