我有以下数据-
Code1 Code2
G01621 E04621
我想显示在代码1中但不在代码2中的所有代码。
我编写了以下SQL，但返回的数据不正确-
select * from codes c1
left join codes c2
on lower(c1.code1) = lower(c2.code2)
where c2.code2 is null
答案 0 :(得分：1)
您可以使用not exists：
select c.code1
from codes c
where not exists (select 1
from codes c2
where lower(c2.code2) = lower(c.code1)
);
答案 1 :(得分：0)
使用trim()函数
select * from codes c1
left join codes c2
on trim(lower(c1.code1)) = trim(lower(c2.code2))
where c2.code1 is null;
答案 2 :(得分：0)
使用var video = document.querySelector("#cameraVideo");
var mode = "rear";
var mediaRecorder;
var chunks = [];
if (navigator.mediaDevices.getUserMedia) {
navigator.mediaDevices.getUserMedia({video: { facingMode: "environment" } }).then(function (stream) {
video.srcObject = stream;
mediaRecorder = new MediaRecorder(stream);
}).catch(function (err0r) {
alert("Something went wrong!");
});
}
$(".camera").find(".take").on("touchstart mousedown", function() {
mediaRecorder.start();
mediaRecorder.ondataavailable = function(ev) {
chunks.push(ev.data);
}
});
$(".camera").find(".take").on("touchend mouseup", function() {
mediaRecorder.stop();
mediaRecorder.onstop = (ev)=>{
var blob = new Blob(chunks, { 'type' : 'video/mp4' });
chunks = [];
var videoURL = webkitURL.createObjectURL(blob);
if(video.srcObject) video.srcObject.getTracks().forEach(t => t.stop());
var reader = new FileReader();
reader.readAsDataURL(blob);
reader.onloadend = function() {
document.getElementById("savevideo").src = reader.result;
document.getElementById("savevideo").play();
}
}
});
：
except