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Objective-C: Reading a file line by line
...hen scan for newlines (or whatever other delimiter) and save any remaining characters for the next read, or read more characters if a newline hasn't been read yet. (NSFileHandle lets you read an NSData which you can then convert to an NSString, but it's essentially the same process.)
Apple has a St...
How do you use script variables in psql?
...t myvariable value
... and can then be substituted, for example, as ...
SELECT * FROM :myvariable.table1;
... or ...
SELECT * FROM table1 WHERE :myvariable IS NULL;
edit: As of psql 9.1, variables can be expanded in quotes as in:
\set myvariable value
SELECT * FROM table1 WHERE column1 ...
How to change options of with jQuery?
Suppose a list of options is available, how do you update the <select> with new <option> s?
9 Answers
...
How to check in Javascript if one element is contained within another
...arentNode)&&c!==p);
return !!c;
}
..or as one-liner (just 64 chars!):
function childOf(c,p){while((c=c.parentNode)&&c!==p);return !!c}
and jsfiddle here.
Usage:
childOf(child, parent) returns boolean true|false.
Explanation:
while evaluates as long as the while-condition...
jQuery or CSS selector to select all IDs that start with some string [duplicate]
How can I select all elements whose id starts with "player_"?
4 Answers
4
...
How can I check whether a radio button is selected with JavaScript?
...when one of the fields is null. How can I check whether a radio button is selected?
28 Answers
...
The SQL OVER() clause - when and why is it useful?
...ated values and then join it back to the original rowset, i.e. like this:
SELECT
orig.[Partition],
orig.Value,
orig.Value * 100.0 / agg.TotalValue AS ValuePercent
FROM OriginalRowset orig
INNER JOIN (
SELECT
[Partition],
SUM(Value) AS TotalValue
FROM OriginalRowset
G...
Select n random rows from SQL Server table
I've got a SQL Server table with about 50,000 rows in it. I want to select about 5,000 of those rows at random. I've thought of a complicated way, creating a temp table with a "random number" column, copying my table into that, looping through the temp table and updating each row with RAND() , and ...
PostgreSQL function for last inserted ID
...e:
INSERT INTO persons (lastname,firstname) VALUES ('Smith', 'John');
SELECT currval('persons_id_seq');
The name of the sequence must be known, it's really arbitrary; in this example we assume that the table persons has an id column created with the SERIAL pseudo-type. To avoid relying on thi...
Trigger change event of dropdown
...wns, the best way to do it is to have a script that returns the a prebuilt select box and an AJAX call that requests it.
Here is the documentation for jQuery's Ajax method if you need it.
$(document).ready(function(){
$('#countrylist').change(function(e){
$this = $(e.target);
...