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How to speed up insertion performance in PostgreSQL
...h statement using SQLSetConnectAttr(conn, SQL_ATTR_AUTOCOMMIT, reinterpret_cast<SQLPOINTER>(SQL_AUTOCOMMIT_OFF), 0);
Once all rows have been inserted, commit the transaction using SQLEndTran(SQL_HANDLE_DBC, conn, SQL_COMMIT);. There is no need to explicitly open a transaction.
Unfortunately,...
returning a Void object
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If you want to return null as void you need to cast it in some cases: (Void) null
– Patrick Favre
Mar 29 '16 at 10:04
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How do I check if a list is empty?
... Part 1
The "pythonic" way fails with NumPy arrays because NumPy tries to cast the array to an array of bools, and if x tries to evaluate all of those bools at once for some kind of aggregate truth value. But this doesn't make any sense, so you get a ValueError:
>>> x = numpy.array([0,1]...
What does 'const static' mean in C and C++?
...e you saying const declaration implies static there as well? As in, if you cast const away, and modify the value, all values will be modified?
– Cookie
Mar 26 '14 at 20:44
1
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Random string generation with upper case letters and digits
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If you want to skip the string casting & hyphen replacing, you can just call my_uuid.get_hex() or uuid.uuid4().get_hex() and it will return a string generated from the uuid that does not have hyphens.
– dshap
Apr ...
How to strip all non-alphabetic characters from string in SQL Server?
...nstead of NVARCHAR within his function otherwise, your system will need to cast the string values from VARCHAR to NVARCHAR before it can perform the function which is more expensive. Even with those changes your function still might be faster, but those are a few examples I can see where his functi...
Using Mockito's generic “any()” method
... Please have a look into the API, the class argument is just used for casting, the method still accepts any kind of object! site.mockito.org/mockito/docs/current/org/mockito/…. Use isA() for this case site.mockito.org/mockito/docs/current/org/mockito/….
– thilko
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get list from pandas dataframe column
...then call x.tolist() on to turn them into a Python list. Alternatively you cast it with list(x).
import pandas as pd
data_dict = {'one': pd.Series([1, 2, 3], index=['a', 'b', 'c']),
'two': pd.Series([1, 2, 3, 4], index=['a', 'b', 'c', 'd'])}
df = pd.DataFrame(data_dict)
print(f"DataF...
What is the instanceof operator in JavaScript?
...ript, esp. for some who are used to a language that requires e.g. explicit casting to alter a variable type. As you pointed out, it's very easy to change the type from e.g. primitive int to primitive string.
– moey
Oct 18 '12 at 23:51
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Difference between decimal, float and double in .NET?
...a double/float.
Decimals and Floats/Doubles cannot be compared without a cast whereas Floats and Doubles can. Decimals also allow the encoding or trailing zeros.
float flt = 1F/3;
double dbl = 1D/3;
decimal dcm = 1M/3;
Console.WriteLine("float: {0} double: {1} decimal: {2}", flt, dbl, dcm);
Res...