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What is the difference between UNION and UNION ALL?
...want the duplicates (especially when developing reports).
UNION Example:
SELECT 'foo' AS bar UNION SELECT 'foo' AS bar
Result:
+-----+
| bar |
+-----+
| foo |
+-----+
1 row in set (0.00 sec)
UNION ALL example:
SELECT 'foo' AS bar UNION ALL SELECT 'foo' AS bar
Result:
+-----+
| bar |
+---...
Select DISTINCT individual columns in django?
I'm curious if there's any way to do a query in Django that's not a " SELECT * FROM... " underneath. I'm trying to do a " SELECT DISTINCT columnName FROM ... " instead.
...
How to quickly open a file in Visual Studio 2012
...
This would be perfect if it would clear the selection after opening the file. As it is, having to manually clear it with the mouse makes it nearly useless. :-( I want a sublime text style onebox open file/search symbol/goto line addin for VS.
– Ch...
PHP PDO returning single row
...
$dbh = new PDO(" --- connection string --- ");
$stmt = $dbh->prepare("SELECT name FROM mytable WHERE id=4 LIMIT 1");
$stmt->execute();
$row = $stmt->fetch();
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Error when trying to obtain a certificate: The specified item could not be found in the keychain
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I solved it. Ensure you are in the "Certificates" section and you select "Apple Worldwide Developer Relations Certification Authority" before requesting a certificate.
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Comparing Dates in Oracle SQL
...r by using the built-in TO_DATE() function, or a date literal.
TO_DATE()
select employee_id
from employee
where employee_date_hired > to_date('31-DEC-95','DD-MON-YY')
This method has a few unnecessary pitfalls
As a_horse_with_no_name noted in the comments, DEC, doesn't necessarily mean D...
How to select Python version in PyCharm?
...ntegrated. The issue is as diagnosed above, you have the wrong interpreter selected.
The exact method to fix this for any given project is to go to Project Settings...Project and adjust the Project SDK. You can add a New Project SDK if you don't have Python 3 added by navigating to the python3 bina...
INNER JOIN ON vs WHERE clause
...ed is a cartesian product of the tables to which a filter is applied which selects only those rows with joining columns matching.
It's easier to see this with the WHERE syntax.
As for your example, in MySQL (and in SQL generally) these two queries are synonyms.
Also note that MySQL also has a STR...
Can I write a CSS selector selecting elements NOT having a certain class or attribute?
I would like to write a CSS selector rule that selects all elements that don't have a certain class. For example, given the following HTML:
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Overloaded method selection based on the parameter's real type
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I expect the method selection to take
in consideration the real (not the
declared) parameter type. Am I missing
something?
Yes. Your expectation is wrong. In Java, dynamic method dispatch happens only for the object the method is called ...