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Active Record Query Logs

Automatically tag SQL queries with runtime information.

Default tags available for use:

  • application

  • pid

  • socket

  • db_host

  • database

_Action Controller and Active Job tags are also defined when used in Rails:_

  • controller

  • action

  • job

The tags used in a query can be configured directly:

ActiveRecord::QueryLogs.tags = [ :application, :controller, :action, :job ]

or via Rails configuration:

config.active_record.query_log_tags = [ :application, :controller, :action, :job ]

To add new comment tags, add a hash to the tags array containing the keys and values you want to add to the comment. Dynamic content can be created by setting a proc or lambda value in a hash, and can reference any value stored in the context object.


tags = [
    custom_tag: ->(context) { context[:controller]&.controller_name },
    custom_value: -> { Custom.value },
ActiveRecord::QueryLogs.tags = tags

The QueryLogs context can be manipulated via the ActiveSupport::ExecutionContext.set method.

Temporary updates limited to the execution of a block:

ActiveSupport::ExecutionContext.set(foo: do
  posts = Post.all

Direct updates to a context value:

ActiveSupport::ExecutionContext[:foo] =

Tag comments can be prepended to the query:

ActiveRecord::QueryLogs.prepend_comment = true

For applications where the content will not change during the lifetime of the request or job execution, the tags can be cached for reuse in every query:

ActiveRecord::QueryLogs.cache_query_log_tags = true

This option can be set during application configuration or in a Rails initializer:

config.active_record.cache_query_log_tags = true