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Why unsigned integer is not available in PostgreSQL?
...l.org/docs/9.4/static/sql-createdomain.html
CREATE DOMAIN name [ AS ] data_type
[ COLLATE collation ]
[ DEFAULT expression ]
[ constraint [ ... ] ]
where constraint is:
[ CONSTRAINT constraint_name ]
{ NOT NULL | NULL | CHECK (expression) }
Domain is like a type but with an addition...
Python Pandas merge only certain columns
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Hmmm ... I tried using this to merge column 'Unique_External_Users' from df2 to df1 but got an error ... "None of [Index(['U', 'n', 'i', 'q', 'u', 'e', '', 'E', 'x', 't', 'e', 'r', 'n', 'a',\n 'l', '', 'U', 's', 'e', 'r', 's'],\n dtype='object')] are in the [column...
Determine Whether Two Date Ranges Overlap
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Proof:
Let ConditionA Mean that DateRange A Completely After DateRange B
_ |---- DateRange A ------|
|---Date Range B -----| _
(True if StartA > EndB)
Let ConditionB Mean that DateRange A is Completely Before DateRange B
|---- DateRange A ...
How to explicitly discard an out argument?
...ublic void PrintXCoordinate(Point p)
{
p.GetCoordinates(out int x, out _); // I only care about x
WriteLine($"{x}");
}
Source: https://blogs.msdn.microsoft.com/dotnet/2017/03/09/new-features-in-c-7-0/
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How do I perform a Perl substitution on a string while keeping the original?
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I was wondering if something like my $new = $_ for $old =~ s/foo/bar; would work?
– Benoit
Apr 30 '14 at 17:11
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What's the most elegant way to cap a number to a segment? [closed]
...a-library" answer but just in case you're using Lodash you can use .clamp:
_.clamp(yourInput, lowerBound, upperBound);
So that:
_.clamp(22, -10, 10); // => 10
Here is its implementation, taken from Lodash source:
/**
* The base implementation of `_.clamp` which doesn't coerce arguments.
*
* ...
Oracle query to fetch column names
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The Oracle equivalent for information_schema.COLUMNS is USER_TAB_COLS for tables owned by the current user, ALL_TAB_COLS or DBA_TAB_COLS for tables owned by all users.
Tablespace is not equivalent to a schema, neither do you have to provide the tablespace name....
How do you specify that a class property is an integer?
...// Helper for generating Opaque types.
type Opaque<T, K> = T & { __opaque__: K };
// 2 opaque types created with the helper
type Int = Opaque<number, 'Int'>;
type ID = Opaque<number, 'ID'>;
// using our types to differentiate our properties even at runtime
// they are still j...
How to write into a file in PHP?
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You can use a higher-level function like:
file_put_contents($filename, $content);
which is identical to calling fopen(), fwrite(), and fclose() successively to write data to a file.
Docs: file_put_contents
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Python Regex - How to Get Positions and Values of Matches
...the span & group are indexed for multi capture groups in a regex
regex_with_3_groups=r"([a-z])([0-9]+)([A-Z])"
for match in re.finditer(regex_with_3_groups, string):
for idx in range(0, 4):
print(match.span(idx), match.group(idx))
...