我有两个带有列的表recipes_sa
:
recipes_id recipes_name recipes_chef
---------- ------------ ------------
和chefs_sa
中的列:
chefs_id chefs_name
-------- ----------
我想使用INNER JOIN
和LIMIT
我做了以下功能:
function getLimitJoinData($data, $tbls, $ids, $abr, $type, $limit) {
$dataToSelect = implode($data, ',');
$q = "SELECT $dataToSelect";
$q.= " FROM (SELECT * FROM $tbls[0] LIMIT $limit) $abr";
for ($i=1; $i < count($tbls); $i++) {
$q .= " ".$type." JOIN ". $tbls[$i] ." ON " . $abr.'.recipes_chef' .' = '. $ids[$i-1][0];
}
}
查询就像这样
SELECT chefs_sa.chefs_name,
recipes_sa.recipes_name
FROM (SELECT * FROM recipes_sa LIMIT 8) rec
INNER JOIN chefs_sa ON rec.recipes_chef = chefs_sa.chefs_id
但是当我运行查询时,出现以下警告:
警告:PDO :: query():SQLSTATE [42S22]:找不到列:1054未知列'recipes_sa.recipes_name' 我不明白为什么
我在recipes_name
表中有列recipes_sa
,据我所知,数据库首先运行“ 内部查询”(有限制的查询),然后运行怎么找不到配方名称列!!
答案 0 :(得分:3)
另一种方法是按配方排序,然后限制为最新的8,而不是使用子查询:
number = 2
答案 1 :(得分:3)
您已别名recipes_sa
AS rec
。使用以下内容:
SELECT chefs_sa.chefs_name,
rec.recipes_name
FROM (SELECT * FROM recipes_sa LIMIT 8) rec
INNER JOIN chefs_sa ON rec.recipes_chef = chefs_sa.chefs_id