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SQL Server - Create a copy of a database table and place it in the same database?
...is will create a new table ABC_1 that has the same column structure as ABC and contains the same data. Constraints (e.g. keys, default values), however, are -not- copied.
You can run this query multiple times with a different table name each time.
If you don't need to copy the data, only to cre...
How to validate an email address in PHP
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The easiest and safest way to check whether an email address is well-formed is to use the filter_var() function:
if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {
// invalid emailaddress
}
Additionally you can check whether the do...
Visual Studio 2013 doesn't discover unit tests
...isual studio 2013 that is composed by one web project, one library project and one unit test project. When I open the solution and try to run the unit tests they are not discover by visual studio. To run the tests I try to go to the menu and choose Test -> Run -> Run all tests or by opening the test...
Free XML Formatting tool [closed]
...free XML formatting (indent) tool available where I can past an XML string and have it formatted so I can read the XML document correctly?
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What's the -practical- difference between a Bare and non-Bare repository?
I've been reading about the bare and non-bare / default repositores in Git. I haven't been able to understand quite well (theoretically) about the differences between them, and why I should "push" to a bare repository. Here's the deal:
...
Understanding offsetWidth, clientWidth, scrollWidth and -Height, respectively
... on StackOverflow regarding offsetWidth / clientWidth / scrollWidth (and -Height , respectively), but none give comprehensive explanation of what those values are.
...
How to speed up insertion performance in PostgreSQL
...n the PostgreSQL manual, depesz's excellent-as-usual article on the topic, and this SO question.
(Note that this answer is about bulk-loading data into an existing DB or to create a new one. If you're interested DB restore performance with pg_restore or psql execution of pg_dump output, much of thi...
How to map and remove nil values in Ruby
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Ruby 2.7 is introducing filter_map for this exact purpose. It's idiomatic and performant, and I'd expect it to become the norm very soon.
For example:
numbers = [1, 2, 5, 8, 10, 13]
enum.filter_map { |i| i * 2 if i.even? }
# => [4, 16, 20]
In your case, as the block evaluates to falsey, simp...
Any way to select without causing locking in MySQL?
...rver you would do the following:
SELECT * FROM TABLE_NAME WITH (nolock)
and the MYSQL equivalent is
SET SESSION TRANSACTION ISOLATION LEVEL READ UNCOMMITTED ;
SELECT * FROM TABLE_NAME ;
SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ ;
EDIT
Michael Mior suggested the following (from t...
Are duplicate keys allowed in the definition of binary search trees?
I'm trying to find the definition of a binary search tree and I keep finding different definitions everywhere.
12 Answers
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