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How can I clear an HTML file input with JavaScript?
...it does seem reasonable to provide a simple mechanism for clearing already selecting output. I tried using an empty string but it did not work in all browsers, NULL worked in all the browsers I tried (Opera, Chrome, FF, IE11+ and Safari).
EDIT:
Please note that setting to NULL works on all browser...
What is a handle in C++?
I have been told that a handle is sort of a pointer, but not, and that it allows you to keep a reference to an object, rather than the object itself. What is a more elaborate explanation?
...
What's the difference between comma separated joins and join on syntax in MySQL? [duplicate]
...LL
)
Following query will give me all columns and rows from both tables
SELECT
*
FROM table1, table2
Following query will give me columns from first table with table alias called 'table2'
SELECT
*
FROM table1 table2
If you mistakenly forget comma in comma-separated join, second table...
Update a record without first querying?
...his in EF Core, but the following ensures an UPDATE without having to do a SELECT (tested with EF Core 2 and JET on the .NET Framework 4.6.2):
Ensure your model does not have IsRequired properties
Then use the following template (in VB.NET):
Using dbContext = new MyContext()
Dim beweg...
How do you implement a class in C? [closed]
Assuming I have to use C (no C++ or object oriented compilers) and I don't have dynamic memory allocation, what are some techniques I can use to implement a class, or a good approximation of a class? Is it always a good idea to isolate the "class" to a separate file? Assume that we can preallocate t...
VIM Ctrl-V Conflict with Windows Paste
...nce CTRLV is used to paste, you can't use it to start a blockwise Visual
selection. You can use CTRLQ instead. You can also use CTRLQ in Insert
mode and Command-line mode to get the old meaning of CTRLV. But CTRLQ
doesn't work for terminals when it's used for control flow.
...
Spark java.lang.OutOfMemoryError: Java heap space
... suggestions:
If your nodes are configured to have 6g maximum for Spark (and are leaving a little for other processes), then use 6g rather than 4g, spark.executor.memory=6g. Make sure you're using as much memory as possible by checking the UI (it will say how much mem you're using)
Try using more ...
How to rethrow the same exception in SQL Server
...lare @ErrorMessage nvarchar(max), @ErrorSeverity int, @ErrorState int;
select @ErrorMessage = ERROR_MESSAGE() + ' Line ' + cast(ERROR_LINE() as nvarchar(5)), @ErrorSeverity = ERROR_SEVERITY(), @ErrorState = ERROR_STATE();
if @@trancount > 0 rollback transaction;
raiserror (@ErrorMessa...
Composer Warning: openssl extension is missing. How to enable in WAMP
... Answer also works for EasyPHP (right-click system tray EasyPHP icon, select Configuration | PHP, which opens php.ini in Notepad, search for openssl, uncomment the line)
– stifin
Jan 21 '15 at 12:57
...
Is there a REAL performance difference between INT and VARCHAR primary keys?
...a decent programming background but my SQL experience is limited mostly to SELECT queries
– Rob
Jul 3 '12 at 14:47
...