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How to concatenate strings of a string field in a PostgreSQL 'group by' query?
...way to concatenate the strings of a field within a group by query. So for example, I have a table:
14 Answers
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Size-limited queue that holds last N elements in Java
... libraries: is there a ready-made class that implements a Queue with a fixed maximum size - i.e. it always allows addition of elements, but it will silently remove head elements to accomodate space for newly added elements.
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PostgreSQL Autoincrement
...t values. I saw in the PostgreSQL docs a datatype "serial", but I get syntax errors when using it (in v8.0).
11 Answers
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Search stops working for “Entire Solution”
... has stopped working for me. Anytime I search "Entire Solution" for some text I get this result:
28 Answers
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Understanding colors on Android (six characters)
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If you provide 6 hex digits, that means RGB (2 hex digits for each value of red, green and blue).
If you provide 8 hex digits, it's an ARGB (2 hex digits for each value of alpha, red, green and blue respectively).
So by removing the final 55 ...
Convert PDF to image with high resolution
...\
test.pdf \
-quality 100 \
-flatten \
-sharpen 0x1.0 \
24-18.jpg
It results in the left image. Compare this to the result of my original command (the image on the right):
(To really see and appreciate the differences between the two, right-click on each and se...
How to replace a string in multiple files in linux command line
...aced with "bar".
On BSD systems like macOS, you need to provide a backup extension like -i '.bak' or else "risk corruption or partial content" per the manpage.
cd /path/to/your/folder
sed -i '.bak' 's/foo/bar/g' *
share
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Android studio using > 100% CPU at all times - no background processes appear to be running
... it appears there are no background processes that the IDE is running (indexing, etc). I might suspect this were something specific to my box, but some fellow developers are encountering this as well.
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NameError: name 'self' is not defined
... chosen for the first argument. You can as well replace "self" by "me" or "x".
– Max
May 22 '19 at 20:41
Is there no b...
What is the best way to conditionally apply a class?
... li for each element and a property on the controller called selectedIndex . What would be the best way to add a class to the li with the index selectedIndex in AngularJS?
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