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Overriding a Rails default_scope
...ed_at desc')
end
Foo.reorder('created_at asc')
runs the following SQL:
SELECT * FROM "foos" ORDER BY created_at asc
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Python: Select subset from list based on index set
...ecause this will be very familiar syntax to users of R, where this kind of selection is very powerful, especially when nested and/or multidimensional.
– Thomas Browne
May 25 '14 at 21:11
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What's the difference between NOT EXISTS vs. NOT IN vs. LEFT JOIN WHERE IS NULL?
... using Standard SQL.
An obvious omission is the equivalent using EXCEPT:
SELECT a FROM table1
EXCEPT
SELECT a FROM table2
Note in Oracle you need to use the MINUS operator (arguably a better name):
SELECT a FROM table1
MINUS
SELECT a FROM table2
Speaking of proprietary syntax, there may also ...
UITapGestureRecognizer breaks UITableView didSelectRowAtIndexPath
...ch.view isDescendantOfView:autocompleteTableView]) {
// Don't let selections of auto-complete entries fire the
// gesture recognizer
return NO;
}
return YES;
}
That took care of it. Hopefully this will help others as well.
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How to get the max of two values in MySQL?
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Use GREATEST()
E.g.:
SELECT GREATEST(2,1);
Note: Whenever if any single value contains null at that time this function always returns null (Thanks to user @sanghavi7)
s...
Copy Notepad++ text with formatting?
...
Here is an image from notepad++ when you select text to copy as html.
and how the formatted text looks like after pasting it in OneNote (similar to any other app that supports "Paste Special"):
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Use tab to indent in textarea
...which;
if (keyCode == 9) {
e.preventDefault();
var start = this.selectionStart;
var end = this.selectionEnd;
// set textarea value to: text before caret + tab + text after caret
$(this).val($(this).val().substring(0, start)
+ "\t"
+ $(this).val...
In SQL, what's the difference between count(column) and count(*)?
...a values(null,1)
insert #bla values(1,null)
insert #bla values(null,null)
select count(*),count(id),count(id2)
from #bla
results
7 3 2
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OSX - How to auto Close Terminal window after the “exit” command executed.
...
in Terminal.app
Preferences > Profiles > (Select a Profile) > Shell.
on 'When the shell exits' chosen 'Close the window'
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How to delete a row by reference in data.table?
...el.idxs' vs. 'keep.idxs'
keep.idxs <- setdiff(DT[, .I], del.idxs); # select row indexes to keep
cols = names(DT);
DT.subset <- data.table(DT[[1]][keep.idxs]); # this is the subsetted table
setnames(DT.subset, cols[1]);
for (col in cols[2:length(cols)]) {
DT.subset[, (col) := DT[...