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Iterator Loop vs index loop [duplicate]
.... If your container's size is larger than INT_MAX then obviously you can't convert it to int and the code fails. long long would be safer (especially as it's finally standard). I will never create a vector with 2^63 elements but I might with 2^31.
– Steve Jessop
...
Generate a random number in the range 1 - 10
...: select (trunc(random() * 10) % 10) + 1
The output from trunc has to be converted to INTEGER. But it can be done without trunc. So it turns out to be simple.
select (random() * 9)::INTEGER + 1
Generates an INTEGER output in range [1, 10] i.e. both 1 & 10 inclusive.
For any number (floats)...
What is the best way to auto-generate INSERT statements for a SQL Server table?
...data (Extended characters or Unicode). If needed
you might want to convert the datatypes of character variables in this procedure to their respective unicode counterparts
like nchar and nvarchar
Example 1: To generate INSERT statements for table 'titles':
EXEC sp_generate...
How can I return NULL from a generic method in C#?
... the problem with this is that if you're using this generic method to say, convert a Database object from DbNull to Int and it returns default(T) where T is an int, it'll return 0. If this number is actually meaningful, then you'd be passing around bad data in cases where that field was null. Or a b...
如何查看Oracle用户的SQL执行历史记录？ - 数据库(内核) - 清泛网 - 专注C/...
...privs; 授予用户和其他角色的角色
select * from dba_sys_privs; 授予用户和其他角色的系统权限
select * from dba_tab_privs; 数据库中对象的所有授权
select * from user_role_privs; 查看当前用户的角色
清泛网注...
How to check if any flags of a flag combination are set?
...T : struct
{
CheckIsEnum<T>(true);
long lValue = Convert.ToInt64(value);
long lFlag = Convert.ToInt64(flag);
return (lValue & lFlag) != 0;
}
public static IEnumerable<T> GetFlags<T>(this T value) where T : struct
{
CheckI...
How to resize an Image C#
...< nPercentW)
{
nPercent = nPercentH;
destX = System.Convert.ToInt16((newWidth -
(sourceWidth * nPercent)) / 2);
}
else
{
nPercent = nPercentW;
destY = System.Convert.ToInt16((newHeight -
(sourceHeight * nPercent))...
How to sum all the values in a dictionary?
...alues of the dictionary's keys, a utility function can be helpful:
import sys
def itervalues(d):
return iter(getattr(d, ('itervalues', 'values')[sys.version_info[0]>2])())
sum(itervalues(d))
This is essentially what Benjamin Peterson's six module does.
...
Difference between declaring variables before or in loop?
...
So both look exactly same after compilation. In managed languages code is converted into CL/byte code and at time of execution it's converted into machine language. So in machine language a double may not even be created on the stack. It may just be a register as code reflect that it is a temporary...
How to check Django version
...
For Python:
import sys
sys.version
For Django (as mentioned by others here):
import django
django.get_version()
The potential problem with simply checking the version, is that versions get upgraded and so the code can go out of date. You w...