Flake8-SQL is a flake8 plugin that looks for SQL queries and checks then against an opinionated style. This style mostly follows SQL Style Guide, but differ in the two following ways. Firstly alignement should be with the INTO rather than INSERT keyword, i.e.

INSERT INTO table (columns)
     VALUES (values)

Secondly JOIN should be aligned to the left of the river, i.e.

SELECT *
  FROM table1
  JOIN table2 ON ...

All the SQL reserved keywords should be uppercase.

All the non SQL keywords should be snake_case, start with a letter and not end with an _. Due to a limitation snake_case is checks ensure that the word is lowercase.

Avoid using abbreviated keywords instead use the full length version.

Commas should be followed by whitespace, but not preceded.

Equals should be surrounded with whitespace.

The root keywords SELECT, FROM, INSERT, VALUES, DELETE FROM, WHERE, UPDATE, AND, OR and SET should be on separate lines (unless the entire query is on one line).

Semicolons must be at the end of the line.

The root keywords SELECT, FROM, INSERT, VALUES, WHERE, UPDATE, AND, OR, JOIN and SET should be right aligned i.e.

SELECT *
  FROM table

Any subquery should be aligned to the right of the river i.e.

SELECT *
  FROM table
 WHERE column IN
       (SELECT column
          FROM table)

Any tokens should be aligned to the right of the river i.e

SELECT column1,
       column2
  FROM table

At times it is simpler to use a reserved keyword as an identifier than go to the effort to avoid it. To allow for this set the sql-excepted-names option to a comma separated list of these names.

String constants are sought out in the code and considered SQL if they contain select from, insert into values, update set or delete from in order. This may and is likely to lead to false positives, in which case simply add # noqa to have this plugin ignore the string.

F-Strings are formatted with the formatted values, {...}, replaced with the constant formatted_value before being linted. This leads to the error message referring to formatted_value rather than what was actually written.