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SELECT DISTINCT on one column
...r greater, you can use a CTE with ROW_NUMBER():
SELECT *
FROM (SELECT ID, SKU, Product,
ROW_NUMBER() OVER (PARTITION BY PRODUCT ORDER BY ID) AS RowNumber
FROM MyTable
WHERE SKU LIKE 'FOO%') AS a
WHERE a.RowNumber = 1
...
Why does String.valueOf(null) throw a NullPointerException?
...m 41: Use overloading judiciously
Just because you can overload, doesn't mean you should every time
They can cause confusion (especially if the methods do wildly different things)
Using good IDE, you can check which overload is selected at compile time
With Eclipse, you can mouse-hover on the a...
Python “raise from” usage
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@laike9m: you mean when you are handling exception foo, and want to raise a new exception bar? Then you can use raise bar from foo and have Python state that foo directly caused bar. If you don't use from foo, then Python will still print ...
Difference between id and name attributes in HTML
What is the difference between the id and name attributes? They both seem to serve the same purpose of providing an identifier.
...
Finding duplicate rows in SQL Server
...tatement to grab all of these and the amount of dupes, but also return the ids that are associated with each organization.
...
C++ Const Usage Explanation
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Read this: https://isocpp.org/wiki/faq/const-correctness
The final const means that the function Method3 does not modify the non mutable members of its class.
const int* const means a constant pointer to a constant int: i.e. a pointer that cannot be changed, to an int that cannot be changed: the ...
App Inventor 2 DynamicComponents 拓展：动态创建AI2组件对象 · App Inventor 2 中文网
...不将其保存到已创建的组件列表中，因此它不会关联到 ID。请注意，你无法直接在 Screen 中创建组件，你需要事先在 Screen 中设置布局才能执行此操作。
将已创建组件的 ID...
What is the difference between & and && in Java?
...se since the result will be false
(x != 0) & (1/x > 1) <-- this means evaluate (x != 0) then evaluate (1/x > 1) then do the &. the problem is that for x=0 this will throw an exception.
(x != 0) && (1/x > 1) <-- this means evaluate (x != 0) and only if this is true th...
Avoid duplicates in INSERT INTO SELECT query in SQL Server
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Using NOT EXISTS:
INSERT INTO TABLE_2
(id, name)
SELECT t1.id,
t1.name
FROM TABLE_1 t1
WHERE NOT EXISTS(SELECT id
FROM TABLE_2 t2
WHERE t2.id = t1.id)
Using NOT IN:
INSERT INTO TABLE_2
(id, name)
SELECT t1.id,
...
How do I fix a merge conflict due to removal of a file in a branch?
...dify): res/layout/dialog_item.xml deleted in dialog and modified in HEAD
means that res/layout/dialog_item.xml was deleted in the 'dialog' branch you are merging, but was modified in HEAD (in the branch you are merging to).
So you have to decide whether
remove file using "git rm res/layout/di...