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Is there any difference between “!=” and “” in Oracle Sql?
... first-class type in SQL (which is different from PL/SQL). I. e. you can't SELECT 1 = 1 FROM dual like in some other systems. So booleans have their own set of operators valid only in logical contexts (WHERE or HAVING or similar clauses). NOT is the only boolean negation operator in Oracle's SQL (AF...
How does HTTP file upload work?
...
Let's take a look at what happens when you select a file and submit your form (I've truncated the headers for brevity):
POST /upload?upload_progress_id=12344 HTTP/1.1
Host: localhost:3000
Content-Length: 1325
Origin: http://localhost:3000
... other headers ...
Conten...
CodeIgniter activerecord, retrieve last insert id?
...ed like this. may be wrong. but working well for me
$this->db->select_max('{primary key}');
$result= $this->db->get('{table}')->row_array();
echo $result['{primary key}'];
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MySQL - length() vs char_length()
... in two bytes. Or UTF-8, where the number of bytes varies. For example:
select length(_utf8 '€'), char_length(_utf8 '€')
--> 3, 1
As you can see the Euro sign occupies 3 bytes (it's encoded as 0xE282AC in UTF-8) even though it's only one character.
...
Git Symlinks in Windows
... which finds all of the symlinks throughout the repository, as before) for selectively transforming git symlinks into NTFS hardlinks+junctions.
The checkout-symlinks alias has also been updated to accept multiple arguments (or none at all, == everything) for selective reversal of the aforementioned ...
How do I make a list of data frames?
...e of your choice.
GETDF_FROMLIST <- function(DF_LIST, ITEM_LOC){
DF_SELECTED <- DF_LIST[[ITEM_LOC]]
return(DF_SELECTED)
}
Now get the one you want.
D1 <- GETDF_FROMLIST(mylist, 1)
D2 <- GETDF_FROMLIST(mylist, 2)
D3 <- GETDF_FROMLIST(mylist, 3)
D4 <- GETDF_FROMLIST(mylist,...
How to disable the warning 'define' is not defined using JSHint and RequireJS
...ty Tools > JSHint
Scroll down to "Environments" and make sure you have selected the checkbox to enable "Mocha" which will set up the definitions for JSHint for Mocha for you.
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How to dismiss ViewController in Swift?
...with "Done" as Identifier
invoke the Assistant Editor with the Done button selected
create an IBAction for this button
add this line into the brackets:
self.dismissViewControllerAnimated(true, completion: nil)
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How to find out client ID of component for ajax update/render? Cannot find component with expression
... <ui:repeat>.
When using PrimeFaces, consider Search Expressions or Selectors
PrimeFaces Search Expressions allows you to reference components via JSF component tree search expressions. JSF has several builtin:
@this: current component
@form: parent UIForm
@all: entire document
@none: noth...
Understanding the Event Loop
... of queues of stuff that needs doing and every "tick" of the event loop it selects one, removes it from the queue, and runs it.
A key thing to understand is that node relies on the OS for most of the heavy lifting. So incoming network requests are actually tracked by the OS itself and when node is ...