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What's the best way to model recurring events in a calendar application?
...ored for a recurring event should always be the end date of the recurrence range (or your platform's "max date" if recurring "forever") and the event duration should be stored separately. This is to ensure a sane way of querying for events later.
Some discussion around generating event instances and...
Unique (non-repeating) random numbers in O(1)?
...SR which period is 1048575 (2^20 - 1) and get next one if number is out of range but this won't be efficient.
– tigrou
Jul 4 '16 at 9:35
1
...
Favourite performance tuning tricks [closed]
...x are matched in the query
Are clustered indices used where appropriate?
range data
WHERE field between value1 and value2
Small Joins are Nice Joins
By default the optimiser will only consider the tables 4 at a time.
This means that in joins with more than 4 tables, it has a good chance of c...
Swapping column values in MySQL
...z set c1 = c1 ^ c2, c2 = c1 ^ c2, c1 = c1 ^ c2;
ERROR 1264 (22003): Out of range value for column 'c1' at row 2
mysql> update z set c1 = c1 + c2, c2 = c1 - c2, c1 = c1 - c2;
ERROR 1264 (22003): Out of range value for column 'c1' at row 3
mysql> select * from z;
+------------+------------+
| c...
What are good grep tools for Windows? [closed]
...r in set
[^class] Inverse class: any one character not in set
[x-y] Range: any characters within the specified range
\x Escape: literal use of metacharacter x
\<xyz Word position: beginning of word
xyz\> Word position: end of word
Example usage: findstr text_to_find ...
Hibernate, @SequenceGenerator and allocationSize
...o optimization before getting query Hibernate tries to assign value in the range of allocationSize and so try to avoid querying database for sequence. But this query will be executed every time if you set it to 1. This hardly makes any difference since if your data base is accessed by some other app...
How to write to an existing excel file without overwriting data (using pandas)?
...17-08','2017-09','2017-10','2017-11','2017-12']
value1 = [x * 5+5 for x in range(len(months))]
df = pd.DataFrame(value1, index = months, columns = ['value1'])
df['value2'] = df['value1']+5
df['value3'] = df['value2']+5
#load workbook that has a chart in it
wb = xw.Book('C:\\data\\bookwithChart.xlsx...
What's wrong with using == to compare floats in Java?
... don't want to compare them using equality, but rather comparison within a range, that is, if the diff of the float to the number you want to compare it to is less than a certain absolute value.
This article on the Register gives a good overview of why this is the case; useful and interesting readi...
Git: How to diff two different files in different branches?
...
You can specify a start and range for git diff to be applied to. The range is indicated with the .. notation.
branch1=somebranch
branch2=someotherbranch
git diff ${branch1}..${branch2} -- file_path
...
Select N random elements from a List in C#
...dom numbers from {0, 1, ..., n-1}
def ChooseRandomSubset(n, k):
for i in range(k):
r = UniformRandom(0, n-i) # May be 0, must be < n-i
q = s.FirstIndexSuchThat( s[q] - q > r ) # This is the search.
s.InsertInOrder(q ? r + q : r + len(s)) # Inserts right before ...