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What is the difference between “INNER JOIN” and “OUTER JOIN”?
...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 OUTER JOIN b on a.a = b.b;
select a.*, b.* from a,b where a.a = b.b(+);
a | b
--+-----
1 | null
2 | null
3 | 3
4 | 4
Right outer join
A right outer j...
argparse: identify which subparser was used [duplicate]
... method on the sub parser to solve this problem.
For example, I've added calls to set_defaults() to your code:
import argparse
parser = argparse.ArgumentParser( version='pyargparsetest 1.0' )
subparsers = parser.add_subparsers(help='commands')
# all
all_parser = subparsers.add_parser('all', help...
Zoom to fit all markers in Mapbox or Leaflet
How do I set view to see all markers on map in Mapbox or Leaflet ? Like Google Maps API does with bounds ?
8 Answers
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Printing the value of a variable in SQL Developer
...
Make server output on First of all
SET SERVEROUTPUT on then
Go to the DBMS Output window (View->DBMS Output)
then Press Ctrl+N for connecting server
share
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How to find all combinations of coins when given some dollar value
...or this, and contains a fairly extensive discussion of the problem. Essentially you define a polynomial where the nth coefficient is the number of ways of making change for n dollars.
Pages 4-5 of the writeup show how you can use Mathematica (or any other convenient computer algebra system) to comp...
What's the difference between git clone --mirror and git clone --bare
...
The difference is that when using --mirror, all refs are copied as-is. This means everything: remote-tracking branches, notes, refs/originals/* (backups from filter-branch). The cloned repo has it all. It's also set up so that a remote update will re-fetch everything f...
List all environment variables from the command line
Is it possible to list all environment variables from a Windows' command prompt?
8 Answers
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Print a list of all installed node.js modules
In a node.js script that I'm working on, I want to print all node.js modules (installed using npm) to the command line. How can I do this?
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How can you represent inheritance in a database?
...to tackle inheritance is to create a new table for each subtype, repeating all the common attributes in each table. For example:
--// Table: policies_motor
+------+---------------------+----------------+
| id | date_issued | vehicle_reg_no |
+------+---------------------+----------------+
...
Remove large .pack file created by git
...till get it back by accessing the history.
What you are looking to do is called rewriting history, and it involved the git filter-branch command.
GitHub has a good explanation of the issue on their site. https://help.github.com/articles/remove-sensitive-data
To answer your question more directly,...