odbtools/odbctest/mql/aaa/13aggregate/14distinct.mql

-- ============================================================
-- count(distinct ...) 测试
-- ============================================================

-- 1. count(distinct 单字段)
select count(distinct a_category) from /test/aaa/test_aggr
/**
output()
match("count(distinct a_category)","3")
**/
;

-- 2. count(distinct 数值字段)
select count(distinct a_int) from /test/aaa/test_aggr
/**
output()
**/
;

-- 3. count(distinct bool 字段)
select count(distinct a_bool) from /test/aaa/test_aggr
/**
output()
match("count(distinct a_bool)","2")
**/
;

-- 4. count(distinct) + where
select count(distinct a_category) from /test/aaa/test_aggr where a_bool=true
/**
output()
**/
;

-- 5. count(distinct) 空结果
select count(distinct a_category) from /test/aaa/test_aggr where a_int=9999
/**
output()
**/
;