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What is the difference between “INNER JOIN” and “OUTER JOIN”?
...he intersection of the two tables, i.e. the two rows they have in common.
select * from a INNER JOIN b on a.a = b.b;
select a.*, b.* from a,b where a.a = b.b;
a | b
--+--
3 | 3
4 | 4
Left outer join
A left outer join will give all rows in A, plus any common rows in B.
select * from a LEFT OUT...
HTML select form with option to enter custom value
...users can enter custom text value or choose from drop down. A regular <select> only offers drop down options.
6 Ans...
Disable individual Python unit tests temporarily
...-excursion
(beginning-of-line)
(search-forward "def")
(forward-char)
(if (looking-at "disable_")
(zap-to-char 1 ?_)
(insert "disable_"))))
share
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improve this answer
...
What's the fastest algorithm for sorting a linked list?
...is best, followed by Quicksort and Mergesort. Sediment sort, bubble sort, selection sort perform very badly.
A COMPARATIVE STUDY OF LINKED LIST SORTING ALGORITHMS
by Ching-Kuang Shene
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.31.9981
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What is in your .vimrc? [closed]
...
is there any way to select from more colors?
– Fzs2
Aug 13 '10 at 10:13
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Uncaught SyntaxError: Unexpected token with JSON.parse
...l getting this...
In that case it's likely that there are hidden/special characters in the string from whatever source your getting them. When you paste into a validator, they are lost - but in the string they are still there. Those chars, while invisible, will break JSON.parse()
If s is your raw...
Get list of databases from SQL Server
...
Execute:
SELECT name FROM master.sys.databases
This the preferred approach now, rather than dbo.sysdatabases, which has been deprecated for some time.
Execute this query:
SELECT name FROM master.dbo.sysdatabases
or if you pref...
How can I select an element with multiple classes in jQuery?
I want to select all the elements that have the two classes a and b .
13 Answers
13...
Insert, on duplicate update in PostgreSQL?
...try the UPDATE again
END;
END LOOP;
END;
$$
LANGUAGE plpgsql;
SELECT merge_db(1, 'david');
SELECT merge_db(1, 'dennis');
There's possibly an example of how to do this in bulk, using CTEs in 9.1 and above, in the hackers mailing list:
WITH foos AS (SELECT (UNNEST(%foo[])).*)
updated...
How to use count and group by at the same select statement
I have an sql select query that has a group by.
I want to count all the records after the group by statement.
Is there a way for this directly from sql?
For example, having a table with users I want to select the different towns and the total number of users
...