Sequence Queries - What is a predicate in this context?

[Lilly]

Hello friends!

So I'm working on this report on optimizing sequence queries and I'm specifically studying SQL TS (SQL for Time Series). It's basically an extension for SQL for finding patterns in sequences. So I need help to translate this phrase into English, because I really have no idea what it means:

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Thus, a star pattern such as ∗Y fails only when the predicates that become fully instantiated at Y fail on the first input. However, if such predicates succeed on the first n ≥ 1 tuples and fail on tuple n+1, then ∗Y succeed and completes on the nth tuple, and the n+1 tuple is tested against the element in the pattern immediately following ∗Y

What is a predicate?

What is a fully instantiated predicate?

Thank you in advance!

[Ocean West]

In database terms:

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Is an expression that evaluates to TRUE, FALSE, or UNKNOWN. Predicates are used in the search condition of WHERE clauses and HAVING clauses, the join conditions of FROM clauses, and other constructs where a Boolean value is required.

in FileMaker terms a predicate is one or more fields used as parent or foreign keys between two table occurrences.