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SQL left join vs multiple tables on FROM line?
...oin criteria, is being deprecated in most modern databases.
It's not just for show, the old syntax has the possibility of being ambiguous when you use both INNER and OUTER joins in the same query.
Let me give you an example.
Let's suppose you have 3 tables in your system:
Company
Department
Empl...
How can I remove a button or make it invisible in Android?
...button will be completely "removed" -- the buttons space will be available for another widgets) or INVISIBLE (button will became "transparent" -- its space will not be available for another widgets):
View b = findViewById(R.id.button);
b.setVisibility(View.GONE);
or in xml:
<Button ... androi...
How to persist a property of type List in JPA?
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Sorry to revive an old thread but should anyone be looking for an alternative solution where you store your string lists as one field in your database, here's how I solved that. Create a Converter like this:
import java.util.Arrays;
import java.util.List;
import javax.persistence.A...
CSS – why doesn’t percentage height work? [duplicate]
How come a percentage value for height doesn’t work but a percentage value for width does?
6 Answers
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Is a one column table good design? [closed]
...st cases of single column design could benefit from an additional column. For example, State Codes can typically have the Full State name spelled out in a second column. Or a blacklist can have notes associated. But, if your design really does not need that information, then it's perfectly ok to ...
SQL Update with row_number()
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you can massively improve future update performance with a WHERE clause (see my answer based on this)
– Simon_Weaver
Dec 28 '16 at 7:46
add a c...
How do you do a limit query in JPQL or HQL?
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This was posted on the Hibernate forum a few years back when asked about why this worked in Hibernate 2 but not in Hibernate 3:
Limit was never a supported clause
in HQL. You are meant to use
setMaxResults().
So if it worked in Hibernate 2, it seem...
When to use .First and when to use .FirstOrDefault with LINQ?
...heck whether there was an element or not. In other words, when it is legal for the sequence to be empty. You should not rely on exception handling for the check. (It is bad practice and might hurt performance).
Finally, the difference between First() and Take(1) is that First() returns the element ...
Rails select helper - Default selected value, how?
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without params, options_for_select is better way. It is good for any situation, good for form edit too.
– Adriano Resende
Jun 25 '15 at 13:07
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How to become an OpenCart guru? [closed]
...ms like they have no documentation except some api calls on their official forums. I have experience with Zend framework and CodeIgniter framework. Can any OpenCart masters recommend me the best way to learn it and master in shortest amount of time? I have to do a big project with it soon.
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