The schema is SYSIBM.
The ARRAY_PRIOR function returns the next smaller array index value for an array relative to the specified array index argument.
The result is the next smaller array index value defined in the array relative to the specified array-index value. If array-index is greater than the maximum index array value in the array, the result is the last array index value defined in the array.
The data type of the result of the function is the data type the array index. The result can be null; if either argument is null, the cardinality of the first argument is zero, or the value of array-index is less than or equal to the value of the first index in the array, the result is the null value.
SET PREV_CONSTIDX = ARRAY_PRIOR(SPECIALNUMBERS,2)
The result is 1.SET X = ARRAY_PRIOR(PHONELIST, 'Work')
The
value of 'Mom' is assigned to X.
Assign the value of the index in the array that is the previous index
before index value'Home':SET X = ARRAY_PRIOR(PHONELIST, 'Home')
The null value is assigned to X.