Php 检查查询结果是否为空行mysqli
我正在使用这段代码,但我不知道如何检查查询是否返回零行。我该怎么查呢Php 检查查询结果是否为空行mysqli,php,mysql,mysqli,Php,Mysql,Mysqli,我正在使用这段代码,但我不知道如何检查查询是否返回零行。我该怎么查呢 $results = $mysqli->query("SELECT ANNOUNCE_NUMBER,ANNOUNCEMENTS,ANNOUNCE_TYPE,POST_DATE FROM home WHERE ANNOUNCE_NUMBER NOT LIKE $excludewelcome AND ANNOUNCE_NUMBER NOT LIKE $excludenews ORDER BY ANNOUNCE_NUMBER
$results = $mysqli->query("SELECT ANNOUNCE_NUMBER,ANNOUNCEMENTS,ANNOUNCE_TYPE,POST_DATE FROM home WHERE ANNOUNCE_NUMBER NOT LIKE $excludewelcome AND ANNOUNCE_NUMBER NOT LIKE $excludenews ORDER BY ANNOUNCE_NUMBER DESC LIMIT $position, $items_per_group");
if ($results) {
//output results from database
while($obj = $results->fetch_object())
{
if($obj->ANNOUNCE_TYPE=='NEWSEVENTS')
{
$realstring='News and Events';
}
else
{
$realstring='Welcome Note';
}
echo '<li id="item_'.$obj->ANNOUNCE_NUMBER.'"><strong>'.$realstring.'</strong></span>';
echo '<br \>';
echo '('.$obj->POST_DATE.' ) <span class="page_message">'.$obj->ANNOUNCEMENTS.'</span></li>';
}
}
$results=$mysqli->query(“选择布告编号、布告、布告类型、布告日期,布告编号不象$excludewelcome,布告编号不象$excludenews,按布告编号描述限额$position,$items每组”);
如果($结果){
//从数据库输出结果
而($obj=$results->fetch_object())
{
如果($obj->annound_TYPE=='NEWSEVENTS')
{
$realstring='News and Events';
}
其他的
{
$realstring='Welcome Note';
}
echo“。$realstring.”;
回音“
”;
回显“(“$obj->POST_DATE.”)。$obj->公告。” ”;
}
}
您可以使用数据集上的来检查返回的行数。例如:
$results = $mysqli->query("SELECT ANNOUNCE_NUMBER,ANNOUNCEMENTS,ANNOUNCE_TYPE,POST_DATE FROM home WHERE ANNOUNCE_NUMBER NOT LIKE $excludewelcome AND ANNOUNCE_NUMBER NOT LIKE $excludenews ORDER BY ANNOUNCE_NUMBER DESC LIMIT $position, $items_per_group");
if ($results) {
if($results->num_rows === 0)
{
echo 'No results';
}
else
{
//output results from database
while($obj = $results->fetch_object())
{
if($obj->ANNOUNCE_TYPE=='NEWSEVENTS')
{
$realstring='News and Events';
}
else
{
$realstring='Welcome Note';
}
echo '<li id="item_'.$obj->ANNOUNCE_NUMBER.'"><strong>'.$realstring.'</strong></span>';
echo '<br \>';
echo '('.$obj->POST_DATE.' ) <span class="page_message">'.$obj->ANNOUNCEMENTS.'</span></li>';
}
}
}
$results=$mysqli->query(“选择布告编号、布告、布告类型、布告日期,布告编号不象$excludewelcome,布告编号不象$excludenews,按布告编号描述限额$position,$items每组”);
如果($结果){
如果($results->num_rows==0)
{
回应“没有结果”;
}
其他的
{
//从数据库输出结果
而($obj=$results->fetch_object())
{
如果($obj->annound_TYPE=='NEWSEVENTS')
{
$realstring='News and Events';
}
其他的
{
$realstring='Welcome Note';
}
echo“。$realstring.”;
回音“
”;
回显“(“$obj->POST_DATE.”)。$obj->公告。” ”;
}
}
}
如果数组为[null]或[null,null]或[null,null,null,…]
您可以使用内爆:
内爆用于将数组转换为字符串
$con = mysqli_connect("localhost","my_user","my_password","my_db");
$result = mysqli_query($con,'Select * From table1');
$row = mysqli_fetch_row($result);
if(implode(null,$row) == null){
//$row is empty
}else{
//$row has some value rather than null
}
但是我认为最好使用一个if:if($results)&($results->num_rows!==0)){1.当不需要粘合时,可以省略粘合参数。2.如果所有值都为null/空,则此检查将失败。