I'm using python 2.7.3 and and Berkeley DB to store data. I didn't find much information about that module, only in python docks. I saw there some function described, but I didn't see instruction on how to delete a record from database. Help please, if you know how to delete a record and is that possible using bsddb ?
According to the documentation:
Once instantiated, hash, btree and record objects support the same methods as dictionaries.
So, you can use del db_object['key'] to delete specific record like a dictionary.
>>> import bsddb
>>> db = bsddb.hashopen('a.db', 'c')
>>> db['a'] = '1'
>>> db.keys()
['a']
>>> del db['a'] # <-----
>>> db.keys()
[]
db_object.pop('key') also works.
>>> db['b'] = '2'
>>> db.keys()
['b']
>>> db.pop('b')
'2'
del, .pop() with non-existing key will raise KeyError or similar exception. If you want ignore non-existing key, use .pop('key', None):
>>> db.pop('b') # This raises an exception
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/usr/lib/python2.7/_abcoll.py", line 497, in pop
value = self[key]
File "/usr/lib/python2.7/bsddb/__init__.py", line 270, in __getitem__
return _DeadlockWrap(lambda: self.db[key]) # self.db[key]
File "/usr/lib/python2.7/bsddb/dbutils.py", line 68, in DeadlockWrap
return function(*_args, **_kwargs)
File "/usr/lib/python2.7/bsddb/__init__.py", line 270, in <lambda>
return _DeadlockWrap(lambda: self.db[key]) # self.db[key]
KeyError: 'b'
>>> db.pop('b', None) # This does not.
>>>
Related
I think the query is correct but still an error.
findQ = {"fromid": wordid}, {"toid":1}
res= self.db.wordhidden.find(findQ)
However, find_one(findQ) works. So I can't find the wrong thing.
I use python 3.6 and pymongo.
Here is my code:
def getallhiddenids(self,wordids,urlids):
l1={}
for wordid in wordids:
findQ = {"fromid": wordid}, {"toid":1}
res= self.db.wordhidden.find(findQ)
for row in res: l1[row[0]]=1
for urlid in urlids:
findQ = {"toid": urlid}, {"fromid":1}
res= self.db.hiddenurl.find(findQ)
This is an error:
Traceback (most recent call last):
File "C:\Users\green\Desktop\example.py", line 9, in <module>
neuralnet.trainquery([online], possible, notspam)
File "C:\Users\green\Desktop\nn.py", line 177, in trainquery
self.setupnetwork(wordids,urlids)
File "C:\Users\green\Desktop\nn.py", line 105, in setupnetwork
self.hiddenids=self.getallhiddenids(wordids,urlids)
File "C:\Users\green\Desktop\nn.py", line 93, in getallhiddenids
res= self.db.wordhidden.find(findQ)
File "C:\Users\green\AppData\Local\Programs\Python\Python36-32\lib\site-
packages\pymongo\collection.py", line 1279, in find
return Cursor(self, *args, **kwargs)
File "C:\Users\green\AppData\Local\Programs\Python\Python36-32\lib\site-
packages\pymongo\cursor.py", line 128, in __init__
validate_is_mapping("filter", spec)
File "C:\Users\green\AppData\Local\Programs\Python\Python36-32\lib\site-
packages\pymongo\common.py", line 400, in validate_is_mapping
"collections.Mapping" % (option,))
TypeError: filter must be an instance of dict, bson.son.SON, or other type
that inherits from collections.Mapping
find_one(findQ) works
The error is because PyMongo find() requires a dictionary or a bson.son object. What you have passed in is a Python tuple object is the form of ({"fromid": wordid}, {"toid":1}). You could correct this by invoking the find() method as below:
db.wordhidden.find({"fromid": wordid}, {"toid": 1})
Technically your invocation of find_one() does not work either. It just that the parameter filter has been altered by find_one(). see find_one() L1006-1008. Which basically format your tuple filter into :
{'_id': ({"fromid": wordid}, {"toid":1}) }
The above would (should) not returned any matches in your collection.
Alternative to what you're doing, you could store the filter parameter into two variables, for example:
filterQ = {"fromid": wordid}
projectionQ = {"toid": 1}
cursor = db.wordhidden.find(filterQ, projectionQ)
I want to check a string - is it an import command? I have tried
# Helper - analyses a string - is it an import string?
"""
fromlike - from foo import bar
classic - import foo
classic_as - import foo as baz
"""
def check_is_import(string):
importname = ''
fromlike = False
classic = False
classic_as = False
if string[0:4] is 'from':
fromlike = True
importname = ''
if not fromlike and (string[0:6] is 'import'):
classic = True
importname = string.split(' ')[1]
if classic:
commandlist = string.split(' ')
if commandlist[2] is 'as':
classic_as = True
importname = commandlist[3]
del commandlist
if fromlike:
return ('fromlike', importname)
elif classic and (not classic_as):
return ('classic', importname)
elif classic_as:
return ('classic_as', importname)
else:
return ('no_import', importname)
but it worked for "fromlike" imports. (Note: I'm not asking "why does this code don't work?", I'm just searching a solution) What code will sure detect all imports? Basically my code takes a slice of the string. If the [0:4] slice equals 'from', the string is a "fromlike import". Else: if the [0:6] slice equals 'import', the string is a "classic import". If it detects 'as', it will find the pseudo-name. This function must return a tuple which contains the import type under index 0 and imported module-name under index 1.
If you want to be sure to handle all Python import forms, have Python do the parsing. Use the ast.parse() function and use the resulting parse tree; you'll either get Import or ImportFrom objects:
| Import(alias* names)
| ImportFrom(identifier? module, alias* names, int? level)
Each alias consists of a name and optional identifier used to import the name as:
-- import name with optional 'as' alias.
alias = (identifier name, identifier? asname)
Note that there can be multiple imports! You either have classic or fromlike imports, and both can import multiple names. Your function needs to return a list of (type, name) tuples. For invalid inputs, raise an exception (ValueError is a good fit here):
import ast
def check_is_import(string):
try:
body = ast.parse(string).body
except SyntaxError:
# not valid Python
raise ValueError('No import found')
if len(body) > 1:
# not a single statement
raise ValueError('Multiple statements found')
if not isinstance(body[0], (ast.Import, ast.ImportFrom)):
raise ValueError('No import found')
type_ = 'classic' if isinstance(body[0], ast.Import) else 'fromlike'
results = []
for alias in body[0].names:
alias_type = type_
if alias.asname:
alias_type += '_as'
results.append((alias_type, alias.asname or alias.name))
return results
The method should probably be renamed to extract_import_names(), as that reflects what it does much better.
Demo:
>>> check_is_import('from foo import bar')
[('fromlike', 'bar')]
>>> check_is_import('import foo')
[('classic', 'foo')]
>>> check_is_import('import foo as baz')
[('classic_as', 'baz')]
>>> check_is_import('from foo import bar, baz as spam, monty as python')
[('fromlike', 'bar'), ('fromlike_as', 'spam'), ('fromlike_as', 'python')]
>>> check_is_import('import foo as baz, baz, spam as ham')
[('classic_as', 'baz'), ('classic', 'baz'), ('classic_as', 'ham')]
>>> check_is_import('invalid python')
Traceback (most recent call last):
File "<stdin>", line 3, in check_is_import
File "/Users/mjpieters/Development/Library/buildout.python/parts/opt/lib/python3.6/ast.py", line 35, in parse
return compile(source, filename, mode, PyCF_ONLY_AST)
File "<unknown>", line 1
invalid python
^
SyntaxError: invalid syntax
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "<stdin>", line 6, in check_is_import
ValueError: No import found
>>> check_is_import('import foo; import bar')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "<stdin>", line 9, in check_is_import
ValueError: Multiple statements found
>>> check_is_import('1 + 1 == 2')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "<stdin>", line 11, in check_is_import
ValueError: No import found
I used biopython to search lineage information from taxonomy database, but it returns empty !
I can used it yesterday(2016/3/15) ! But now I can't used it(2016/03/16)!
The code I used is here,
>>> from Bio import Entrez
>>> Entrez.email = "myemail#gmail.com"
>>> handle = Entrez.esearch(db="Taxonomy", term="Cypripedioideae")
>>> record = Entrez.read(handle)
>>> record["IdList"]
['158330']
>>> record["IdList"][0]
'158330'
>>> handle = Entrez.efetch(db="Taxonomy", id="158330", retmode="xml")
>>> records = Entrez.read(handle)
>>> records[0].keys()
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
IndexError: list index out of range
>>> records
[] #I can't understand why it returns empty today?
I am trying to build/update a dictionary. I have nicknames as keys in temp_dict and looking for ids to add.
Excerpt form my code. I think it is enough for you to see my mistake.
d1 = {u'status': u'ok', u'count': 1, u'data': [{u'nickname': u'45sss', u'account_id': 553472}]}
temp_dict = {}
for key, value in d1.iteritems():
if "data" == key:
for dic2 in value:
x = dic2['nickname']
y = dic2['account_id']
temp_dict[x] = y;
My error:
Traceback (most recent call last):
File "untitled.py", line 36, in <module>
get_PlayerIds_Names_WowpApi_TJ_() #Easy going. Some issues with case letters.
File "g:\Desktop\Programming\WOWP API\functions.py", line 44, in get_PlayerIds_Names_WowpApi_TJ_
check_missing_player_ids(basket)
File "g:\Desktop\Programming\WOWP API\functions.py", line 195, in check_missing_player_ids
temp_dict[x] = y;
TypeError: 'unicode' object does not support item assignment
There are multiple SO entries regarding the same error. But no are connected to such dictionary manipulation.
Most likely you have put unicode string in temp_dict somewhere:
>>> temp_dict = u''
>>> dic2 = {u'nickname': u'45sss', u'account_id': 553472}
>>> x = dic2['nickname']
>>> y = dic2['account_id']
>>> temp_dict[x] = y
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: 'unicode' object does not support item assignment
init it with empty dict and all will work:
>>> temp_dict = {}
>>> temp_dict[x] = y
>>> temp_dict
{u'45sss': 553472}
Why doesn't this work?
for i in [a, b, c]:
i.SetBitmap(wx.Bitmap(VarFiles[str(i)]))
I get:
Traceback (most recent call last):
File "<string>", line 11, in ?
File "codecc.py", line 724, in ?
app = MyApp(0) # stdio to console; nothing = stdio to its own window
File "C:\Program Files (x86)\WorldViz\Vizard30\bin\lib\site-packages\wx-2.8-msw-unicode\wx\_core.py", line 7978, in __init__
self._BootstrapApp()
File "C:\Program Files (x86)\WorldViz\Vizard30\bin\lib\site-packages\wx-2.8-msw-unicode\wx\_core.py", line 7552, in _BootstrapApp
return _core_.PyApp__BootstrapApp(*args, **kwargs)
File "codecc.py", line 719, in OnInit
frame = VFrame(parent=None)
File "codecc.py", line 374, in __init__
i.SetBitmap(wx.Bitmap(VarFiles[str(i)]))
KeyError: "<wx._core.MenuItem; proxy of <Swig Object of type 'wxMenuItem *' at 0x165aeab0> >"
Interestingly, this works:
i.SetBitmap(wx.Bitmap(VarFiles["i"]))
but this doesn't:
i.SetBitmap(wx.Bitmap(VarFiles[i]))
The last one returns an wxpython object with the same name as i, thus breaking the loop. So I need to find a way of returning the name of this object. But i.__name__ doesn't work.
As the traceback says you have a KeyError. Since i is an object when you do str(i) you get "<wx._core.MenuItem; proxy of <Swig Object of type 'wxMenuItem *' at 0x165aeab0> >", such key doesn't exist in a VarFiles container.
It has nothing whatsoever to do with the for loop or the way you write your list.
Break it down using a single case. Where is the error in this?
s = str(a)
v = VarFiles[s]
w = wx.Bitmap(v)
a.SetBitmap(w)
This is how I """"fixed"""" my code:
list_a = [a, b, c]
list_b = ["a", "b", "c"]
[i.SetBitmap(wx.Bitmap(VarFiles[list_b[list_a.index(i)]])) for i in list_a]