php - SELECT 自定义字段和 LEFT JOIN 时的所有字段

Question

我正在从 2 个表中选择数据。

$sql = "SELECT tb1.id, tb2.name FROM tblA tbl1 LEFT JOIN tblB tbl2 ON tb1.id = tbl2.studentID ORDER BY tbl1.id DESC LIMIT 20";
$statement = $con_db->prepare($sql);

我现在的问题是我可以从 tb1 中选择自定义字段以及 tb2 中的所有字段吗？例如

$sql = "SELECT tb1.id, tb1.subject, tb2.(*) FROM ....";

Answer 1

您可以编写如下代码

$sql = "SELECT tb1.id, tb1.subject, tb2.* FROM tblA tbl1 LEFT JOIN tblB tbl2 ON tb1.id = tbl2.studentID ORDER BY tbl1.id DESC LIMIT 20";