dhmax Routine--Create Default Maximum Histogram Value
This routine creates the default maximum histogram value. The default histogram values are used by the optimizer when no histogram data is present in the system catalogs. For a discussion of creating a default histogram routine, see dhmin Routine. If the II_DT_NOHISTOGRAM attribute is set, then this routine is not necessary.
This routine and the hmax routine form a pair, similar to the pair hmin and dhmin, except that hmax and dhmax deal with the maximum and default maximums, respectively, instead of the minimums.
Place the address of this routine in the dtd_dhmax_addr field of the IIADD_DT_DFN structure.
Inputs
The inputs for this function are:
scb
Pointer to an SCB
dv_from
Pointer to a datavalue containing the type for the value
dv_histogram
Pointer to a datavalue for the histogram
Outputs
The outputs for this function are:
*(dv_histogram-db_data)
Filled with the histogram value
Returns
II_STATUS
Last modified date: 08/14/2024