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What do people find difficult about C pointers? [closed]
... left till someone tries to build a compiler.
"Memory is memory is memory" Casting just changes which versions of operators or how much room the compiler gives for a particular chunk of memory. You know you're dealing with this problem when people talk about "what (primitive) variable X really is".
...
How do I check how many options there are in a dropdown menu?
...
var length = $('#mySelectList').children('option').length;
or
var length = $('#mySelectList > option').length;
This assumes your <select> list has an ID of mySelectList.
http://api.jquery.com/length/
http://api.jquery.com/childr...
How do I add options to a DropDownList using jQuery?
...lugins,
var myOptions = {
val1 : 'text1',
val2 : 'text2'
};
var mySelect = $('#mySelect');
$.each(myOptions, function(val, text) {
mySelect.append(
$('<option></option>').val(val).html(text)
);
});
If you had lots of options, or this code needed to be run very ...
Select statement to find duplicates on certain fields
...get the list of fields for which there are multiple records, you can use..
select field1,field2,field3, count(*)
from table_name
group by field1,field2,field3
having count(*) > 1
Check this link for more information on how to delete the rows.
http://support.microsoft.com/kb/139444
There sh...
must appear in the GROUP BY clause or be used in an aggregate function
...
Yes, this is a common aggregation problem. Before SQL3 (1999), the selected fields must appear in the GROUP BY clause[*].
To workaround this issue, you must calculate the aggregate in a sub-query and then join it with itself to get the additional columns you'd need to show:
SELECT m.cname...
MySQL ON vs USING?
...n tables ON a column, a set of columns and even a condition. For example:
SELECT * FROM world.City JOIN world.Country ON (City.CountryCode = Country.Code) WHERE ...
USING is useful when both tables share a column of the exact same name on which they join. In this case, one may say:
SELECT ... FR...
How to submit form on change of dropdown list?
I am creating a page in JSP where I have a dropdown list and once the user selects a value he has to click on the go button and then the value is sent to the Servlet.
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How can I select rows with most recent timestamp for each key value?
...r data. Each row has a sensor id, a timestamp, and other fields. I want to select a single row with latest timestamp for each sensor, including some of the other fields.
...
How to convert List to List?
...
listofIDs.Select(int.Parse).ToList()
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C/C++ with GCC: Statically add resource files to executable/library
...t uniform, then char is probably the most convenient: take its address and cast the pointer to the proper type as you traverse the data.
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