Algorithm for neatly indenting SQL statements (Python implementation would be nice)

Question

I'd like to reformat some SQL statements that are a single string with newlines in to something that's much easier to read.

I don't personally know of a good coding style for indenting SQL - how should nested queries / where clauses / left joins / etc by represented to maximise readability?

Has anyone seen a pretty-printing algorithm that does this already? In Python would be even better.

score 41 · Accepted Answer · edited Jun 03 '22 at 16:52

41

You can try sqlparse. It's a Python module that provides simple SQL formatting. A online demo is available here.

edited Jun 03 '22 at 16:52

JL Peyret

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answered Apr 28 '09 at 14:59

Andi Albrecht

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And I just noticed that it is your app. – James McMahon Apr 28 '09 at 18:36
@nemo: Giving the best to hide myself, but Web2.0 always displays the same picture anywhere ;-) – Andi Albrecht Apr 28 '09 at 19:00
how to use it offline in web app ? it don't describe in web docs / git, thanks – haidarvm Apr 04 '18 at 23:27
No longer found on Google Code. New source URL at GitHub: https://github.com/andialbrecht/sqlparse and the Demo is now found at: https://sqlformat.org/ – ericx Aug 05 '20 at 15:00

score 3 · Answer 2 · answered Apr 28 '09 at 14:25

3

I personally use SQL Inform for quick SQL formating, which is written in Java and is unfortunately not open source, so there is no access to the underlying algorithm.

answered Apr 28 '09 at 14:25

James McMahon

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score 3 · Answer 3 · edited May 23 '17 at 12:34

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Perhaps part of the difficulty in finding a tool is that there are so many different "standard" SQL formatting conventions. Here are two SO questions that describe people's preferences:

edited May 23 '17 at 12:34

Community

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answered Apr 28 '09 at 14:35

yukondude

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score 2 · Answer 4 · answered May 15 '13 at 14:20

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I have previously used SQL Complete by Devart for formatting SQL, but now there is a free online SQL beautifier powered by SQL Complete - SQL Formatter it is really feature rich and easy to use even for a beginner.

answered May 15 '13 at 14:20

Marina Nastenko

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score -2 · Answer 5 · answered Apr 28 '09 at 14:49

-2

Don't know if it answers your question, but I generally use this strategy

SELECT what1, what2, etc,
FROM table
WHERE condition
  AND condition
  AND condition
ORDER BY whatever

But that's just me. I don't think proper automatic tools exist.

answered Apr 28 '09 at 14:49

Stefano Borini

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Algorithm for neatly indenting SQL statements (Python implementation would be nice)

5 Answers5