如何仅在PHP中获取第一行的特定列数据SQL? [英] How to get specific column data SQL for first row only in PHP?

问题描述

我正在使用 PHP 来回显 SQL 数据库中的一些记录.这看起来很容易，但我无法理解.所以基本上，我只想获取第一行的所有列 a,b,c,d,e，其余行只获取 a,b,c.

I'm using PHP to echo out some records in SQL database. This seems easy but I can't get it. So basically, I want to get all the columns a,b,c,d,e for the first row only and just a,b,c for the rest of the rows.

$query = $assdb->prepare("Select a, b, c, d, e from Table");
$query->execute();
$stmt = $query->fetchAll(PDO::FETCH_ASSOC);

foreach($stmt as $row){
echo $row['a'] . $row['b']  . $row['c'];

//IF FIRST ROW, THEN ECHO $row['d'] and $row['e'], BUT IT DOES NOT WORK
if($row == 1){
    echo $row['d'] and $row['e']; 
  }

}//END FOREACH LOOP

我如何检查第一行?然后向其中添加特定数据?

HOW DO I CHECK FOR FIRST ROW? AND THEN ADD SPECIFIC DATA TO IT?

推荐答案

Use simple flag $is_first:

Use simple flag $is_first:

$is_first = true;
foreach ($stmt as $row){
    echo $row['a'] . $row['b']  . $row['c'];

    //IF FIRST ROW, THEN ECHO $row['d'] and $row['e']
    if ($is_first) {
       echo $row['d'] . $row['e']; 
       $is_first = false;
    }
} //END FOREACH LOOP

否则你可以使用 foreach 之类的

Else you can use foreach like

foreach ($stmt as $key => $row) {
    echo $row['a'] . $row['b']  . $row['c'];
    if ($key == 0) {
        echo $row['d'] . $row['e']; 
    }
}

如果您 $stmt 是零索引数组，请检查是否 $key == 0.

and if you $stmt is zero-indexed array check if $key == 0.

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