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What does the [Flags] Enum Attribute mean in C#?
...ean, I prefer to have the full int in source code. If I have a column on a table in the database called MyEnum that stores a value of one of the enums, and a record has 131,072, I would need to get out my calculator to figure out that that corresponds to the enum with the value 1<<17. As oppos...
UnmodifiableMap (Java Collections) vs ImmutableMap (Google) [duplicate]
...odifiableMap.get("E"); // Will return "F".
In contrast to that, the ImmutableMap of Guava is really immutable: It is a true copy of a given map, and nobody may modify this ImmutableMap in any way.
Update:
As pointed out in a comment, an immutable map can also be created with the standard API ...
Difference between HashSet and HashMap?
... functions. This is critical because HashMap uses power-of two length hash tables." weblogs.java.net/blog/2005/06/18/hashmap-implementation - however, if you look at the doc you'll see that this hash distributes things over "buckets", so in the end I believe two things can get mapped the same bucket...
Nearest neighbors in high-dimensional data?
...set of points in a high-dimensional space into a set of bins, i.e., a hash table [1][3]. But unlike traditional hashes, a locality-sensitive hash places nearby points into the same bin.
LSH has some huge advantages. First, it is simple. You just compute the hash for all points in your database, the...
How to fix the Hibernate “object references an unsaved transient instance - save the transient insta
... I got this issue specifically when I used @Inheritance, in this case TABLE_PER_CLASS, I was referencing a subclass. CascadeType.ALL fixed it.
– Jim ReesPotter
Mar 17 '18 at 21:08
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How to implement a unique index on two columns in rails
I have a table and I'm trying to add a unique index on two columns. Those columns are also indexed. So my question is if I just can remove the indexes who were just for one column or if I have to use all three indexes:
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What is the difference between SQL, PL-SQL and T-SQL?
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Correction: SQL is a language to operate on tables for which SQL itself provides the definition. The SQL Standard avoids the words 'set' and 'relation' and their derivatives. SQL tables are not sets.
– onedaywhen
Nov 25 '11 at 12:...
In C++, is it still bad practice to return a vector from a function?
... as vectors/arrays—in many programming languages. Is this style now acceptable in C++0x if the class has a move constructor, or do C++ programmers consider it weird/ugly/abomination?
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How to run `rails generate scaffold` when the model already exists?
... does generate the view layer but it doesn't include the model attributes (table columns) and you have to add those by hand. Anybody know of a fix for this? I am on Rails 3.2.8.
– aaronbartell
Dec 3 '12 at 22:10
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Detect if stdin is a terminal or pipe?
...several methods to detect if a program is running interactively.
Following table shows an overview:
cmd\method ctermid open isatty fstat
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