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Postgres and Indexes on Foreign Keys and Primary Keys
Does Postgres automatically put indexes on Foreign Keys and Primary Keys? How can I tell? Is there a command that will return all indexes on a table?
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SQL Server insert if not exists best practice
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Semantically you are asking "insert Competitors where doesn't already exist":
INSERT Competitors (cName)
SELECT DISTINCT Name
FROM CompResults cr
WHERE
NOT EXISTS (SELECT * FROM Competitors c
WHERE cr.Name = c.cName...
MySQL: Fastest way to count number of rows
...olumn indexes, so it will be the best result. Mysql with MyISAM engine actually stores row count, it doensn't count all rows each time you try to count all rows. (based on primary key's column)
Using PHP to count rows is not very smart, because you have to send data from mysql to php. Why do it whe...
Official way to ask jQuery wait for all images to load before executing something
... DOM is loaded and $(window).on("load", handler) to execute something when all other things are loaded as well, such as the images.
The difference can be seen in the following complete HTML file, provided you have a jollyroger JPEG files (or other suitable ones):
<html>
<head>
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Get all table names of a particular database by SQL query?
... Server and MySQL 2) INFORMATION_SCHEMA.TABLES exists only in MySQL 3) I really wonder how comes you got so many upvotes for this ...
– Apostolos
Dec 14 '18 at 11:04
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How to unmount a busy device
...ared drives (from a SQL table) and mount them in a special directory where all users can access them.
11 Answers
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Duplicate and rename Xcode project & associated folders [closed]
...the associated files without Xcode going mental, and without having to manually re-import all files to the project.
9 Answe...
git: undo all working dir changes including new files
How to delete all changes from working directory including new untracked files. I know that git checkout -f does that, but it doesn't delete new untracked files created since last commit.
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Algorithms based on number base systems? [closed]
...ctional Data Structures that discusses "Numerical Representations": essentially, take some representation of a number and convert it into a data structure. To give a flavor, here are the sections of that chapter:
Positional Number Systems
Binary Numbers (Binary Random-Access Lists, Zeroless Repres...
Making a private method public to unit test it…good idea?
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Note:
This answer was originally posted for the question Is unit testing alone ever a good reason to expose private instance variables via getters? which was merged into this one, so it may be a tad specific to the usecase presented there.
As a gener...
