!!! Overview
[{$pagename}] is a [LDAP Filter Choices] in which the [Assertion Value]=[Attribute Value] then entry is added to the [SearchResultEntry]

[{$pagename}] that can be used to identify entries that contain a specific [Attribute Value] for a given attribute. The server will use an [EQUALITY] [matching rule] to make the determination.

The string representation of an [LDAP] [{$pagename}] filter comprises an opening parenthesis followed by the attribute name, an equal sign, the attribute value, and the closing parenthesis. 

For [example], an [{$pagename}] filter of 
{{{
(uid=john.doe)
}}}
will match any entry in which the uid attribute contains a value of john.doe.

!! More Information
There might be more information for this subject on one of the following:
[{ReferringPagesPlugin before='*' after='\n' }]
----
* [#1] - [equality search filter|https://docs.oracle.com/cd/E19623-01/820-6173/def-equality-search-filter.html|target='_blank'] - based on information obtained 2018-10-03-