XPath injection doubt

[Anne Beckman <anne.beckman () gmail com>]

I am learning the XPath injection technique. To bypass authentication,
we give a string like:

hi' or 1=1 or 'hey'='hello

I noticed that the equivalent string in SQL Injection would have been shorter:

hi' or 1=1--

I understand that XPath does not have comments, so we cannot use the
-- technique to comment out the rest of the query. But how does that
additional OR clause with 'hey'='hello solve the problem too?

Thank-you,
Anne

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