The FIRST FROM expression works in two steps:

    o  It forms the record stream as specified by the record
       selection expression.

    o  If at least one record matches the RSE, Oracle Rdb uses the
       values stored in the first record of the record stream to
       evaluate the value expression.

    Format

  (B)0first-from-expr

    qqq> FIRST qqq> value-expr qqq> FROM qqq> rse qqq>