Question

好的，我的iPhone模拟器文档中有一个数据库。我现在肯定知道它位于应用程序沙箱中。我的代码中有些东西很时髦。所以我首先得到数据库路径：

-(NSString *)getsynDbPath
{
    NSString* dataBAse = [[NSBundle mainBundle] pathForResource:@"ddd"ofType:@"sqlite"];

    return dataBAse;
}

然后我测试路径：

    NSString *testData;
    testData = [self getsynDbPath];

    NSFileManager * fileManager = [NSFileManager defaultManager];

    BOOL success = [fileManager fileExistsAtPath:testData];

    if (success) {
        NSLog(@"Oh no! There was a big problem!");
    } else {
       //Successfully opened 
        if(sqlite3_open([testData UTF8String], &db)==SQLITE_OK){

            NSLog(@"Raise the roof!");

            //Calling method to loop through columns
            [self listOfCols];

        }


    }

然后我转到一个自定义方法，我遍历数据库中的列：

-(NSArray *)listOfCols{

    NSMutableArray *retval = [[[NSMutableArray alloc]init]autorelease];

    NSString *query = @"SELECT KEY_ID FROM CON_DETAIL";

    sqlite3_stmt *statement;
      //Does not execute
    if (sqlite3_prepare_v2(db, [query UTF8String], -1, &statement, nil)==SQLITE_OK) {

        while (sqlite3_step(statement)==SQLITE_ROW) {

            int key_id = sqlite3_column_int(statement, 0);

            NSLog(@"Key ID: %d", key_id);

            char *nameChars = (char *) sqlite3_column_text(statement, 1);

            NSLog(@"chars %s", nameChars);

            char *cityChars = (char *) sqlite3_column_text(statement, 2);

            NSLog(@"chars %s", cityChars);
       }
    }

    NSLog(@"%s Why '%s' (%1d)", __FUNCTION__, sqlite3_errmsg(db), sqlite3_errcode(db));

    return retval;

}

所以这是我的问题。成功打开数据库后，为什么我收到一条错误消息：no such table: CON_DETAIL？任何帮助表示赞赏。

Answer 1

我认为您必须在文档目录中复制db，然后尝试获取。使用以下功能复制它。

-(void) dbconnect{

    self.databaseName = @”yourdbname.sqlite”;

    // Get the path to the documents directory and append the databaseName
    NSArray *documentPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentsDir = [documentPaths objectAtIndex:0];
    self.databasePath = [documentsDir stringByAppendingPathComponent:self.databaseName];

    // Execute the “checkAndCreateDatabase” function

    [self checkAndCreateDatabase];
}

-(void) checkAndCreateDatabase{
    // Check if the SQL database has already been saved to the users phone, if not then copy it over
    BOOL success;

    // Create a FileManager object, we will use this to check the status
    // of the database and to copy it over if required
    NSFileManager *fileManager = [NSFileManager defaultManager];

    // Check if the database has already been created in the users filesystem
    success = [fileManager fileExistsAtPath:databasePath];

    // If the database already exists then return without doing anything
    if(success) {
        return;
    }
    // If not then proceed to copy the database from the application to the users filesystem

    // Get the path to the database in the application package
    NSString *databasePathFromApp = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:databaseName];

    // Copy the database from the package to the users filesystem
    [fileManager copyItemAtPath:databasePathFromApp toPath:self.databasePath error:nil];

    [fileManager release];

}

注意：如果您没有在应用程序的文档目录中获取数据库，请执行以下操作。转至：目标 - ＆gt; “构建阶段” - ＆gt; “copy bundle Resources”然后在此处添加该特定文件。

之后打电话给你的＆＃34; listOfCols＆＃34;方法

Sqlite DB没有这样的表存在

1 个答案: