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Is there a way of making strings file-path safe in c#?
...id chars and an _ for invalid ones
var validFilename = new string(filename.Select(ch => invalidFileNameChars.Contains(ch) ? '_' : ch).ToArray());
To replace invalid characters (and avoid potential name conflict like Hell* vs Hell$):
static readonly IList<char> invalidFileNameChars = Path...
Procedure expects parameter which was not supplied
... data tab [beside layout and Preview tabs] next to the name of the dataset selected, there is another drop down control that lets you change the CommandType. Enjoy!
– SarjanWebDev
Aug 14 '12 at 6:17
...
SQL Server: Make all UPPER case to Proper Case/Title Case
...lare @i int;
declare @c char(1);
if @Text is null
return null;
select @Reset = 1, @i = 1, @Ret = '';
while (@i <= len(@Text))
select @c = substring(@Text, @i, 1),
@Ret = @Ret + case when @Reset = 1 then UPPER(@c) else LOWER(@c) end,
@Reset = case when @c like '[a-zA...
How can I reliably get an object's address when operator& is overloaded?
...on operator that the type comes with.
Thus the f(T&,long) overload is selected (and the Integral Promotion performed).
What happens for any other type ?
Thus the f(T&,long) overload is selected, because there the type does not match the T* parameter.
Note: from the remarks in the fil...
Comparing Dates in Oracle SQL
...r by using the built-in TO_DATE() function, or a date literal.
TO_DATE()
select employee_id
from employee
where employee_date_hired > to_date('31-DEC-95','DD-MON-YY')
This method has a few unnecessary pitfalls
As a_horse_with_no_name noted in the comments, DEC, doesn't necessarily mean D...
Listing all permutations of a string/integer
...(IEnumerable<T> list, int length)
{
if (length == 1) return list.Select(t => new T[] { t });
return GetPermutations(list, length - 1)
.SelectMany(t => list.Where(e => !t.Contains(e)),
(t1, t2) => t1.Concat(new T[] { t2 }));
}
Example:
IEnumerable<...
SQL SERVER: Get total days between two dates
...:09.3312722';
DECLARE @enddate datetime2 = '2009-05-04 12:10:09.3312722';
SELECT DATEDIFF(day, @startdate, @enddate);
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How important is the order of columns in indexes?
I've heard that you should put columns that will be the most selective at the beginning of the index declaration. Example:
...
Left Join With Where Clause
...ring away rows where the left join doesn't succeed. Move it to the join:
SELECT `settings`.*, `character_settings`.`value`
FROM `settings`
LEFT JOIN
`character_settings`
ON `character_settings`.`setting_id` = `settings`.`id`
AND `character_settings`.`character_id` = '1'
...
SQL SELECT speed int vs varchar
...k: A=261MB B=292MB C=322MB
Non-indexed by id: select count(*), select by id: 450ms same on all tables
Insert* one row per TX: B=9ms/record C=9ms/record
Bulk insert* in single TX: B=140usec/record C=180usec/record
Indexed by id, select by id: B=about 2...