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What's the difference between django OneToOneField and ForeignKey?
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This answer says "there are some differences", and then names one difference. Are there others?
– Chris Martin
Aug 6 '14 at 8:35
6
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Importing two classes with same name. How to handle?
...t the answer of the question asked. If he (Roger) is developing that code, then definately he knows that he can change or refactor the name of his Class. What he is asking is different from the answer you gave.
– Yatendra Goel
Jan 17 '10 at 7:58
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What can be the reasons of connection refused errors?
...be upvoted. Once the obvious cause (nothing listening) has been resolved, then this is actually the most likely explanation, and fixing it can be a complex matter.
– Graham Nicholls
Nov 29 '17 at 12:11
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How do I calculate the normal vector of a line segment?
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if we define dx=x2-x1 and dy=y2-y1, then the normals are (-dy, dx) and (dy, -dx).
Note that no division is required, and so you're not risking dividing by zero.
share
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Git pull a certain branch from GitHub
... the branch you want to merge. For example, if you have this history tree, then merging other-branch would result in a fast-forward merge:
O-O-O-O-O-O
^ ^
master other-branch
However, this would not be a fast-forward merge:
v master
O-O-O
\
\-O-O-O-O
^ other-branch
To ...
IntelliJ - Convert a Java project/module into a Maven project/module
...t Intellij Idea (2017) takes some important settings only from the pom.xml then which can lead to some confusion, following sections are affected at least:
Annotation settings are changed for the modules
Compiler output path is changed for the modules
Resources settings are ignored totally and onl...
Vim: insert the same characters across multiple lines
...ntually times out. Two experiments for you: first, try pressing escape and then immediately pressing another key, like j or ^L. You should see that Vim wasn’t busy after all; it was just waiting. Second, try changing 'timeout' to a lower value, like 80 (rather than the default 1000) and observe th...
How do I get the current GPS location programmatically in Android?
...temService(Context.LOCATION_SERVICE);
Check if GPS is enabled or not.
And then implement LocationListener and get coordinates:
LocationListener locationListener = new MyLocationListener();
locationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER, 5000, 10, locationListener);
Here is t...
Is it possible to serialize and deserialize a class in C++?
...in the order in which two fields are written between versions of a program then we have an incompatibility. Is this right?
– Agnel Kurian
Jul 2 '13 at 8:19
1
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Number of rows affected by an UPDATE in PL/SQL
... has been performed within the current block, SQL%ROWCOUNT is set to null. Then it stays with the number of line affected by the last DML operation:
say we have table CLIENT
create table client (
val_cli integer
,status varchar2(10)
)
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We would test it this way:
begin
dbms_output.put_line...