Embedded Query Language (EQL) segment -- HL7v2 v2.5.1.
Withdrawn/deprecated query segment from v2.3 that still appears in the v2.5.1 index. Carries an embedded query statement.
4 fields per HL7 v2.5.1 specification.
@type t() :: %HL7v2.Segment.EQL{ eql_query_name: term(), eql_query_statement: term(), extra_fields: term(), query_response_format_code: term(), query_tag: term() }