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COUNT(*) vs. COUNT(1) vs. COUNT(pk): which is better? [duplicate]
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Bottom Line
Use either COUNT(field) or COUNT(*), and stick with it consistently, and if your database allows COUNT(tableHere) or COUNT(tableHere.*), use that.
In short, don't use COUNT(1) for anything. It's a one-trick po...
Task vs Thread differences [duplicate]
I'm new to parallel programming. There are two classes available in .NET: Task and Thread .
4 Answers
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How do DATETIME values work in SQLite?
...ve a storage class set aside for storing dates and/or times" and it's "capable of storing dates and times as TEXT, REAL, or INTEGER values".
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Python logging not outputting anything
...ll ignore any logging with a level that is lower than warning, including debug loggings.
This is explained in the tutorial:
import logging
logging.warning('Watch out!') # will print a message to the console
logging.info('I told you so') # will not print anything
The 'info' line doesn't print any...
Find MongoDB records where array field is not empty
...n use:
ME.find({ pictures: { $exists: true, $not: {$size: 0} } })
MongoDB don't use indexes if $size is involved, so here is a better solution:
ME.find({ pictures: { $exists: true, $ne: [] } })
Since MongoDB 2.6 release, you can compare with the operator $gt but could lead to unexpected result...
How to overlay one div over another div
...ative;
}
#navi,
#infoi {
width: 100%;
height: 100%;
position: absolute;
top: 0;
left: 0;
}
#infoi {
z-index: 10;
}
<div id="container">
<div id="navi">a</div>
<div id="infoi">
<img src="https://appharbor.com/assets/images/stackoverflow-l...
What is the difference between DAO and Repository patterns?
What is the difference between Data Access Objects (DAO) and Repository patterns? I am developing an application using Enterprise Java Beans (EJB3), Hibernate ORM as infrastructure, and Domain-Driven Design (DDD) and Test-Driven Development (TDD) as design techniques.
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Why is using the rails default_scope often recommend against?
...n the internet people mention that using the rails default_scope is a bad idea, and the top hits for default_scope on stackoverflow are about how to overwrite it. This feels messed up, and merits an explicit question (I think).
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What exactly is RESTful programming?
...tural style called REST (Representational State Transfer) advocates that web applications should use HTTP as it was originally envisioned. Lookups should use GET requests. PUT, POST, and DELETE requests should be used for mutation, creation, and deletion respectively.
REST proponents tend to favor ...
How do I reflect over the members of dynamic object?
I need to get a dictionary of properties and their values from an object declared with the dynamic keyword in .NET 4? It seems using reflection for this will not work.
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