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MySQL select where column is not empty
In MySQL, can I select columns only where something exists?
13 Answers
13
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What is Ad Hoc Query?
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Ad hoc is latin for "for this purpose". You might call it an "on the fly" query, or a "just so" query. It's the kind of SQL query you just loosely type out where you need it
var newSqlQuery = "SELECT * FROM table WHERE id = " + myI...
CSS – why doesn’t percentage height work? [duplicate]
... defaults to the height of the block's content. So, given something like this:
<div id="outer">
<div id="inner">
<p>Where is pancakes house?</p>
</div>
</div>
#inner will grow to be tall enough to contain the paragraph and #outer will grow to be...
Maximum packet size for a TCP connection
What is the maximum packet size for a TCP connection or how can I get the maximum packet size?
10 Answers
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What are the differences between Perl, Python, AWK and sed? [closed]
... of appearance, the languages are sed, awk, perl, python.
The sed program is a stream editor and is designed to apply the actions from a script to each line (or, more generally, to specified ranges of lines) of the input file or files. Its language is based on ed, the Unix editor, and although it h...
What is the difference between Type and Class?
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The following answer is from Gof book (Design Patterns)
An object's class defines how the
object is implemented .The class
defines object's internal state and
the implementation of its
operations.
In contrast, an object's
type ...
What does f+++++++++ mean in rsync logs?
...better understand the cryptic result lines:
1 - A huge advantage of rsync is that after an interruption the next time it continues smoothly.
The next rsync invocation will not transfer the files again, that it had already transferred, if they were not changed in the meantime. But it will start che...
What Makes a Method Thread-safe? What are the rules?
...here are probably a million one-off situations, but what about in general? Is it this simple?
4 Answers
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What exactly is an Assembly in C# or .NET?
Could you please explain what is an Assembly in C# or .NET?
9 Answers
9
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What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
The "N+1 selects problem" is generally stated as a problem in Object-Relational mapping (ORM) discussions, and I understand that it has something to do with having to make a lot of database queries for something that seems simple in the object world.
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