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Why would someone use WHERE 1=1 AND in a SQL clause?
Why would someone use WHERE 1=1 AND <conditions> in a SQL clause (Either SQL obtained through concatenated strings, either view definition)
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Which one will execute faster, if (flag==0) or if (0==flag)?
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I haven't seen any correct answer yet (and there are already some) caveat: Nawaz did point out the user-defined trap. And I regret my hastily cast upvote on "stupidest question" because it seems that many did not get it right and it gives room for a nice discussio...
django : using select_related and get_object_or_404 together
Is there any way of using get_object_or_404 and select_related together or any other way to achieve the result of using these two together(except from putting it in try/except)??
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Wait for a process to finish
... solution for MacOS that does not use polling.
– Alexander Mills
Feb 28 '18 at 16:58
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Insert into a MySQL table or update if exists
...m what I've found, this method is less problematic for auto-increment keys and other unique key collisions than REPLACE INTO, and it is more efficient.
– Andrew Ensley
May 11 '12 at 21:27
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What are the differences between “=” and “
What are the differences between the assignment operators = and <- in R?
7 Answers
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Is there an easy way to pickle a python function (or otherwise serialize its code)?
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You could serialise the function bytecode and then reconstruct it on the caller. The marshal module can be used to serialise code objects, which can then be reassembled into a function. ie:
import marshal
def foo(x): return x*x
code_string = marshal.dumps(foo.func...
What is the correct SQL type to store a .Net Timespan with values > 24:00:00?
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I'd store it in the database as a BIGINT and I'd store the number of ticks (eg. TimeSpan.Ticks property).
That way, if I wanted to get a TimeSpan object when I retrieve it, I could just do TimeSpan.FromTicks(value) which would be easy.
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Save PL/pgSQL output from PostgreSQL to a CSV file
...ing easy to re-use or automate, you can use Postgresql's built in COPY command. e.g.
Copy (Select * From foo) To '/tmp/test.csv' With CSV DELIMITER ',' HEADER;
This approach runs entirely on the remote server - it can't write to your local PC. It also needs to be run as a Postgres "superuser" (no...
Running Bash commands in Python
...cess. From the docs: "This module intends to replace several older modules and functions: os.system, os.spawn".
Like in your case:
bashCommand = "cwm --rdf test.rdf --ntriples > test.nt"
import subprocess
process = subprocess.Popen(bashCommand.split(), stdout=subprocess.PIPE)
output, error = pr...