How to access data from HDF5 using hierarchical keys?

I created a repository in HDF5 with hierarchical keys with the following structure

<class 'pandas.io.pytables.HDFStore'>
File path: path-analysis/data/store.h5
/attribution/attr_000000            frame        (shape->[1,5])
/attribution/attr_000001            frame        (shape->[1,5])
/attribution/attr_000002            frame        (shape->[1,5])
/attribution/attr_000003            frame        (shape->[1,5])
.....
/impression/imp_000000              frame        (shape->[1,5])
/impression/imp_000001              frame        (shape->[1,5])
/impression/imp_000002              frame        (shape->[1,5])
/impression/imp_000003              frame        (shape->[1,5])
.....

From what I read in the documentation, I should have access to display and attribution as follows.

store.select('impression')
store.select('attribution')

However, I get an error: TypeError: cannot create storage if the object does not exist or the value is not passed

To add data to the repository, I iterated over my data frames

store.put('impression/imp_' + name, df)

Initially, I used the append api to create the impression of a single table, but it did 80 seconds per frame, and given that I have almost 200 files to process, the append turned out to be too slow.

In comparison, "put" takes less than a second to add to the repository, however it does not allow me to select data later.

, ?

, , ? ?

. .

?

df info

<class 'pandas.core.frame.DataFrame'>
Int64Index: 251756 entries, 0 to 257114
Data columns (total 5 columns):
pmessage_type       251756 non-null object
channel             251756 non-null object
source_timestamp    251756 non-null object
winning_price       251756 non-null int64
ipaddress           251756 non-null object
dtypes: int64(1), object(4)None

pmessage_type, , source_timestamp, WINNING_PRICE, IPAddress   0, , , 1400792099000,1800,99.34.198.9   1, , , 1401587896000,200,99.60.68.61   2, , , 1400873220000,735,65.96.72.183   3, , , 1400768556000,5550,73.182.225.30   4, , , 1401255378000,2099,65.96.72.183   5, , , 1400992770000,88,73.182.225.30   6, , , 1400709948000,290,162.228.58.98   7, , , 1400634607000,1720,162.228.58.98   8, , , 1399201568000,710,108.206.240.138

df.to_csv (...) .

.

data = pd.read_csv(events_csv_file,
                   delimiter='\x01',
                   header=None,
                   names=my_columns.keys(),
                   dtype=my_columns,
                   usecols=my_subset_columns,
                   iterator=True,
                   chunksize=1e6)
df = pd.concat(data)

- :

{'attribution_strategy': object,
 'channel': object,
'flight_uid': object,
'ipaddress': object,
'pixel_id': object,
'pmessage_type': object,
'source_timestamp': object,
'source_unique_id': object,
'unique_id': object,
'user_id': object,
'winning_price': numpy.int64}

. ( - , , )

, pandas,

>>> pandas.__version__
'0.14.0'
>>> 

=====================

,

df = pd.DataFrame({'A': ['foo', 'foo', 'foo', 'foo',
                     'bar', 'bar', 'bar', 'bar',
                     'foo', 'foo', 'foo'],
               'B': ['one', 'one', 'one', 'two',
                     'one', 'one', 'one', 'two',
                     'two', 'two', 'one'],
               'C': ['dull', 'dull', 'shiny', 'dull',
                     'dull', 'shiny', 'shiny', 'dull',
                     'shiny', 'shiny', 'shiny'],
               'D': np.random.randn(11),
               'E': np.random.randn(11),
               'F': np.random.randn(11)})

store = pd.HDFStore('mystore.h5')
store.put('data/01', df)
store.put('data/02', df)

print store

<class 'pandas.io.pytables.HDFStore'>
File path: mystore.h5
/data/01            frame        (shape->[11,6])
/data/02            frame        (shape->[11,6])

store.select('data')

:

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-33-60360d11cde5> in <module>()
----> 1 store.select('data')

/Users/sshegheva/anaconda/envs/numba/lib/python2.7/site-packages/pandas/io/pytables.pyc in select(self, key, where, start, stop, columns, iterator, chunksize, auto_close, **kwargs)
    650         # create the storer and axes
    651         where = _ensure_term(where, scope_level=1)
--> 652         s = self._create_storer(group)
    653         s.infer_axes()
    654 

/Users/sshegheva/anaconda/envs/numba/lib/python2.7/site-packages/pandas/io/pytables.pyc in _create_storer(self, group, format, value, append, **kwargs)
   1157                 else:
   1158                     raise TypeError(
-> 1159                         "cannot create a storer if the object is not existing "
   1160                         "nor a value are passed")
   1161             else:

TypeError: cannot create a storer if the object is not existing nor a value are passed

store.remove('data')
+4

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