提供问题的一般摘要。
DROP TABLE IF EXISTS student;
CREATE TABLE student
(student_id SERIAL PRIMARY KEY
,tutor_id INT NOT NULL
);
INSERT INTO student VALUES
(1,2),
(2,1),
(3,3);
DROP TABLE IF EXISTS tutor;
CREATE TABLE tutor
(tutor_id INT NOT NULL
,subject_id INT NOT NULL
,PRIMARY KEY(tutor_id,subject_id)
);
INSERT INTO tutor VALUES
(1,3),
(2,4),
(4,1);
DROP TABLE IF EXISTS subject;
CREATE TABLE subject
(subject_id SERIAL PRIMARY KEY
,subject VARCHAR(12) NOT NULL UNIQUE
);
INSERT INTO subject VALUES
(1,'Maths'),
(2,'Science'),
(4,'English');
SELECT *
FROM student x
LEFT
JOIN tutor y
ON y.tutor_id = x.tutor_id
LEFT
JOIN subject z
ON z.subject_id = y.subject_id
WHERE z.subject_id IS NULL;
+------------+----------+----------+------------+------------+---------+
| student_id | tutor_id | tutor_id | subject_id | subject_id | subject |
+------------+----------+----------+------------+------------+---------+
| 2 | 1 | 1 | 3 | NULL | NULL |
| 3 | 3 | NULL | NULL | NULL | NULL |
+------------+----------+----------+------------+------------+---------+
):4.2.1 cordova -v
):7.1.4 使用:
cordova platform ls
我想显示带有自定义声音的通知
位于this.localNotifications.schedule({
id: 1,
text: 'You have arrived',
sound: 'file://assets/sounds/alerts/arrival.mp3',
data: { secret: 'hellloo' },
vibrate: true
});
我尝试了所有可能的文件路径(我认为),但是它仍然播放默认的Samsung Galaxy s8通知声音。
Logcat输出:
src/assets/sounds/alerts/...
我注意到正在记录“ sound = null”,这有点奇怪。 预先感谢。
以诚挚的问候,
约拿