計算機畢業設計外文翻譯----php訪問mysql-其他專業(編輯修改稿)

　

【文章內容簡介】 QL 語句作為參數。區別是要使用箭頭（ ）來通過對象調用函數，并且它返回的結果是另外一個對象而不是結果集。 $query = SELECT * FROM books $result = $connectionquery($query)。 這個代碼在連接對象上調用 query 函數，執行 SQL 查詢，返回結果對象 $result. 取結果 第 22 行在結果對象上調用方法 fetchRow。與 mysql_fetch_row 類似，這個方法一次返回一行數據： while ($result_row = $resultfetchRow( )) { echo 39。Title: 39。.$result_row[1] . 39。br /39。 13 echo 39。Author: 39。.$result_row[4] . 39。br / 39。 echo 39。Pages: 39。.$result_row[2] . 39。br /br /39。 } 使用一個 while 循環并調用 fetchRow 來遍歷所有行，直到 fetchRow 返回 FALSE。 循環內的代碼跟未使用 PEAR 的例子中的代碼一致。 關閉 第 30 行結束數據庫連接，它使用的是 DB 對象的 disconnect 方法： $connectiondisconnect( )。 PEAR錯誤報告 函數 DB：： isError 會檢查返回的結果是不是個錯誤。如果是，可以使用DB::errorMessae 得到錯誤對應的文字描述。你需要將函數的返回值傳遞給 DB：：errorMessage 作為參數。 下面使用 PEAR 代碼重寫錯誤檢查： ?php if ( DB::isError( $demoResult = $dbquery( $sql))) { echo DB::errorMessage($demoResult)。 } else { while ($demoRow = $demoResultfetchRow( )) { echo $demoRow[2] . 39。br /39。 } } ? PEAR 數據庫接口還提供了一個新版本叫做 PEAR：： MDB2。例 96給出了使用 MDB2版本重寫同一個例子的代碼。 例 98：使用 PEAR：： MDB2 顯示表 books ?php include(39。39。)。 require_once(39。39。)。 //Translate our database login information into an array. $dsn = array( 39。phptype39。 = 39。mysql39。, 14 39。username39。 = $username, 39。password39。 = $password, 39。hostspec39。 = $host, 39。database39。 = $database )。 //Create the connection as an MDB2 instance. $mdb2 = MDB2::factory($dsn)。 if (PEAR::isError($mdb2)) { die($mdb2getMessage( ))。 } //Set the fetchmode to field associative. $mdb2setFetchMode(MDB2_FETCHMODE_ASSOC)。 $query = SELECT * FROM books NATURAL JOIN authors。 $result =$mdb2query($query)。 if (PEAR::isError($result)){ die(Could not query the database:br /$query .$resultgetMessage( ))。 } //Display the results. echo(39。table border=139。)。 echo 39。trthTitle/ththAuthor/ththPages/th/tr39。 //Loop through the result set. while ($row = $resultfetchRow( )) { echo trtd。 echo htmlentities($row[39。title39。]) . 39。/tdtd39。 echo htmlentities($row[39。author 39。]) . 39。/tdtd39。 echo htmlentities($row[39。pages39。]) . 39。/td/tr39。 } echo(/table)。 //Close the connection. $resultfree( )。 ? 我們得到同樣的顯示結果。這個版本的 PEAR 數據庫抽象提供了更多的函數。 現在我們掌握了連接數據庫的方法以及 PEAR 提供的各種函數。 15 原文： Getting PHP to Talk to MySQl Now that you’re fortable using the MySQL client tools to manipulate data in the database, you can begin using PHP to display and modify data from the database. PHP has standard functions for working with the , we’re going to discuss PHP’s builtin database functions. We’ll also show you how to use the The PHP Extension and Application Repository (PEAR) database functions that provide the ability to use the same functions to access any supported database. This type of flexibility es from a process called abstraction. In programming interfaces, abstraction simplifies a plex interaction. It works by removing any nonessential parts of the interaction, allowing you to concentrate on the important parts. PEAR’s DB classes are one such database interface abstraction. The information you need to log into a database is reduced to the bare minimum. This standard format allows you to interact with MySQL, as well as other databases using the same functions. Similarly, other MySQLspecific functions are replaced with generic ones that know how to talk to many databases. For example, the MySQLspecific connect function is: mysql_connect($db_host, $db_username, $db_password)。 versus PEAR’s DB connect function: $connection = DB::connect( The same basic information is present in both mands, but the PEAR function also specifies the type of databases to which to connect. You can connect to MySQL or other supported databases. We’ll discuss both connection methods in detail. In this chapter, you’ll learn how to connect to a MySQL server fromPHP, how to use PHP to access and retrieve stored data, and how to correctly display information to the user. The Process The basic steps of performing a query, whether using the mysql mandline tool or PHP, are the same: ? Connect to the database. ? Select the database to use. ? Build a SELECT statement. ? Perform the query. ? Display the results. We’ll walk through each of these steps for both plain PHP and PEAR functions. Resources When connecting to a MySQL database, you will use two new resources. The first is the link identifier that holds all of the information necessary to connect to the database for an active connection. The other resource is the results resource. It contains all information required to retrieve results from an active database query’s result set. You’ll be creating and assigning both resources in this chapter. 16 Querying the Database with PHP Functions In this section, we introduce how to connect to a MySQL database with PHP. It’s quite simple, and we’ll begin shortly with examples, but we should talk briefly about what actually happens. When you try connecting to a MySQL database, the MySQL server authenticates you based on your username and password. PHP handles connecting to the database for you, and it allows you to start performing queries and gathering data immediately. As in Chapter 8, we’ll need the same pieces of information to connect to the database: ? The IP address of the database server ? The name of the database ? The username ? The password Before moving on, make sure you can log into your database using the MySQL mandline client. Figure 91 shows how the steps of the database interaction relate to the two types of resources. Building the SELECT statement happens before the third function call, but it is not shown. It’s done with plain PHP code, not a MySQLspecific PHP function. Figure 91. The interaction between functions and resources when using the database Including Database Login Details You’re going to create a file to hold the infor