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what is the difference between OLE DB and ODBC data sources?
...ocol in managed code, only using native code to handle the TCP/Named Pipes/etc transmission over the network. For databases that don't have a managed provider of their own, you can use System.Data.OleDb to wrap OLE DB or System.Data.Odbc to wrap ODBC, but it's not recommended.
–...
Sorting Python list based on the length of the string
...ey parameter:
xs.sort(key=lambda s: len(s))
This tells the sort method to order based on whatever the key function returns.
EDIT: Thanks to balpha and Ruslan below for pointing out that you can just pass len directly as the key parameter to the function, thus eliminating the need for a lambda:
xs.s...
What does it mean: The serializable class does not declare a static final serialVersionUID field? [d
... the serialization
(additional fields, removed fields,
change of field order, ...)
That's not correct, and you will be unable to cite an authoriitative source for that claim. It should be changed whenever you make a change that is incompatible under the rules given in the Versioning of Seriali...
List of tables, db schema, dump etc using the Python sqlite3 API
...
You can fetch the list of tables and schemata by querying the SQLITE_MASTER table:
sqlite> .tab
job snmptarget t1 t2 t3
sqlite> select name from sqlite_master where type = 'table';
job
t1
t2
s...
How to find out if an item is present in a std::vector?
...
If your vector is not ordered, use the approach MSN suggested:
if(std::find(vector.begin(), vector.end(), item)!=vector.end()){
// Found the item
}
If your vector is ordered, use binary_search method Brian Neal suggested:
if(binary_searc...
How to check for a valid URL in Java?
... it does not appear to work with newer domains such as .london etc
– V H
Jun 9 '15 at 14:36
how about intr...
Selecting/excluding sets of columns in pandas [duplicate]
...-based method, so duplicate column names will cause issues, and the column order may be changed.
Advantage over drop: you don't create a copy of the entire dataframe when you only need the list of columns. For instance, in order to drop duplicates on a subset of columns:
# may create a copy of t...
Difference between CC, gcc and g++?
...erms of assembly
code generation, available libraries, language features, etc.?
3 Answers
...
Is Big O(logn) log base e?
... big-O notation is usually written showing only the asymptotically highest order of n, so constant coefficients will drop away. Since a different logarithm base is equivalent to a constant coefficient, it is superfluous.
That said, I would probably assume log base 2.
...
Best Practices: Salting & peppering passwords?
... "make sense" isn't enough. Something has to be provable and make sense in order for it to be considered secure. Additionally, it has to be implementable in a maintainable way. The most secure system that can't be maintained is considered insecure (because if any part of that security breaks down, t...