如何将嵌套的 IFF 语句重写为 oracle case when 语句

Question

如何将以下嵌套的 IFF 语句重写为 oracle Case when 语句。

IIF(IN_RNK = 1,
IIF(IN_SUM > 2,IIF(IN_MTR_COVERAGE_NUMBER_A = 'A','ORIGINAL BASE','ORIGINAL RIDER'),IN_MTR_COVERAGE_NUMBER_A),
IN_MTR_COVERAGE_NUMBER_A)

Answer 1

像这样：

CASE
WHEN in_rnk = 1 AND in_sum > 2 AND in_mtr_coverage_number_a = 'A'
THEN 'ORIGINAL BASE'
WHEN in_rnk = 1 AND in_sum > 2
THEN 'ORIGINAL RIDER'
ELSE in_mtr_coverage_number_a
END