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Which characters make a URL invalid?
Which characters make a URL invalid?
10 Answers
10
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How to use PrimeFaces p:fileUpload? Listener method is never invoked or UploadedFile is null / throw
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Looks like javax.faces.SEPARATOR_CHAR must not be equal to _
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GROUP_CONCAT ORDER BY
...
You can use ORDER BY inside the GROUP_CONCAT function in this way:
SELECT li.client_id, group_concat(li.percentage ORDER BY li.views ASC) AS views,
group_concat(li.percentage ORDER BY li.percentage ASC)
FROM li GROUP BY client_id
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Database development mistakes made by application developers [closed]
... the log output from Hibernate and you'll see all the queries begin with:
SELECT DISTINCT ...
This is a bit of a shortcut to ensuring you don't return duplicate rows and thus get duplicate objects. You'll sometimes see people doing this as well. If you see it too much it's a real red flag. Not...
How do I drop a foreign key constraint only if it exists in sql server?
...target a foreign key constraint on a specific table, use this:
IF EXISTS (SELECT *
FROM sys.foreign_keys
WHERE object_id = OBJECT_ID(N'dbo.FK_TableName_TableName2')
AND parent_object_id = OBJECT_ID(N'dbo.TableName')
)
ALTER TABLE [dbo.TableName] DROP CONSTRAINT [FK_TableName_TableName2]...
How to paste yanked text into the Vim command line
...nto your buffer.
Let's decompose: " is a Normal mode command that lets you select what register is to be used during the next yank, delete or paste operation. So ": selects the colon register (storing last command). Then p is a command you already know, it pastes the contents of the register.
cf. :...
How can I toggle word wrap in Visual Studio?
... Visual Studio behaves differently to other editors:
Triple click doesn't select whole line
Cut command doesn't delete whole line
Pressing End key twice does not move cursor to end of line
Unfortunately these bugs have been closed "lower priority".
If you'd like these bugs fixed, please vote for ...
sql “LIKE” equivalent in django query
... = table.objects.filter(string__contains='pattern')
The SQL equivalent is
SELECT ... WHERE string LIKE '%pattern%';
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When should I use a table variable vs temporary table in sql server?
... source for the data inserted to the table is from a potentially expensive SELECT statement then consider that using a table variable will block the possibility of this using a parallel plan.
If you need the data in the table to survive a rollback of an outer user transaction then use a table variab...
COALESCE Function in TSQL
...ks perfectly & gives a good visual explanation of how COALESCE works:
SELECT Name, Class, Color, ProductNumber,
COALESCE(Class, Color, ProductNumber) AS FirstNotNull
FROM Production.Product
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