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Pandas DataFrame column to list [duplicate]
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Easier way is just to do df['b'].values. If you select the column before using .values it will avoid a conversion and preserve the original dtype. This is also much more efficient.
– JohnE
Dec 7 '16 at 12:33
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Create PostgreSQL ROLE (user) if it doesn't exist
...r fashion to what you had in mind:
DO
$do$
BEGIN
IF NOT EXISTS (
SELECT FROM pg_catalog.pg_roles -- SELECT list can be empty for this
WHERE rolname = 'my_user') THEN
CREATE ROLE my_user LOGIN PASSWORD 'my_password';
END IF;
END
$do$;
(Building on @a_horse_with_no_name's...
What difference does .AsNoTracking() make?
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Can we get the same benefits for anonymous classes in select query, such as context.Users.Select(u=> new { Name = u.Name })? Thanks.
– Dilhan Jayathilake
Feb 6 '17 at 23:33
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Difference between View and table in sql
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A table contains data, a view is just a SELECT statement which has been saved in the database (more or less, depending on your database).
The advantage of a view is that it can join data from several tables thus creating a new view of it. Say you have a database w...
How should I edit an Entity Framework connection string?
...nnection strings. Now go to the edmx, right click on the designer surface, select Update model from database, choose the connection string from the dropdown, Click next, Add or Refresh (select what you want) and finish.
In the output window it will show something like this,
Generated model file: U...
Proper Linq where clauses
...cate are combined and only one iterator is involed. Look atEnumerable.WhereSelectEnumerableIterator.
– Cybermaxs
Apr 4 '13 at 12:46
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View more than one project/solution in Visual Studio
... With multiple projects, if I have multiple main() methods, how do I select which I want to have compiled?
– 5Daydreams
Aug 11 at 16:12
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Getting output of system() calls in Ruby
...ble like so:
output = `ls`
p output
or
printf output # escapes newline chars
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How does Facebook Sharer select Images and other metadata when sharing my URL?
...s pulled from the source as a preview for their link. How are these images selected, and how can I ensure that any particular image on my page is always included in this list?
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How do I generate a constructor from class fields using Visual Studio (and/or ReSharper)?
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ReSharper offers a Generate Constructor tool where you can select any field/properties that you want initialized. I use the Alt + Ins hot-key to access this.
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