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Best way to check if object exists in Entity Framework?
...t.Employees.Any()) Then ' Check if there are "any" records in the Employee table
Dim employee = From c In context.Employees Select c.PayrollNumber ' Select just the PayrollNumber column to work with
For Each item As Object In employee ' Loop through each employee in the Employees ent...
SQL: How to properly check if a record exists
...
It's better to use either of the following:
-- Method 1.
SELECT 1
FROM table_name
WHERE unique_key = value;
-- Method 2.
SELECT COUNT(1)
FROM table_name
WHERE unique_key = value;
The first alternative should give you no result or one result, the second count should be zero or one.
How old is...
UITextField text change event
...ange method you can examine the contents of the textField, and reload your table view as needed.
You could use that and put calculateAndUpdateTextFields as your selector.
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Virtual functions and performance - C++
...ual is a per-function attribute. A function only needs to be defined via vtable if it's marked as virtual or if it's overriding a base class that has it as virtual. You'll often see classes that have a group of virtual functions for public interface, and then a lot of inline accessors and so on. (...
Can CSS force a line break after each word in an element?
...content;
width: -moz-min-content;
width: min-content;
display: table-caption;
display: -ms-grid;
-ms-grid-columns: min-content;
}
where <parent-width> is the width of the parent element (or an arbitrary high value that doesn't fit into one line). That way you can be sure ...
DataTable: Hide the Show Entries dropdown but keep the Search box
... possible to hide the Show Entries dropdown but keep the Search box in DataTable? I want to always display 10 rows with pagination at the bottom along with search box but do not want to display the Show entries dropdown.
...
EF LINQ include multiple and nested entities
...n, that tells Entity Framework that you want it to include data from other tables.
The Include syntax can also be in string. Like this:
db.Courses
.Include("Module.Chapter")
.Include("Lab")
.Single(x => x.Id == id);
But the samples in LinqPad exp...
How to make join queries using Sequelize on Node.js
...sted, but what it does is basically just aliasing all columns of the users table to make sure they are placed into the correct model when returned and not mixed up with the posts model
Other than that you'll notice that it does a JOIN instead of selecting from two tables, but the result should be t...
What are bitwise operators?
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It is worth noting that the single-bit truth tables listed as other answers work on only one or two input bits at a time. What happens when you use integers, such as:
int x = 5 & 6;
The answer lies in the binary expansion of each input:
5 = 0 0 0 0 0 1 0 1
&am...
How do I wrap text in a pre tag?
... of the line). developer.mozilla.org/en-US/docs/Web/CSS/white-space has a table summarizing the behavior of white-space values.
– Paul
Jan 26 '17 at 14:57
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