while（sqlite3_step（ReturnStatement）== SQLITE_ROW）

Question

我想获取特定城市的记录但是当我调试此代码时，虽然声明不起作用，但它总是在循环之外。

-(NSMutableArray*) getAddressCellLatLong :(NSString *)clinicCity
    {
        NSMutableArray *dataArray = [[NSMutableArray alloc]init];
        NSString * sqlStr=[NSString stringWithFormat:@"select address,phone,mobile,type,latitude,longitude from getclinic where city ='%@'",clinicCity];
        sqlite3_stmt *ReturnStatement = (sqlite3_stmt *) [self getStatement: sqlStr];
        while(sqlite3_step(ReturnStatement) == SQLITE_ROW)
        {
            @try
            {
                ClinicDC* clinic = [[ClinicDC alloc]init];
                NSString *clinicID = [NSString stringWithUTF8String:(char *)sqlite3_column_text(ReturnStatement, 0)];
                 NSString *address = [NSString stringWithUTF8String:(char *)sqlite3_column_text(ReturnStatement, 1)];
                 NSString *phone = [NSString stringWithUTF8String:(char *)sqlite3_column_text(ReturnStatement, 2)];
                 NSString *mobile = [NSString stringWithUTF8String:(char *)sqlite3_column_text(ReturnStatement, 3)];
                 NSString *type = [NSString stringWithUTF8String:(char *)sqlite3_column_text(ReturnStatement, 4)];
                 NSString *city = [NSString stringWithUTF8String:(char *)sqlite3_column_text(ReturnStatement, 5)];
                 NSString *country = [NSString stringWithUTF8String:(char *)sqlite3_column_text(ReturnStatement, 6)];
                 NSString *latitude = [NSString stringWithUTF8String:(char *)sqlite3_column_text(ReturnStatement, 7)];
                 NSString *longitude = [NSString stringWithUTF8String:(char *)sqlite3_column_text(ReturnStatement, 8)];
                clinic.clinicID = [clinicID intValue];
                clinic.cCity = city;
                clinic.cCountry = country;
                clinic.cType = type;
                clinic.cAddress = address;
                clinic.cPhone = phone;
                clinic.cMobile = mobile;
                clinic.cLongitude = longitude;
                clinic.cLatitude = latitude;
                [dataArray addObject:clinic];

            }
            @catch (NSException *ept) {
                NSLog(@"Exception in %s, Reason: %@", __PRETTY_FUNCTION__, [ept reason]);
            }

        }
        return dataArray;

    }