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Heroku Postgres - terminate hung query (idle in transaction)
...'s not desirable or not an option ...)
Find the PID by running this sql:
SELECT pid , query, * from pg_stat_activity
WHERE state != 'idle' ORDER BY xact_start;
(The query may need mending dependent of the version of postgres - eventually, just select * from pg_stat_activity). You'll find the ...
What is the difference between '>' and a space in CSS selectors?
...
A > B will only select B that are direct children to A (that is, there are no other elements inbetween).
A B will select any B that are inside A, even if there are other elements between them.
...
Faster way to develop and test print stylesheets (avoid print preview every time)?
...P (Mac) or Ctrl+Shift+P (Windows, Linux))
2. Start typing Rendering and select Show Rendering.
3. For the Emulate CSS Media dropdown, select print.
UPDATE 29/02/2016
The DevTools docs have moved and the above link provides inaccurate information. The updated docs regarding Media type em...
Correct way to add external jars (lib/*.jar) to an IntelliJ IDEA project
...ps for adding external jars in IntelliJ IDEA:
Click File from the toolbar
Select Project Structure option (CTRL + SHIFT + ALT + S on Windows/Linux, ⌘ + ; on Mac OS X)
Select Modules at the left panel
Select Dependencies tab
Select + icon
Select 1 JARs or directories option
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How do I check in SQLite whether a table exists?
...sed that FAQ entry.
Anyway, for future reference, the complete query is:
SELECT name FROM sqlite_master WHERE type='table' AND name='{table_name}';
Where {table_name} is the name of the table to check.
Documentation section for reference: Database File Format. 2.6. Storage Of The SQL Database S...
How enumerate all classes with custom class attribute?
... faster (especially without empirical proof); you've basically written the Select extension method, and the compiler will generate a state machine just as it would if you called Select because of your use of yield return. Finally, any performance gains that might be obtained in the majority of case...
SQL order string as number
...u can't do that then cast your column value to an integer explicitly with
select col from yourtable
order by cast(col as unsigned)
or implicitly for instance with a mathematical operation which forces a conversion to number
select col from yourtable
order by col + 0
BTW MySQL converts strings...
Group by month and year in MySQL
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I prefer
SELECT
MONTHNAME(t.summaryDateTime) as month, YEAR(t.summaryDateTime) as year
FROM
trading_summary t
GROUP BY EXTRACT(YEAR_MONTH FROM t.summaryDateTime) DESC";
...
Dialog to pick image from gallery or from camera
...hoto and for picking a photo. Just show a dialog with two options and upon selection, use the appropriate code.
To take picture from camera:
Intent takePicture = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
startActivityForResult(takePicture, 0);//zero can be replaced with any action code (called ...
Get selected subcommand with argparse
When I use subcommands with python argparse, I can get the selected arguments.
2 Answers
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