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PostgreSQL: Which Datatype should be used for Currency?
... That's not why you avoid floating point. Even Numeric will have rounding errors if you divide by anything that doesn't divide into a power of ten, no matter what precision you use. (Precision of 2 is a Bad Idea anyway... check the docs.)
– Doradus
Jan 9 '18 ...
Unique combination of all elements from two (or more) vectors
... what you are after
> expand.grid(a,b)
Var1 Var2
1 ABC 2012-05-01
2 DEF 2012-05-01
3 GHI 2012-05-01
4 ABC 2012-05-02
5 DEF 2012-05-02
6 GHI 2012-05-02
7 ABC 2012-05-03
8 DEF 2012-05-03
9 GHI 2012-05-03
10 ABC 2012-05-04
11 DEF 2012-05-04
12 GHI 2012-05-04
13 ABC 20...
Writing to output window of Visual Studio
...ied Debug.Write , Console.Write , and Trace.Write . It does not give an error, but it does not print anything either.
13...
How to set request headers in rspec request spec?
...
Yeah. In rspec it raises ndefined method 'header' error for me.
– Евгений Масленков
Oct 19 '17 at 10:11
add a comment
...
Python syntax for “if a or b or c but not all of them”
...'x', 'y', 'z'])
args = parser.parse_args()
if len(args.abc) != 3:
parser.error('expected 3 arguments')
print(args.abc)
Here are some usage examples:
# default case
wim@wim-zenbook:/tmp$ ./three_or_none.py
['x', 'y', 'z']
# explicit case
wim@wim-zenbook:/tmp$ ./three_or_none.py 1 2 3
['1', '2'...
SQL/mysql - Select distinct/UNIQUE but return all columns?
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The query won't parse for me and gives an error: The ranking function "row_number" must have an ORDER BY clause. We need to add order by clause after partition by field1. So the correct query will be select * from ( select *, row_number() over (partiti...
How to escape special characters in building a JSON string?
...parse("'foo'") in your browser console, for example, and observe the SyntaxError: Unexpected token '. The JSON spec is really simple and clear about this. There is no escape sequence in JSON for single quotes, and a JSON string cannot be single-quoted.
– Mark Amery
...
Display number with leading zeros
...
x = "%02d.txt" % i raises TypeError (cannot concatenate 'str' and 'int' objects), but x = "%02d.txt" % (i,) does not. Interesting. I wonder where is that documented
– theta
Nov 5 '12 at 18:10
...
PHP YAML Parsers [closed]
...e wanted something that was "easy to use, fast, unit tested and had clear error messages."
spyc: YAML parser without dependencies
At the time of this writing, the latest versions release dates for the aforementioned libraries and the versions of the YAML spec (1.2 is the latest version) they sup...
Constructor function vs Factory functions
...an't forget new with a class constructor, or the constructor will throw an error.
If you do the instanceof check, it leaves ambiguity as to whether or not new is required. In my opinion, it shouldn't be. You've effectively short circuited the new requirement, which means you could erase drawback #1....