Return a field value from the first or last record in the result set returned by a query.
First( expr )
Last( expr )
The expr placeholder represents a string expression identifying the field that contains the data you want to use or an expression that performs a calculation using the data in that field. Operands in expr can include the name of a table field, a constant, or a function (which can be either intrinsic or user-defined but not one of the other SQL aggregate functions).
These functions return the value of a specified field in the first or last record, respectively, of the result set returned by a query. If the query does not include an ORDER BY clause, the values returned by these functions will be arbitrary because records are usually returned in no particular order.