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What is this 'Lambda' everyone keeps speaking of?
... without bloating your code unnecessarily. For example, in Ruby:
(1..100).select {|num| num % 2 == 0}
This will create an array containing the even numbers between 1 and 100. We don't have to write out an explicit loop — the select method takes a function that it uses to test the values, so all...
Apply CSS styles to an element depending on its child elements
...but this isn't possible.
You may want to consider looking at jQuery. Its selectors work very well with 'containing' types. You can select the div, based on its child contents and then apply a CSS class to the parent all in one line.
If you use jQuery, something along the lines of this would may w...
SQL, Postgres OIDs, What are they and why are they useful?
...ned system column oid will no longer be invisible by default. Performing a SELECT * will now include this column. Note that this extra “surprise” column may break naïvely written SQL code.
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Get the first item from an iterable that matches a condition
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Since this is the selected answer, I feel compelled to share an answer to selecting the first element correctly here. In short: usage of next shouldn't be encouraged.
– guyarad
Jul 7 '16 at 10:56
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Case insensitive string compare in LINQ-to-SQL
...ple this LINQ query:
from user in Users
where user.Email == "foo@bar.com"
select user
gets translated to the following SQL by the LINQ-to-SQL provider:
SELECT [t0].[Email]
FROM [User] AS [t0]
WHERE [t0].[Email] = @p0
-- note that "@p0" is defined as nvarchar(11)
-- and is passed my value of "foo...
How do you log all events fired by an element in jQuery?
...ouse'); // logs mouse events on the body
monitorEvents(document.body.querySelectorAll('input')); // logs all events on inputs
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How to display unique records from a has_many through relationship?
...r the SQL DISTINCT stmt (e.g. has_many :products, :through => :orders, :select => "DISTINCT products.*). In the first case, ALL records are fetched and rails removes the duplicates for you. In the later case, only non-duplicate records are fetched from the db so it might offer better performan...
Two submit buttons in one form
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For i18n purposes it might be better to use the selected answer.
– Robin Green
Nov 29 '12 at 16:08
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Submitting HTML form using Jquery AJAX
...ral web actions GET, POST, PUT, and DELETE; these directly correspond with SELECT/Retreiving DATA, INSERTING DATA, UPDATING/UPSERTING DATA, and DELETING DATA. A default HTML/ASP.Net webform/PHP/Python or any other form action is to "submit" which is a POST action. Because of this the below will al...
How to implement one-to-one, one-to-many and many-to-many relationships while designing tables?
...ction table
Example queries:
-- Getting all students for a class:
SELECT s.student_id, last_name
FROM student_classes sc
INNER JOIN students s ON s.student_id = sc.student_id
WHERE sc.class_id = X
-- Getting all classes for a student:
SELECT c.class_id, name
FROM s...