Library /sys$common/syshlp/RDOHELP72.HLB  —  Field attr, missing-value-clause
    Specifies a numeric or character string literal that denotes that
    no value is stored in the field. When you retrieve or display the
    value, Oracle Rdb returns the contents of the MISSING_VALUE string
    or number.

  (B)0missing-value-clause =

    qqqqq> MISSING_VALUE IS qqqwqqq> fxd-pnt-num qqqqqwqqq>
                               mqqq> quoted-string qqqj
Additional Information: explode extract

fxd-pnt-num
quoted-string
Examples
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