Cypher equivalent of OPTIONAL MATCH in nGQL

[porscheme]

Hi @wey-gu , Is there nGQL equivalent of Cypher OPTIONAL MATCH?
Thanks

Since below cypher graph walk is vary slow, we want try using nGQL.

MATCH (p:Student)
WHERE id(p) IN [ ... ]

OPTIONAL MATCH (p)<-[:HAS_COURSE]-(a:CourseCodes)
OPTIONAL MATCH (p)<-[:STUDENT_HAS_SOCIAL]-(s:Social)
OPTIONAL MATCH (p)<-[:HAS_PROCEDURE]-(r:ProcedureCodes)

WITH
  p,
  COLLECT(DISTINCT a.CourseCodes.CodeId) as courses,
  COLLECT(DISTINCT s.Social.AttributeId) as social,
  COLLECT(DISTINCT r.ProcedureCodes.CodeId) as procedures

RETURN 
  p.Student.StudentId as Student, 
  p.Student.Gender as sex, 
  p.Student.Race as race, 
  p.Student.Ethnicity as ethnicity, 
  p.Student.MaritalStatus as maritalstatus,
  diagnosis,
  procedures,
  social