在表sqlite中选择数据记录只有一个对象返回

Question

我有一个问题，当我选择用户名返回只有一个对象和表包含所有用户名如何解决这个我尝试通过数据库管理器选择，我发现该查询SQL statment是正确

- (NSMutableArray*) FindAccounts 
    { 
    ///database 
    NSString *docsDir; 
    NSArray *dirPaths; 
    // Get the documents directory 
    dirPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); 
    docsDir = [dirPaths objectAtIndex:0]; 
    // Build the path to the database file 
    databasePath = [[NSString alloc] initWithString: [docsDir stringByAppendingPathComponent: @"TRIAL.sqlite"]]; 
    NSFileManager *filemgr = [NSFileManager defaultManager]; 
    sqlite3_stmt *statement; 
    const char *dbpath = [databasePath UTF8String]; 
    if (sqlite3_open(dbpath, &contactDB) == SQLITE_OK) 
    { 
    NSString *querySQL = [NSString stringWithFormat:@"SELECT USERNAME,TYPE FROM CONTNEW"]; 
    const char *query_stmt = [querySQL UTF8String]; 
    NSMutableArray *resultArray = [[NSMutableArray alloc]init]; 
    if (sqlite3_prepare_v2(contactDB,query_stmt, -1, &statement, NULL) == SQLITE_OK) 
    { 
    if (sqlite3_step(statement) == SQLITE_ROW) 
    { 
    NSString *USERS = [[NSString alloc] initWithUTF8String:(const char *)  sqlite3_column_text(statement, 0)]; 
    [resultArray addObject:USERS]; 
    return resultArray; 
    } 
    else{ 
    NSLog(@"Not found"); 
    return nil; 
    } 
    sqlite3_reset(statement); 
    } 
    } 
    return nil; 
    } 

Answer 1

OK，试试这个（注意，没有太多的错误报告）：

- (NSMutableArray*) FindAccounts 
{ 
    NSString *docsDir = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0]; 
    NSString *databasePath = [docsDir stringByAppendingPathComponent:@"TRIAL.sqlite"]; 
    sqlite3_stmt *statement; 
    // I assume contactDB is an instance variable? 
    if (!contactDB && 
     sqlite3_open([databasePath UTF8String], &contactDB) != SQLITE_OK) { 
     NSLog(@"Failed to open database"); 
     return nil; 
    } 

    NSString *querySQL = @"SELECT USERNAME,TYPE FROM CONTNEW ORDER BY USERNAME"; 
    NSMutableArray *resultArray = [NSMutableArray new]; 
    if (sqlite3_prepare_v2(contactDB, [querySQL UTF8String], -1, &statement, NULL) == SQLITE_OK) 
    { 
     while (sqlite3_step(statement) == SQLITE_ROW) 
     { 
      NSString *username = @(sqlite3_column_text(statement, 0)); 
      [resultArray addObject:username]; 
     } 
     sqlite3_reset(statement); 
    } 
    return resultArray; 
}