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Some of the basic OFBiz temporal expressions are ranges - which simplifies expression creation. For example, if an event occurs every Monday, Tuesday, and Wednesday, you could create an expression for each day and make them members of a Union expression, or you could use a single Day Of Week Range expression that includes Monday through Wednesday.
Sometimes recurring events need to be rescheduled, like when they fall on a holiday, or when maintenance is being performed. The Substitution expression can be used to reschedule recurring events.
Basic Expressions
Expression Collections
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