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How do I delete a fixed number of rows with sorting in PostgreSQL?
...
You could try using the ctid:
DELETE FROM logtable
WHERE ctid IN (
SELECT ctid
FROM logtable
ORDER BY timestamp
LIMIT 10
)
The ctid is:
The physical location of the row version within its table. Note that although the ctid can be used to locate the row version very quickly,...
How to open a specific port such as 9090 in Google Compute Engine
...hoose "Firewalls rules"
Choose "Create Firewall Rule"
To apply the rule to select VM instances, select Targets > "Specified target tags", and enter into "Target tags" the name of the tag. This tag will be used to apply the new firewall rule onto whichever instance you'd like. Then, make sure the ...
Computed / calculated / virtual / derived columns in PostgreSQL
...y as column?
The expression (looking like a column) is not included in a SELECT * FROM tbl, though. You always have to list it explicitly.
Can also be supported with a matching expression index - provided the function is IMMUTABLE. Like:
CREATE FUNCTION col(tbl) ... AS ... -- your computed expr...
How to style the option of an html “select” element?
...ed via CSS.
There are replacement plug-ins/libraries that look like a <select> but are actually composed of regular HTML elements that CAN be styled.
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Direct vs. Delegated - jQuery .on()
...green").on(), binds a click handler directly to the span(s) that match the selector at the moment that code is executed. This means if other spans are added later (or have their class changed to match) they have missed out and will not have a click handler. It also means if you later remove the "gre...
Check if option is selected with jQuery, if not select a default
Using jQuery, how do you check if there is an option selected in a select menu, and if not, assign one of the options as selected.
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How to achieve code folding effects in Emacs?
...on: C-h k C-x $
tells us that the above key combination is calling
set-selective-display, a function that takes one numerical argument
(the M-1 prefix passes 1 as the value of that argument) and,
unsurprisingly, sets the variable selective-display to the value of
that argument.
from mino...
Xcode + remove all breakpoints
...l breakpoints.
In Xcode4 press CMD(⌘)+6, in Xcode3 press CMD(⌘)+ALT+B.
Select all breakpoints with CMD(⌘)+A and delete them, like deleting text, with backspace.
There's no step 3 :)
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What is the use of GO in SQL Server Management Studio & Transact SQL?
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gbn make it SELECT and look at what happens :-)
– SQLMenace
Feb 19 '10 at 21:09
14
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Build unsigned APK file with Android Studio
...nu in the toolbar at the top (Open 'Edit Run/Debug configurations' dialog)
Select "Edit Configurations"
Click the "+"
Select "Gradle"
Choose your module as a Gradle project
In Tasks: enter assemble
Press Run
Your unsigned APK is now located in
ProjectName\app\build\outputs\apk
For detailed inf...