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How to get number of rows using SqlDataReader in C#
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There are only two options:
Find out by reading all rows (and then you might as well store them)
run a specialized SELECT COUNT(*) query beforehand.
Going twice through the DataReader loop is really expensive, you would have to re-execute the query.
And (thanks to Pete ...
The JPA hashCode() / equals() dilemma
...als() implementation should be used for JPA entity classes. Most (if not all) of them depend on Hibernate, but I'd like to discuss them JPA-implementation-neutrally (I am using EclipseLink, by the way).
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CSS: 100% font size - 100% of what?
...he percent-value is supposed to be. I understand this is 'the same size in all browsers'. I also read this, for instance:
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What is the shortcut to Auto import all in Android Studio?
... and make the following changes:
change Insert imports on paste value to All
markAdd unambigious imports on the fly option as checked
On a Mac, do the same thing in Android Studio -> Preferences
After this, all unambiguous imports will be added automatically.
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Can multiple different HTML elements have the same ID if they're different elements?
...ntirely possible to have multiple elements with the same ID. It's not generally best practice, but it does have its occasional uses. Everyone seems to cite how would selectors work, well if your going in knowing you'll have conflicting IDs, you use your selectors with a parent, where the IDs under t...
What is the difference between getFields and getDeclaredFields in Java reflection
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getFields()
All the public fields up the entire class hierarchy.
getDeclaredFields()
All the fields, regardless of their accessibility but only for the current class, not any base classes that the current class might be inheriting from...
java.lang.NoClassDefFoundError: org/hamcrest/SelfDescribing
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Add hamcrest-all-X.X.jar to your classpath.
Latest version as of Feb 2015 is 1.3:
http://code.google.com/p/hamcrest/downloads/detail?name=hamcrest-all-1.3.jar&can=2&q=
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What does “Memory allocated at compile time” really mean?
... languages like C and C++, people often refer to static and dynamic memory allocation. I understand the concept but the phrase "All memory was allocated (reserved) during compile time" always confuses me.
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Get names of all files from a folder with Ruby
I want to get all file names from a folder using Ruby.
19 Answers
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How do you fix a bad merge, and replay your good commits onto a fixed merge?
I accidentally committed an unwanted file ( filename.orig while resolving a merge) to my repository several commits ago, without me noticing it until now. I want to completely delete the file from the repository history.
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