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What is the difference between active and passive FTP?
...part of this, the server also returns to the client the port number it has selected to listen on, so that the client knows how to connect to it.
Once the client knows that, it can then successfully create the data channel and continue.
More details are available in the RFC: https://www.ietf.org/rf...
Expand a random range from 1–5 to 1–7
...t a non-zero. That's what this code is doing: the i and j indexes randomly select a location on the dart board, and if we don't get a good result, we keep throwing darts.
Like Adam said, this can run forever in the worst case, but statistically the worst case never happens. :)
...
Is it possible to get element from HashMap by its position?
... n ++;
}
return null;
}
The function can return the selected entry.
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How Can I Download a File from EC2 [closed]
...nager, click File ▸ Connect to Server.
Enter the server address, select the type of server, and enter any additional information as required. Then click Connect. Details on
server types are listed below.
For servers on the internet, you can usually use the domain name. For
computers ...
Dropping Unique constraint from MySQL table
...AINT unq_tab_id UNIQUE(id));
-- checking constraint name if autogenerated
SELECT * FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE TABLE_NAME = 'tab';
-- dropping constraint
ALTER TABLE tab DROP CONSTRAINT unq_tab_id;
db<>fiddle demo
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HTML text input allow only numeric input
...x, inputFilter) {
["input", "keydown", "keyup", "mousedown", "mouseup", "select", "contextmenu", "drop"].forEach(function(event) {
textbox.addEventListener(event, function() {
if (inputFilter(this.value)) {
this.oldValue = this.value;
this.oldSelectionStart = this.selecti...
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...
Is there a best practice for generating html with javascript
...$.template('<div><img src="${url}" />${name}</div>');
$(selector).append( t , {
url: jsonObj.url,
name: jsonObj.name
});
I say go the cool route (and better performing, more maintainable), and use templating.
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filter for complete cases in data.frame using dplyr (case-wise deletion)
...function which lets you specify columns (basically everything which dplyr::select can understand) which should not have any NA values (modeled after pandas df.dropna()):
drop_na <- function(data, ...){
if (missing(...)){
f = complete.cases(data)
} else {
f <- complete....
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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