The SELECT statement is used to select data from a database.
选择语句[SELECT]是用来从一个数据库中选取数据的。

Select Data From a Database Table
从数据库表中选取数据

The SELECT statement is used to select data from a database.
选择语句[SELECT] 是用来从一个数据库中选取数据的。

Syntax
语法

SELECT column_name(s)
FROM table_name

Note: SQL statements are not case sensitive. SELECT is the same as select.
注意：SQL语句是“字母大小写不敏感”的语句（它不区分字母的大小写），即：“SELECT”和“select”是一样的。

To get PHP to execute the statement above we must use the mysql_query() function. This function is used to send a query or command to a MySQL connection.
在PHP内创建数据库，我们需要在mysql_query()函数内使用上述语句。这个函数是用来发送MySQL数据库连接建立的请求和指令的。

Example
案例

The following example selects all the data stored in the "Person" table (The * character selects all of the data in the table):
下面这个案例展示了如何从“Person”表中选择所有的数据（通配符“*”表示在表单中选择所有的数据）：

<?php
$con = mysql_connect("localhost","peter","abc123");
if (!$con) { die('Could not connect: ' . mysql_error()); }

mysql_select_db("my_db", $con);

$result = mysql_query("SELECT * FROM person");

while($row = mysql_fetch_array($result)) { echo $row['FirstName'] . " " . $row['LastName']; echo "<br />"; }

mysql_close($con);
?>

The example above stores the data returned by the mysql_query() function in the $result variable. Next, we use the mysql_fetch_array() function to return the first row from the recordset as an array. Each subsequent call to mysql_fetch_array() returns the next row in the recordset. The while loop loops through all the records in the recordset. To print the value of each row, we use the PHP $row variable ($row['FirstName'] and $row['LastName']).
上述案例储存了通过“$result”变量中的“mysql_query()”函数所返回的数据。接下来，我们使用“mysql_fetch_array()”函数将记录中的第一行记录以一个数组的形式返回；那么接下来，如果继续请求“mysql_fetch_array()”函数，那它将返回记录中的第二行，“while loop”语句循环显示了所有的记录。我们使用PHP “$row”变量($row['FirstName'] 和 $row['LastName'])来输出每一行得值。

The output of the code above will be:
上述代码的输出结果如下：

Peter Griffin
Glenn Quagmire

Display the Result in an HTML Table
在HTML表格中显示结果

The following example selects the same data as the example above, but will display the data in an HTML table:
下面这个案例：选择了与上述案例相同的数据，并在HTML表格中显示这些数据：

<?php
$con = mysql_connect("localhost","peter","abc123");
if (!$con) { die('Could not connect: ' . mysql_error()); }
mysql_select_db("my_db", $con);
$result = mysql_query("SELECT * FROM person");
echo "<table border='1'>
<tr>
<th>Firstname</th>
<th>Lastname</th>
</tr>";

while($row = mysql_fetch_array($result)) { echo "<tr>"; echo "<td>" . $row['FirstName'] . "</td>"; echo "<td>" . $row['LastName'] . "</td>"; echo "</tr>"; }
echo "</table>";

mysql_close($con);
?>

The output of the code above will be:
上述代码的输出结果如下：

MySQL 插入记录 MySQL Where

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