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Select Multiple Fields from List in Linq
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Anonymous types allow you to select arbitrary fields into data structures that are strongly typed later on in your code:
var cats = listObject
.Select(i => new { i.category_id, i.category_name })
.Distinct()
.OrderByDescending(i => i.c...
Fastest way to determine if record exists
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SELECT TOP 1 products.id FROM products WHERE products.id = ?; will outperform all of your suggestions as it will terminate execution after it finds the first record.
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How can I select the first day of a month in SQL?
I just need to select the first day of the month of a given datetime variable.
30 Answers
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MySQL: Set user variable from result of query
...need to move the variable assignment into the query:
SET @user := 123456;
SELECT @group := `group` FROM user WHERE user = @user;
SELECT * FROM user WHERE `group` = @group;
Test case:
CREATE TABLE user (`user` int, `group` int);
INSERT INTO user VALUES (123456, 5);
INSERT INTO user VALUES (111111...
How do I bind to list of checkbox values with AngularJS?
...repeat="fruitName in fruits">
<input
type="checkbox"
name="selectedFruits[]"
value="{{fruitName}}"
ng-checked="selection.indexOf(fruitName) > -1"
ng-click="toggleSelection(fruitName)"
> {{fruitName}}
</label>
And the appropriate controller code would be:
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Should MySQL have its timezone set to UTC?
...the timezone will not change the stored datetime or
timestamp, but it will select a different datetime from
timestamp columns
Warning! UTC has leap seconds, these look like '2012-06-30 23:59:60' and can
be added randomly, with 6 months prior notice, due to the slowing of
the earths rotation
GMT con...
MySQL INNER JOIN select only one row from second table
...have multiple associated payments in the payments table. I would like to select all users who have payments, but only select their latest payment. I'm trying this SQL but i've never tried nested SQL statements before so I want to know what i'm doing wrong. Appreciate the help
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JOIN two SELECT statement results
Is it possible to join the results of 2 sql SELECT statements in one statement?
I have a database of tasks where each record is a separate task, with deadlines (and a PALT , which is just an INT of days from start to deadline. Age is also an INT number of days.)
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How do I check to see if a value is an integer in MySQL?
...e REGEXP operator, matching the string to a regular expression. Simply do
select field from table where field REGEXP '^-?[0-9]+$';
this is reasonably fast. If your field is numeric, just test for
ceil(field) = field
instead.
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jQuery get value of selected radio button
The problem statement is simple. I need to see if user has selected a radio button from a radio group. Every radio button in the group share same id.
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