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PostgreSQL error 'Could not connect to server: No such file or directory'
...u are on OS X
Here is the fix:
Stop the database
cd /var
sudo rm -r pgsql_socket
sudo ln -s /tmp pgsql_socket
chown _postgres:_postgres pgsql_socket
Restart PostgreSQL (not your computer)
More information is available at "postgresql 9.0.3. on Lion Dev Preview 1".
...
Is the practice of returning a C++ reference variable evil?
...he function, use a smart pointer (or in general, a container):
std::unique_ptr<int> getInt() {
return std::make_unique<int>(0);
}
And now the client stores a smart pointer:
std::unique_ptr<int> x = getInt();
References are also okay for accessing things where you know the...
Postgresql SELECT if string contains
...
You should use 'tag_name' outside of quotes; then its interpreted as a field of the record. Concatenate using '||' with the literal percent signs:
SELECT id FROM TAG_TABLE WHERE 'aaaaaaaa' LIKE '%' || tag_name || '%';
...
Using pg_dump to only get insert statements from one table within database
... as INSERT statements from one specific table within a database using pg_dump in PostgreSQL.
4 Answers
...
What are rvalues, lvalues, xvalues, glvalues, and prvalues?
... three: lvalue, xvalue, prvalue. A Venn diagram would look like this:
______ ______
/ X \
/ / \ \
| l | x | pr |
\ \ / /
\______X______/
gl r
Examples with functions:
int prvalue();
int& lvalue();
int&& xvalue();
But al...
what is the unsigned datatype?
...or unsigned long long int
— float
— double
— long double
— _Bool
— float _Complex
— double _Complex
— long double _Complex
— atomic type specifier
— struct or union specifier
— enum specifier
— typedef name
So in case of unsigned int we can either writ...
How to check if an element is in an array
...ed and work with the first such element,
Then an alternative to contains(_:) as blueprinted Sequence is to first(where:) of Sequence:
let elements = [1, 2, 3, 4, 5]
if let firstSuchElement = elements.first(where: { $0 == 4 }) {
print(firstSuchElement) // 4
// ...
}
In this contrived ex...
set date in input type date
...swered Nov 10 '12 at 14:30
int32_tint32_t
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...
Create a table without a header in Markdown
...command line written in Haskell (supports header-less tables via its simple_tables and multiline_tables extensions)
Flexmark: A parser in Java.
CSS solution
If you're able to change the CSS of the HTML output you can however leverage the :empty pseudo class to hide an empty header and make it loo...
Vertical (rotated) label in Android
... if(Gravity.isVertical(gravity) && (gravity&Gravity.VERTICAL_GRAVITY_MASK) == Gravity.BOTTOM) {
setGravity((gravity&Gravity.HORIZONTAL_GRAVITY_MASK) | Gravity.TOP);
topDown = false;
}else
topDown = true;
}
@Override
protected void onMeasu...