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MySQL - Rows to Columns
...temvalue |
+--------+----------+-----------+
| 1 | A | 10 |
| 1 | B | 3 |
| 2 | A | 9 |
| 2 | C | 40 |
+--------+----------+-----------+
This will be our goal, the pretty pivot table:
select * from history_itemvalue_piv...
str performance in python
...
105
'%s' % 100000 is evaluated by the compiler and is equivalent to a constant at run-time.
>&g...
What does the caret operator (^) in Python do?
...y one) of the operands (evaluates to) true.
To demonstrate:
>>> 0^0
0
>>> 1^1
0
>>> 1^0
1
>>> 0^1
1
To explain one of your own examples:
>>> 8^3
11
Think about it this way:
1000 # 8 (binary)
0011 # 3 (binary)
---- # APPLY XOR ('vertically')
10...
How to match a String against string literals in Rust?
...
101
You can do something like this:
match &stringthing[..] {
"a" => println!("0"),
...
When should I use Struct vs. OpenStruct?
...
180
With an OpenStruct, you can arbitrarily create attributes. A Struct, on the other hand, must ha...
Array initializing in Scala
... |
edited Jun 1 '11 at 12:09
answered Oct 7 '10 at 11:11
Va...
How to add leading zeros?
...f digits to begin with, so let's try a harder example of making powers of 10 width 8 too.
anim <- 25499:25504
x <- 10 ^ (0:5)
paste (and it's variant paste0) are often the first string manipulation functions that you come across. They aren't really designed for manipulating numbers, but ...
What are the advantages of using nullptr?
... handle nullptr argument!!!
1. In C++, NULL is defined as #define NULL 0, so it is basically int, that is why f(int) is called.
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