Behaviour Of

The behaviour of DECFLOAT operations in a session, specifically rounding and error behaviour, can be configured using the SET DECFLOAT management statement, and the isc_dpb_decfloat_round and isc_dpb_decfloat_traps DPB items.

It is possible to express DECFLOAT(34) values in approximate numeric literals, but only for values with a mantissa of 20 or more digits, or an absolute exponent larger than 308.Scientific notation literals with fewer digits or a smaller absolute exponent are DOUBLE PRECISION literals.Exact numeric literals with 40 or more digits — actually 39 digits, when larger than the maximum INT128 value — are also handled as DECFLOAT(34).

Alternatively, use a string literal and explicitly cast to the desired DECFLOAT type.

The length of DECFLOAT literals cannot exceed 1024 characters.Scientific notation is required for greater values.For example, 0.0<1020 zeroes>11 cannot be used as a literal, but the equivalent in scientific notation, 1.1E-1022, is valid.Similarly, 10<1022 zeroes>0 can be presented as 1.0E1024.Literals with more than 34 significant digits are rounded using the DECFLOAT rounding mode of the session.