Question

我在我的应用程序中通过FMDB使用SQLite，并且它在过去几个月一直在所有XCode模拟器上工作，但是，当我现在在实际设备上进行测试时，我似乎遇到了问题当我尝试插入时。

我得到的错误是：

error domain = fmdatabase code = 14＆＃34;无法打开数据库文件＆＃34; UserInfo = 0x178665340 {NSLocalizedDescription =无法打开数据库文件}

这是我的代码：

我将所有FMDB内容包装在我创建的Helper类中：

_lHelper = [[BTRLocationsDatabaseHelper alloc] init];
    self.dbString = [_lHelper checkTableAndCreate:TABLE_LOCAL_LOCATIONS];

那叫：

  NSString *const LOCATIONS_DB_PATH = @"/Library/Caches/myapp_locations.db";
  NSString *const TABLE_LOCAL_LOCATIONS = @"locallocations";
 NSString *const TABLE_FAVORITE_LOCATIONS = @"favoritelocations";

  - (instancetype)init {
self = [super init];

if(self) {

    _db = [FMDatabase databaseWithPath:LOCATIONS_DB_PATH];

    if(![_db open]) {
        NSLog(@"Error opening myapp_locations database");
    }
}

return self;
}

-(NSString *)checkTableAndCreate:(NSString *)table {
NSString *errorString = @"";
FMResultSet *rs = [self.db executeQuery:@"select DISTINCT tbl_name from sqlite_master where tbl_name = ?", table];
[rs next];
BOOL errors = NO;
if([rs hasAnotherRow]) {
    // table exists - I think -> So here we would do nothing
    NSLog(@"locallocations table existed");
} else {
    NSLog(@"locallocations table does not exist");

    // table does not exist - I think -> So here we would create the table
    if([table isEqualToString:TABLE_LOCAL_LOCATIONS]) {
        NSLog(@"Creating a new locallocations table");
        BOOL success = [self.db executeUpdate:@"create table locallocations .....)"];

        if(!success) {
            errors = YES;
            NSString *err = [NSString stringWithFormat:@"%@", [self.db lastError]];
            [errorString stringByAppendingString:err];
            NSLog(@"Error create table locallocations: %@", [self.db lastError]);
        }
    }

}

FMResultSet *rsFavorites = [self.db executeQuery:@"select DISTINCT tbl_name from sqlite_master where tbl_name = ?", @"favoritelocations"];
[rsFavorites next];
BOOL errorsFavorites = NO;
if([rsFavorites hasAnotherRow]) {
    // table exists - I think -> So here we would do nothing
    NSLog(@"favoritelocations table existed");
} else {
    NSLog(@"favoritelocations table does not exist");
    NSLog(@"Creating a new favoritelocations table");
    // table does not exist - I think -> So here we would create the table
    BOOL success = [self.db executeUpdate:@"create table favoritelocations ...."];

    if(!success) {
        errorsFavorites = YES;
        NSString *err = [NSString stringWithFormat:@", %@", [self.db lastError]];
        [errorString stringByAppendingString:err];
        NSLog(@"Error create table favoritelocations: %@", [self.db lastError]);
    }
}


// Down here we would do logic for adding new columns if we ever need them - if errors is false

return errorString;
}

在完成之后我打印出errorString并且它是空的，这让我相信表创建工作。

然后我稍后尝试在Helper类中调用此方法：

  -(NSString *)insertFavoriteLocation:(BTRLocation *)location
                   userId:(int)userId {
NSMutableDictionary *dictionaryArgs = [NSMutableDictionary dictionary];
//... just adding stuff to my dictionary

BOOL result = [self.db executeUpdate:@"insert into favoritelocations ....];

NSError *error = [self.db lastError];
NSString *errorString = [NSString stringWithFormat:@"%@", error];
return errorString;

}

运行之后我打印出errorString，它说上面粘贴的错误，错误代码14无法打开数据库文件。

所以这在模拟器上完美运行，可能导致它无法在设备上运行（iPhone 5s具体，但这是我尝试过的唯一设备）。

谢谢！

修改

    NSString* path = [NSSearchPathForDirectoriesInDomains(
                                                          NSLibraryDirectory, NSUserDomainMask, YES) objectAtIndex:0];

解决方案：

对于那些关心的人，这就是我最终修复它的方式：

修改了init方法：

  NSString *cachePath = [NSSearchPathForDirectoriesInDomains(
                                                          NSCachesDirectory, NSUserDomainMask, YES) objectAtIndex:0];
    NSString *dbPath =  [cachePath stringByAppendingPathComponent:@"myapp_locations.db"];
    _db = [FMDatabase databaseWithPath:dbPath];

iOS：仅在设备上插入时出现FMDB错误

0 个答案: