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quick random row selection in Postgres
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You might want to experiment with OFFSET, as in
SELECT myid FROM mytable OFFSET floor(random()*N) LIMIT 1;
The N is the number of rows in mytable. You may need to first do a SELECT COUNT(*) to figure out the value of N.
Update (by Antony Hatchkins)
You must use floor here:
SE...
How do I create a constant in Python?
...typing.Final variable annotation that will tell static type checkers (like mypy) that your variable shouldn't be reassigned. This is the closest equivalent to Java's final. However, it does not actually prevent reassignment:
from typing import Final
a: Final = 1
# Executes fine, but mypy will repo...
How do I get textual contents from BLOB in Oracle SQL
...xt, rather than view it, this works:
with unzipped_text as (
select
my_id
,utl_compress.lz_uncompress(my_compressed_blob) as my_blob
from my_table
where my_id='MY_ID'
)
select * from unzipped_text
where dbms_lob.instr(my_blob, utl_raw.cast_to_raw('MY_SEARCH_STRING'))>0;
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How can I convert a string to a number in Perl?
...t comparisons when the string has a comma in it?
– Ramy
May 22 '14 at 15:21
[rabdelaz@Linux_Desktop:~/workspace/akates...
Libraries not found when using CocoaPods with iOS logic tests
I am trying to write some iOS logic tests against classes in my project that use functionality from some of the libraries in my podspec. I am using the standard unit test bundle provided in Xcode (although not Application Tests, just Unit Tests).
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Why doesn't git recognize that my file has been changed, therefore git add not working
I am trying to push my files to github using bash. They are already on there, and I am uploading a newer version with new lines and code, etc. But when I try git add and then git status it says:
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Why aren't my breakpoints working?
... that said turn OFF Load Symbols Lazily.
I have two more things to add.
(My first suggestion sounds obvious, but the first time someone suggested it to me, my reaction went along these lines: "come on, please, you really think I wouldn't know better...... oh.")
Make sure you haven't accidentall...
Git hangs while writing objects
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omg, thank you for this! was pulling my hair out, and this solved my issues!
– Brett Thomas
Jun 15 '15 at 17:20
3
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Where is android studio building my .apk file?
I've been rebuilding my project from the ground up, so there's been a lot of problems with it. At the moment, everything's working great, except that when I try to run the app, I get the message 'Local path doesn't exist.' , where the local path is pointing at the path: AndroidStudioProjects\MyPro...
git: How do I get the latest version of my code?
I'm using Git 1.7.4.1. I want to get the latest version of my code from the repository, but I'm getting errors ...
10 Answ...