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Order a MySQL table by two columns
...h query not working in my case.. Tn this case, I dont get sorting for City select distinct City, Country from customers order by Country desc, City desc;
– Pra_A
Sep 15 '16 at 6:55
...
Why Android Studio says “Waiting For Debugger” if am NOT debugging?
...e. Just go to "Android device"->"Settings"->"Developer Options"->"Select app to be debugged". It will likely be pointing to your application. Just select the option and then select "None".
Note: As mentioned, even if "None" is already selected, re-selecting "None" appears to correct the pr...
How does the SQL injection from the “Bobby Tables” XKCD comic work?
..., the parenthesis makes more sense with an INSERT. Thinking backwards, the SELECT would not run anyway as the Insert of the Little Bobby Tables in the table would have already dropped the table.
– ypercubeᵀᴹ
Jan 21 '13 at 21:41
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How can I get enum possible values in a MySQL database?
... This solution works on codeigniter github.com/thiswolf/codeigniter-enum-select-boxes
– You Know Nothing Jon Snow
Jul 7 '13 at 16:28
3
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How do MySQL indexes work?
...be faster to go through the pages one by one (in a database, this is "poor selectivity").
For a 10-page book, it makes no sense to make an index, as you may end up with a 10-page book prefixed by a 5-page index, which is just silly - just scan the 10 pages and be done with it.
The index also needs t...
Replacement for “rename” in dplyr
...
The next version of dplyr will support an improved version of select that also incorporates renaming:
> mtcars2 <- select( mtcars, disp2 = disp )
> head( mtcars2 )
disp2
Mazda RX4 160
Mazda RX4 Wag 160
Datsun 710 108
Hornet 4 Drive 258
H...
IntelliJ IDEA way of editing multiple lines
...ossibility to edit multiple lines.
Use:
Alt + Shift + Mouse click
for selection. More about this new improvement in IntelliJ blogpost here. Very useful feature.
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MySQL date format DD/MM/YYYY select query?
...ably just want to format the output date? then this is what you are after
SELECT *, DATE_FORMAT(date,'%d/%m/%Y') AS niceDate
FROM table
ORDER BY date DESC
LIMIT 0,14
Or do you actually want to sort by Day before Month before Year?
...
How to add column if not exists on PostgreSQL?
...s, _col text, _type regtype)
RETURNS bool AS
$func$
BEGIN
IF EXISTS (SELECT 1 FROM pg_attribute
WHERE attrelid = _tbl
AND attname = _col
AND NOT attisdropped) THEN
RETURN FALSE;
ELSE
EXECUTE format('ALTER TABLE %s ADD COLUMN %I %s...
Converting a generic list to a CSV string
...s for us.
List<int> myValues;
string csv = String.Join(",", myValues.Select(x => x.ToString()).ToArray());
For the general case:
IEnumerable<T> myList;
string csv = String.Join(",", myList.Select(x => x.ToString()).ToArray());
As you can see, it's effectively no different. Beware...