Question

这是我创建的查询：

public string GetOAuthToken(IUser user) {
    if (user  != null) {
        var identity = new ClaimsIdentity(Startup.OAuthOptions.AuthenticationType);
        identity.AddClaim(new Claim(ClaimTypes.Name, user.UserName));
        identity.AddClaim(new Claim(ClaimTypes.NameIdentifier, user.Id));
        AuthenticationTicket ticket = new AuthenticationTicket(identity, new AuthenticationProperties());
        var currentUtc = DateTime.UtcNow;
        ticket.Properties.IssuedUtc = currentUtc;
        ticket.Properties.ExpiresUtc = currentUtc.Add(TimeSpan.FromDays(36600)); //About 100 years
        string AccessToken = Startup.OAuthOptions.AccessTokenFormat.Protect(ticket);
        return AccessToken;
    }
    return "";
}

Answer 1

尝试使用此查询。

> $a 
a
c
> $b
b

Answer 2

首先，您应该使用别名以获得更好的可读性，

检查你是否在$ _GET [id]

中得到了什么

    echo $_GET[id];

然后分配它，（或者你可以设置它，如果你正在使用一个类）

    $fltr = $_GET[id];

然后，尝试使用LEFT JOIN;

    SELECT   b.company,     b.po_box, 
             b.town,        a.address_id, 
             a.attn,        a.create_date,
             a.ref_no,      a.refference, 
             a.letter_body, a.print_date 
    FROM     letter_details AS a LEFT JOIN address_details AS b ON b.id = a.address_id
                                 LEFT JOIN signatories     AS c ON (a.id =c.id) 
    WHERE    a.id='$fltr'

如何在SQL中连接3个表

2 个答案: