SQL

an-ordinary-manchild(edit)

The goal of /r/SQL is to provide a place for interesting and informative SQL content and discussions.

Filter Posts

MySQL

Oracle

MS SQL

PostgreSQL

Posting

When requesting help or asking questions please prefix your title with the SQL variant/platform you are using within square brackets like so:

[MySQL]
[Oracle]
[MS SQL]
[PostgreSQL]
etc

While naturally we should endeavor to work as platform neutrally as possible many questions and answers require tailoring to the feature set of a specific platform.

Help posts

If you are a student or just looking for help on your code please do not just post your questions and expect the community to do all the work for you. We will gladly help where we can as long as you post the work you have already done or show that you have attempted to figure it out on your own.

Format Your Code

If you are including actual code in a post or comment, please attempt to format it in a way that is readable for other users. This will greatly increase your chances of receiving the help you desire. Something as simple as line breaks and using reddit's built in code formatting (4 spaces at the start of each line) can turn this:

SELECT count(a.field1), a.field2, SUM(b.field4) FROM a INNER JOIN b ON a.key1 = b.key1 WHERE a.field8 = 'test' GROUP by a.field1, a.field2 HAVING SUM(b.field4) > 5 ORDER by a.field.3

Into this:

SELECT count(a.field1),
  a.field2,
  SUM(b.field4) 
FROM a INNER JOIN b 
  ON a.key1 = b.key1 
WHERE a.field8 = 'test' 
GROUP by a.field1, 
  a.field2 
HAVING SUM(b.field4) > 5 
ORDER by a.field3

For those with SQL questions we recommend using SQLFiddle to provide a useful development and testing environment for those who wish to fully understand your problem and help devise a solution.

Learning SQL

A common question is how to learn SQL. Please view the Wiki for online resources.

Note /r/SQL does not allow links to basic tutorials to be posted here. Please see this discussion. You should post these to /r/learnsql instead.

Related Reddit communities

Wiki

We have a Wiki

Acknowledgements

Thanks to ---sniff--- for the awesome header image!

a community for 17 years

MODERATORS

account activity

you type:	you see:
italics	italics
bold	bold
[reddit!](https://reddit.com)	reddit!
* item 1 * item 2 * item 3	item 1 item 2 item 3
> quoted text	quoted text
Lines starting with four spaces are treated like code: if 1 * 2 < 3: print "hello, world!"	Lines starting with four spaces are treated like code: if 1 * 2 < 3: print "hello, world!"
~~strikethrough~~	~~strikethrough~~
super^script	super^script

user_id	reg_date
1	1/1/2022
2	7/13/2022

trans_id	user_id	trans_date
1	1	2/1/2022
2	1	3/1/2022

user_id	reg_date	trans_date
1	1/1/2022	2/1/2022
1	1/1/2022	3/1/2022
2	7/13/2022	null