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Unable to create a constant value of type Only primitive types or enumeration types are supported in
...I'm concerned about performance I should avoid doing this as it would load all data in memory first and then query it. Should I write raw sql for this scenarios?
– Arvand
Dec 28 '15 at 11:30
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What's the difference between IComparable & IEquatable interfaces?
...eckles or their weight. Hence, we would implement different IComparers for all these cases.
– Konrad Rudolph
Mar 9 '10 at 19:08
2
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Simple way to copy or clone a DataRow?
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Apparently Clone() only provides a shallow copy. Do you think that will be enough to create an identical copy or is a deep clone required?
– Paul Matthews
Aug 19 '12 at 11:08
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Erasing elements from a vector
...y once in the vector. It may be present multiple times and I need to clear all of them. My code is something like this:
5 A...
Cannot change column used in a foreign key constraint
...eign key field and reference must be equal.
This means your foreign key disallows changing the type of your field.
One solution would be this:
LOCK TABLES
favorite_food WRITE,
person WRITE;
ALTER TABLE favorite_food
DROP FOREIGN KEY fk_fav_food_person_id,
MODIFY person_id SMALLIN...
How to send a JSON object using html form data
...l form data then you have to decode it using json_decode. You'll then get all data in an array.
$.ajax({
type: "POST",
url: "serverUrl",
data: formData,
success: function(){},
dataType: "json",
contentType : "application/json"
});
...
Grouped LIMIT in PostgreSQL: show the first N rows for each group?
... For those who works with like millions rows and seeks for really performant way to do this - poshest's answer is the way to go. Just dont forget to spice ti up with proper indexing.
– Diligent Key Presser
Jun 20 '19 at 8:46
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Show an image preview before upload
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HTML5 comes with File API spec, which allows you to create applications that let the user interact with files locally; That means you can load files and render them in the browser without actually having to upload the files. Part of the File API is the FileReader...
Can you resolve an angularjs promise before you return it?
...Nizet's Plunkr but refactored to work within the context of what was originally asked (i.e. a function call to service) and actually on site.
Inside the service...
function getSomething(id) {
// There will always be a promise so always declare it.
var deferred = $q.defer();
if (Cache[i...
Is 'float a = 3.0;' a correct statement?
...terals notation in specific scenarios.
For performance reasons:
Specifically, consider:
float foo(float x) { return x * 0.42; }
Here the compiler will emit a conversion (that you will pay at runtime) for each returned value. To avoid it you should declare:
float foo(float x) { return x * 0.42...