我只是想知道,如何检索表中不存在的行并将其返回为NULL?
简要
例如,在下面的代码中,它只返回skill_players中存在的数据,这不是我想要的结果。我想要的结果是,输出现有数据以使其从skill_players获得其值,如果不存在则将值输出为NULL,以便我可以将IFNULL用于以后的目的。
表设计
目前的结果
[Skill Name] | [Value]
TotalStoreRobbed | 8
预期结果
[Skill Name] | [Value]
TotalRape | NULL
TotalBeenRaped | NULL
TotalRob | NULL
TotalBeenRobbed | NULL
TotalStoreRobbed | 8
TotalCuffEscape | NULL
TotalArrest | NULL
TotalBeenArrested | NULL
码
//fetching item data
$query =
"
SELECT
skill.value, type.skill_name
FROM
skills_player AS skill
LEFT JOIN
skills_type AS type
ON
skill.fk_skill_id = type.skill_id
WHERE
skill.fk_user_id = ?
";
if($stmt = $sqlHandle->prepare($query))
{
$stmt->bind_param("i", $acc_ID);
$stmt->execute();
$res = $stmt->get_result();
$skills = null;
if($res->num_rows > 0) {
while($row = $res->fetch_assoc()) {
$skills[] = $row;
print_r($row);
}
}
}
else {
$error = $sqlHandle->errno . ' ' . $sqlHandle->error;
echo $error;
}
谢谢,帕特里克!