Evaluates two Period expressions or derived periods to TRUE, FALSE, or UNKNOWN.
Result Type
This predicate applies when both period_expression_1 and period_expression_2 are a period column, period constructor, or period value expression. In this case, the predicate returns True if the begin bound value of period_expression_1 is equal to the end bound value of period_expression_2 If either or both of the operands are NULL, the result is UNKNOWN.
If either expression is NULL, the operator returns UNKNOWN.