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What is a proper naming convention for MySQL FKs?
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Example:
CREATE TABLE users(
user_id int,
name varchar(100)
);
CREATE TABLE messages(
message_id int,
user_id int
);
ALTER TABLE messages ADD CONSTRAINT fk_messages_users_user_id
FOREIGN KEY (user_id) REFERENCES users(user_id);
I try to stick with the same fie...
MySQL select 10 random rows from 600K rows fast
How can I best write a query that selects 10 rows randomly from a total of 600k?
26 Answers
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How to detect the physical connected state of a network cable/connector?
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edited Feb 19 '19 at 10:47
Ricky Robinson
16.3k3434 gold badges104104 silver badges163163 bronze badges
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Deleting all files in a directory with Python
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answered Jan 3 '10 at 16:02
mikumiku
153k4141 gold badges276276 silver badges293293 bronze badges
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What is pseudopolynomial time? How does it differ from polynomial time?
...orithm to have to do a lot of work. If I write out an input like this:
10001010101011
then it will take some worst-case amount of time, say T, to complete. If I now add a single bit to the end of the number, like this:
100010101010111
The runtime will now (in the worst case) be 2T. I can...
How can I quantify difference between two images?
....py one.jpg one-blurred.jpg
Manhattan norm: 92605183.67 / per pixel: 13.4210411116
Zero norm: 6900000 / per pixel: 1.0
P.S. Entire compare.py script.
Update: relevant techniques
As the question is about a video sequence, where frames are likely to be almost the same, and you look for something ...
Python creating a dictionary of lists
...ult value.
– nimcap
Apr 1 '19 at 12:10
add a comment
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Is it a good idea to index datetime field in mysql?
... case?
– cronoklee
Nov 22 '18 at 18:10
hi @Explosion Pills, if I only need to query the table base on year and month, ...
How to create SBT project with IntelliJ Idea?
...nce them, use command gen-idea no-classifiers no-sbt-classifiers.
SBT 0.10.1
(according to the plugin author, 0.10.0 won't work!)
Create and add the following lines to ~/.sbt/plugins/build.sbt:
resolvers += "sbt-idea-repo" at "http://mpeltonen.github.com/maven/"
libraryDependencies += "com.git...
What is the best way to create constants in Objective-C
...taticConst will.
– Ben Leggiero
Mar 10 '16 at 19:47
Does it make sense in spelling like static NSString *const instead...