php - 如何减少php连接mysql服务器的变量和连接数？

Question

我正在尝试减少此页面建立的连接数量。我读到的所有内容都表明，只有一个连接就足够了，但是如果我删除附加连接，该页面将不会连接到我的服务器并为我提供我正在寻找的结果。这也是我使用两次的查询之一，但如果我第二次调用原始查询，它也不起作用。

我做错了什么？

<?php
$dbaddress="localhost";
$dbuser="testuser";
$dbpass="testpass";
$dbname="testdb";
$dbtable="elo";
$query="SELECT Sequnce, mcacctname FROM  `elo`;";
$con=mysqli_connect($dbaddress,$dbuser,$dbpass,$dbname);
if (mysqli_connect_errno())
  {
  echo "Failed to connect to MySQL: " . mysqli_connect_error();
  }
mysql_connect($dbaddress, $dbuser, $dbpass);
mysql_select_db($dbname);
$sql = "SELECT Sequence, mcacctname FROM  `elo`;";
$result = mysql_query($sql);
mysql_connect($dbaddress, $dbuser, $dbpass);
mysql_select_db($dbname);
$sql2 = "SELECT Sequence, mcacctname FROM  `elo`;";
$result2 = mysql_query($sql2);
$sqlstart = "SELECT mcacctname, elo  FROM  `elo`;";
$q = mysql_query($sqlstart);
?>
<form name="player1" method="post" action="predictions.php">
<label for="Select Player 1">Select Player 1:
<?php
echo "<select name='elouser1'>";
while ($row = mysql_fetch_array($result)) {
echo "<option value='" . $row['Sequence'] . "'>" . $row['mcacctname'] . "</option>";
}
echo "</select>";
?>
</label>
<input type="submit" value="Player 1 Wins">
</form>
<br>
<form name="player2" method="post" action="predictions.php">
<label for="Select Player 2">Select Player 2:
<?php
echo "<select name='elouser2'>";
while ($row2 = mysql_fetch_array($result2)) {
    echo "<option value='" . $row2['Sequence'] . "'>" . $row2['mcacctname'] . "</option>";
}
echo "</select>";
?>
</label>
<input type="submit" value="Player 2 Wins">
</form>
<table>
<tr>
<?
echo '<div class="container">';
while($res = mysql_fetch_array($q)){
echo '<tr><td><div class="item">'.  $res['mcacctname'] . '</td><td>' . $res    ['elo'] . '</div></td></tr>';
}
echo '</div>';
mysqli_close($con);
?>
</tr>
</table>

Answer 1

在页面中打开连接后，您无需为每个查询重新打开它。您可以简单地删除所有创建连接并选择数据库的语句(第一个语句除外)。

注意您使用mysqli打开连接，但使用mysql查询它。两组函数不可互换:使用mysqli，因为“mysql”已弃用，并且将来将删除支持。

试试这个:

$dbaddress="localhost";
$dbuser="testuser";
$dbpass="testpass";
$dbname="testdb";
$dbtable="elo";
$query="SELECT Sequence, mcacctname FROM  `elo`;";
$con=mysqli_connect($dbaddress,$dbuser,$dbpass,$dbname);
if (mysqli_connect_errno())
  {
  echo "Failed to connect to MySQL: " . mysqli_connect_error();
  }
$sql = "SELECT Sequence, mcacctname FROM  `elo`;";
$result = mysqli_query($con,$sql) or die(mysqli_error($con));
$sql2 = "SELECT Sequence, mcacctname FROM  `elo`;";
$result2 = mysqli_query($con,$sql2) or die(mysqli_error($con));
$sqlstart = "SELECT mcacctname, elo  FROM  `elo`;";
$q = mysqli_query($con, $sqlstart) or die(mysqli_error($con));
?>
<form name="player1" method="post" action="predictions.php">
<label for="Select Player 1">Select Player 1:
<?php
echo "<select name='elouser1'>";
while ($row = mysqli_fetch_array($result)) {
echo "<option value='" . $row['Sequence'] . "'>" . $row['mcacctname'] . "</option>";
}
echo "</select>";
?>
</label>
<input type="submit" value="Player 1 Wins">
</form>
<br>
<form name="player2" method="post" action="predictions.php">
<label for="Select Player 2">Select Player 2:
<?php
echo "<select name='elouser2'>";
while ($row2 = mysqli_fetch_array($result2)) {
    echo "<option value='" . $row2['Sequence'] . "'>" . $row2['mcacctname'] . "</option>";
}
echo "</select>";
?>
</label>
<input type="submit" value="Player 2 Wins">
</form>
<table>
<tr>
<?
echo '<div class="container">';
while($res = mysqli_fetch_array($q)){
echo '<tr><td><div class="item">'.  $res['mcacctname'] . '</td><td>' . $res    ['elo'] . '</div></td></tr>';
}
echo '</div>';
mysqli_close($con);
?>
</tr>
</table>