Help: Tag Relationships

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Contents: Aliases | Implications | Bulk Update Requests

Tag Relationships

Tags can be automatically added or replaced. This is done via aliases and implications.


Sometimes, two tags can mean the exact same thing. For example, girl and female have identical meanings.
It makes sense that if you search for one, you should also get the results for the other.

e621 tries to fix this issue by using tag aliases. You can alias one or more tags to one reference tag.
For example, if we aliased girl to female, then whenever someone searched for (or tagged a post with) girl, it would be internally replaced with female.

You can have multiple tags aliased to the same tag, but you cannot have one tag aliased to multiple other tags.

While anyone can suggest an alias, only an administrator can approve it.


Tag implications can be used to describe is-a relationships.

Let's imagine that you tag a post with eagle. Eagles are simply a type of bird, so ideally, and you would like people who search for bird to see your eagle post.
You could tag your post with both eagle and bird, but this starts to get tedious after a while.
When an eaglebird implication is created, whenever someone tags a post with eagle, e621 will also tag it with bird.

Tag implications have an antecedent and a consequent.
The antecedent is what is matched against. In the previous example, it would be eagle. The consequent is the tag that is added. In the example, it would be bird.

A tag can imply multiple consequents, and e621 will just add all of them to the post.
For example, if we created a eagleavian implication, then anytime someone tagged a post with eagle it would be expanded to eagle bird avian.

Implications can also be chained together. Instead of eagle -> avian we could create a bird -> avian implication. The end result would be the same.

It's easy to go overboard with implications. It's important not to create implications for frivolous things.
For example, we could theoretically implicate everything to an object tag, but this is pointless and only adds bloat to the database.

While you can suggest new implications, only an administrator can approve them.

Bulk Update Requests

Bulk Update Request or simply BUR for shot is a not a unique tag relationship type, but instead a mechanism to perform multiple aliases and implications in a single request.
Users can write a script, and an administrator is able to approve or disapprove the request.

You can request a BUR in the menu over the Forum page, or clicking here.

Available actions

The current actions possible are:

  • alias: Creates a new alias
  • imply: Creates a new implication
  • unalias: Removes an existing alias
  • unimply: Removes an existing implication
  • update: Replaces every single use of a tag with another, but only once
  • category: Changes the category of a tag

The syntax of a BUR looks like this:

unalias aaa -> bbb
unimply aaa -> bbb
alias aaa -> bbb
imply aaa -> bbb
update aaa -> bbb
category tag_name -> category_name
Warning messages

A BUR can give warning messages depending on already existing requests. An example is:

# duplicate of has blocking transitive relationships

These errors can appear on new implications or aliases, and means the target of them is already involved in some older requests. For this to work, the previous requests would need to be rejected first.

When the BUR refuses to submit because of an error, you can simply remove the lines causing the issue, and put them in the forum post, requesting a staff member to perform it after the BUR runs.