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'id' is a bad variable name in Python
...ion Descriptive: Naming Styles :
single_trailing_underscore_ : used by convention to avoid conflicts
with Python keyword, e.g.
Tkinter.Toplevel(master, class_='ClassName')
So, to answer the question, an example that applies this guideline is:
id_ = 42
Including the trailing und...
Postgresql aggregate array
...arks
FROM student s
LEFT JOIN Grade g ON g.Student_id = s.Id
GROUP BY s.Id
By the way, if you are using Postgres 9.1, you don't need to repeat the columns on SELECT to GROUP BY, e.g. you don't need to repeat the student name on GROUP BY. You can merely GROUP BY on primary key. If you remov...
django order_by query set, ascending and descending
How can I order by descending my query set in django by date?
11 Answers
11
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What is the meaning of id?
... from NSObject. The compiler will allow you to assign an object referenced by type id to any object type, assign any object type to id, as well as send it any message (that the compiler has seen) without warning.
share
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How to create and handle composite primary key in JPA
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Is it possible to use @Generatedvalue for Id's by EmbeddedId
– Kayser
Oct 24 '12 at 8:15
1
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Show dialog from fragment?
... now the preferred method. You can avoid referencing the Activity entirely by using the putFragment and getFragment methods of FragmentManager, allowing the DialogFragment to report back directly to the calling fragment (even after orientation changes).
– Dave
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How to generate a git patch for a specific commit?
...
This command (as suggested already by @Naftuli Tzvi Kay):
git format-patch -1 HEAD
Replace HEAD with specific hash or range.
will generate the patch file for the latest commit formatted to resemble UNIX mailbox format.
-<n> - Prepare patches from...
How to combine class and ID in CSS selector?
...ng an id and a class on one element, but you shouldn't need to identify it by both for one rule. If you really want to you can do:
#content.sectionA{some rules}
You don't need the div in front of the ID as others have suggested.
In general, CSS rules specific to that element should be set with t...
Get current AUTO_INCREMENT value for any table
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You can get all of the table data by using this query:
SHOW TABLE STATUS FROM `DatabaseName` WHERE `name` LIKE 'TableName' ;
You can get exactly this information by using this query:
SELECT `AUTO_INCREMENT`
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_SCHE...
Oracle “Partition By” Keyword
Can someone please explain what the partition by keyword does and give a simple example of it in action, as well as why one would want to use it? I have a SQL query written by someone else and I'm trying to figure out what it does.
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