Rules Reference

Rules in SQLFluff are implemented as crawlers. These are entities which work their way through the parsed structure of a query to evaluate a particular rule or set of rules. The intent is that the definition of each specific rule should be really streamlined and only contain the logic for the rule itself, with all the other mechanics abstracted away. To understand how rules are enabled and disabled see Enabling and Disabling Rules.

Core Rules

Certain rules belong to the core rule group. In order for a rule to be designated as core, it must meet the following criteria:

  • Stable

  • Applies to most dialects

  • Could detect a syntax issue

  • Isn’t too opinionated toward one style (e.g. the dbt style guide)

Core rules can also make it easier to roll out SQLFluff to a team by only needing to follow a ‘common sense’ subset of rules initially, rather than spending time understanding and configuring all the rules, some of which your team may not necessarily agree with.

We believe teams will eventually want to enforce more than just the core rules, and we encourage everyone to explore all the rules and customize a rule set that best suites their organization.

See the Configuration section for more information on how to enable only core rules by default.

Inline Ignoring Errors

SQLFluff features inline error ignoring. For example, the following will ignore the lack of whitespace surrounding the * operator.

a.a*a.b AS bad_1  -- noqa: LT01

Multiple rules can be ignored by placing them in a comma-delimited list.

a.a *  a.b AS bad_2,  -- noqa: LT01, LT03

It is also possible to ignore non-rule based errors, and instead opt to ignore templating (TMP) & parsing (PRS) errors.

WHERE
  col1 = 2 AND
  dt >= DATE_ADD(CURRENT_DATE(), INTERVAL -2 DAY) -- noqa: PRS

Note

It should be noted that ignoring TMP and PRS errors can lead to incorrect sqlfluff lint and sqfluff fix results as SQLFluff can misinterpret the SQL being analysed.

Should the need arise, not specifying specific rules to ignore will ignore all rules on the given line.

a.a*a.b AS bad_3  -- noqa

Ignoring line ranges

Similar to pylint’s “pylint” directive”, ranges of lines can be ignored by adding -- noqa:disable=<rule>[,...] | all to the line. Following this directive, specified rules (or all rules, if “all” was specified) will be ignored until a corresponding – noqa:enable=<rule>[,…] | all directive.

-- Ignore rule AL02 from this line forward
SELECT col_a a FROM foo -- noqa: disable=AL02

-- Ignore all rules from this line forward
SELECT col_a a FROM foo -- noqa: disable=all

-- Enforce all rules from this line forward
SELECT col_a a FROM foo -- noqa: enable=all

Rule Index