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How to printf uint64_t? Fails with: “spurious trailing ‘%’ in format”
...s towards a locale independent and/or locale selectable version of std::to_string(). The cppreference page still link only to std::to_chars(), which is not really what people need. I wonder if fmt and/or c++20 deal with it or not yet.
– ceztko
Nov 28 '19 at 0:2...
Why use multiple columns as primary keys (composite primary key)
...going to, in general, perform more poorly than a surrogate key'. Often an extra query is required to get the surrogate key of a relationship when you consider it. At which point it's a full extra round trip slower performance wise.
– ttugates
Apr 19 '19 at 20...
Is there a performance difference between a for loop and a for-each loop?
...ts.
First, the classic way of looping through List:
for (int i=0; i < strings.size(); i++) { /* do something using strings.get(i) */ }
Second, the preferred way since it's less error prone (how many times have YOU done the "oops, mixed the variables i and j in these loops within loops" thing?...
Why charset names are not constants?
...
The simple answer to the question asked is that the available charset strings vary from platform to platform.
However, there are six that are required to be present, so constants could have been made for those long ago. I don't know why they weren't.
JDK 1.4 did a great thing by introducing t...
ruby on rails f.select options with custom attributes
...
def options_for_select(container, selected = nil)
return container if String === container
container = container.to_a if Hash === container
selected, disabled = extract_selected_and_disabled(selected)
options_for_select = container.inject([]) do |options, element|
html_attrib...
Multi-statement Table Valued Function vs Inline Table Valued Function
...urned only tables formatted like 'C_______' then the outer query did a sub-string and int conversion. ie Cast(Substring(2, 2) as int) as CompNo. All looks good except that sql server decided to put my Cast function before the results were filtered and so I get a mind scrambling conversion error. A...
mysqldump data only
... you are using --databases ... option
--compact: if you want to get rid of extra comments
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Return 0 if field is null in MySQL
...) returns expr1; otherwise it returns expr2. IFNULL() returns a numeric or string value, depending on the context in which it is used.
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Convert an enum to List
How do I convert the following Enum to a List of strings?
2 Answers
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How do I perform HTML decoding/encoding using Python/Django?
I have a string that is HTML encoded:
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