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How do I get IntelliJ to recognize common Python modules?
...le -> Project Structure -> Project -> Project SDK -> new
and select the installation path of your Python interpreter (for
example, C:\Python26 in windows and /usr/bin/python2.7 in Linux) as the home path.
Related discussion: http://devnet.jetbrains.net/thread/286883
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How to check if mysql database exists
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SELECT SCHEMA_NAME
FROM INFORMATION_SCHEMA.SCHEMATA
WHERE SCHEMA_NAME = 'DBName'
If you just need to know if a db exists so you won't get an error when you try to create it, simply use (From here):
CREATE DATABASE IF NO...
SQL Inner-join with 3 tables?
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You can do the following (I guessed on table fields,etc)
SELECT s.studentname
, s.studentid
, s.studentdesc
, h.hallname
FROM students s
INNER JOIN hallprefs hp
on s.studentid = hp.studentid
INNER JOIN halls h
on hp.hallid = h.hallid
Based on your request for ...
What's the difference between a temp table and table variable in SQL Server?
...-unique indexes too.
Table variables don't participate in transactions and SELECTs are implicitly with NOLOCK. The transaction behaviour can be very helpful, for instance if you want to ROLLBACK midway through a procedure then table variables populated during that transaction will still be populated...
sql query to return differences between two tables
...colum C, here are the records, which are present in table A but not in B:
SELECT A.*
FROM A
LEFT JOIN B ON (A.C = B.C)
WHERE B.C IS NULL
To get all the differences with a single query, a full join must be used, like this:
SELECT A.*, B.*
FROM A
FULL JOIN B ON (A.C = B.C)
WHERE A.C IS NUL...
select * vs select column
If I just need 2/3 columns and I query SELECT * instead of providing those columns in select query, is there any performance degradation regarding more/less I/O or memory?
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Right query to get the current number of connections in a PostgreSQL DB
...ires aren't equivalent. The equivalent version of the first one would be:
SELECT sum(numbackends) FROM pg_stat_database;
In that case, I would expect that version to be slightly faster than the second one, simply because it has fewer rows to count. But you are not likely going to be able to measu...
How to convert a selection to lowercase or uppercase in Sublime Text
I have several strings selected in a file in Sublime Text and I want to convert them all to lowercase.
5 Answers
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Default filter in Django admin
...lookup, title in self.lookup_choices:
yield {
'selected': self.value() == lookup,
'query_string': cl.get_query_string({
self.parameter_name: lookup,
}, []),
'display': title,
}
def querys...
Autocomplete applying value not label to textbox
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The default behavior of the select event is to update the input with ui.item.value. This code runs after your event handler.
Simply return false or call event.preventDefault() to prevent this from occurring. I would also recommend doing something simi...