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How to drop a table if it exists?
...
Is it correct to do the following?
IF EXISTS(SELECT *
FROM dbo.Scores)
DROP TABLE dbo.Scores
No. That will drop the table only if it contains any rows (and will raise an error if the table does not exist).
Instead, for a permanent table you can use
I...
How to remove a Gitlab project?
...
Go to the project page
Select "Settings"
Select the "General" section (you must be in the repository you want to delete to delete it)
If you have enough rights, then at the bottom of the page will be a button for "Advanced settings" (i.e. project s...
Proper way to rename solution (and directories) in Visual Studio
...story of the file. For example, with TortoiseSVN, right click on the file, select TortoiseSVN .. Rename.
In the .sln file, edit all instances of Project1 to be Project2, using a text editor like NotePad.
Restart Visual Studio, and everything will work as before, but with the project in a different ...
SQL Joins Vs SQL Subqueries (Performance)?
...e result i was looking for was 739 elements.
My query at first was this:
SELECT p.id,
p.fixedId,
p.azienda_id,
p.categoria_id,
p.linea,
p.tipo,
p.nome
FROM prodotto p
WHERE p.azienda_id = 2699 AND p.anno = (
SELECT MAX(p2.anno)
FROM prodotto p2
WHERE p2.fixed...
Add support library to Android Studio project
...oject Structure (Press F4 on PC and Command+; on MAC) on your project).
2.Select Modules on the left pane.
3.Choose your project and you will see Dependencies TAB above the third Column.
4.Click on the plus sign in the bottom. Then a tree-based directory chooser dialog will pop up, navigate to yo...
Visual Studio 2013 hangs when opening a solution
...| Attach to Process...
In the list of processes locate devenv.exe.
Click Select... and explicitly choose 'Native' and 'Managed' code.
Click OK and OK to close Select dialog and Attach to Process dialog.
Go back to the first instance of VS and repro the hang.
Upon the hang, control should go to ...
How to update column with null value
...Hello');
UPDATE your_table
SET your_column = NULL
WHERE some_id = 1;
SELECT * FROM your_table WHERE your_column IS NULL;
+---------+-------------+
| some_id | your_column |
+---------+-------------+
| 1 | NULL |
+---------+-------------+
1 row in set (0.00 sec)
...
Cleanest way to build an SQL string in Java
...uild an SQL string to do database manipulation (updates, deletes, inserts, selects, that sort of thing) - instead of the awful string concat method using millions of "+"'s and quotes which is unreadable at best - there must be a better way.
...
JavaScript get clipboard data on paste event (Cross browser)
...vent using a keypress event handler
In that handler, save the current user selection, add a textarea element off-screen (say at left -1000px) to the document, turn designMode off and call focus() on the textarea, thus moving the caret and effectively redirecting the paste
Set a very brief timer (say...
How do I create a new class in IntelliJ without using the mouse?
...with arrow keys, then press Alt+Insert.
Another useful shortcut is View | Select In (Alt+F1), Project (1), then Alt+Insert to create a class near the existing one or use arrow keys to navigate through the packages.
And yet another way is to just type the class name in the existing code where you w...