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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...
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...
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...
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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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?...
How to read a file in reverse order?
... while position >= 0:
qfile.seek(position)
next_char = qfile.read(1)
if next_char == "\n":
yield line[::-1]
line = ''
else:
line += next_char
position -= 1
yield line[::-1]
if __n...
Convert an enum to List
How do I convert the following Enum to a List of strings?
2 Answers
2
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mysqldump data only
... you are using --databases ... option
--compact: if you want to get rid of extra comments
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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...
Difference between ref and out parameters in .NET [duplicate]
...nction. It's like if you could write this:
// This is not C#
public (bool, string) GetWebThing(string name, ref Buffer paramBuffer);
// This is C#
public bool GetWebThing(string name, ref Buffer paramBuffer, out string actualUrl);
Here's a more detailed list of the effects of each alternative:
Bef...