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Are there disadvantages to using a generic varchar(255) for all text-based fields?
...se Ruby on Rails migrations map String fields to VARCHAR(255) by default and I never bothered to override it).
7 Answer...
What does java:comp/env/ do?
...epartments. For example, future
policies might allow you to name users
and organizations/departments by using
names such as "java:user/alice" and
"java:org/engineering".
In the "comp" context, there are two
bindings: "env" and "UserTransaction".
The name "env" is bound to a subtree
...
How to draw a path on a map using kml file?
Can I parse kml file in order to display paths or points in Android? Please could you help me with that?
4 Answers
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Only get hash value using md5sum (without filename)
...ng output on Mac MD5 (/Users/hello.txt) = 24811012be8faa36c8f487bbaaadeb71 and your code returns MD5.
– alper
Aug 3 '18 at 21:06
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What's the difference between IQueryable and IEnumerable
...ry IEnumerables using the Linq extensions. So what is this IQueryable and how does it differ?
7 Answers
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Creating Unicode character from its number
...
That's why I said 'below'! And I need to emphasise that, despite the fact that Java chars only go up to 0xffff, Unicode code points go up to 0xfffff. The Unicode standard got changed after Java was designed. These days Java chars technically hold UTF-1...
Difference between & and && in Java? [duplicate]
I was just wondering what the difference between & and && is?
A few days I wrote a condition for an if statement the looked something like:
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Why is a “GRANT USAGE” created the first time I grant a user privileges?
I'm new to the admin side of DBMS and was setting up a new database tonight (using MySQL) when I noticed this. After granting a user a privilege for the first time, another grant is created that looks like
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How to truncate string using SQL server
... Fiddle with Demo.
This will return the first 15 characters of the string and then concatenates the ... to the end of it.
If you want to to make sure than strings less than 15 do not get the ... then you can use:
select
case
when len(col)>=15
then left(col, 15) + '...'
else co...
How do I push amended commit to the remote Git repository?
When I've worked a bit with my source code, I did my usual thing commit and then I pushed to a remote repository. But then I noticed I forgot to organize my imports in the source code. So I do the amend command to replace the previous commit:
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