如何在objc中使用带有多个where值的select语句？

Question

我认为这不是正确的格式，因为控制台在 nslog 检索所有权结果时停止。我需要解决这个问题吗？创建一个临时表来存储 qr 的 where 然后搜索 where 用户？还是我可以更新我的 sql 语句？

[database executeQuery:@"select * from ownership where qrcode = ? and user = ?;", ktQRcode, userktid];

NSLog(@"retrieving ownership results through qrcode and userid");

while ([results next]) {

    OWNERSHIP *ktownership = [OWNERSHIP new];

    ktownership.uniqueIDownership = [results intForColumn:@"id"];

    ktownership.user = [results intForColumn:@"user"];

    ktownership.qrcode = [results intForColumn:@"qrcode"];

    ktownership.create_at = [results dateForColumn:@"create_at"];

    [foundOwnership addObject:ktownership];

    ownershipcount = [foundOwnership count];

    NSLog(@"addnewownership count: %lu", foundOwnership.count);

    NSLog(@"addnewownership Array: %@", foundOwnership);

Answer 1

您没有向我们展示您分配results 变量的位置。您还应该检查失败，例如：

FMResultSet *results = [database executeQuery:@"select * from ownership where qrcode = ? and user = ?;", ktQRcode, userktid];

if (!results) {
    NSLog(@"select error: %@", [database lastErrorMessage]);
} else {
    NSLog(@"retrieving ownership results through qrcode and userid");
}

while ([results next]) {

    OWNERSHIP *ktownership = [OWNERSHIP new];

    // the rest of your code here
}