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【DM版本】:DM8
【操作系统】：LINUX
【CPU】:
【问题描述】*：
表1：
CREATE TABLE "WATER_DATA"."TR_UNDERWATER_STATION_INFO"
(
"mnName" VARCHAR(100),
"mn" VARCHAR(20),
"stName" VARCHAR(100),
"st" VARCHAR(10),
"createTime" DATETIME(6),
)；
表2：
CREATE TABLE WATER_DATA.TR_UNDERWATER_STATION_LEVEL_DATA
(
"waterName" VARCHAR(50),
"mnNo" VARCHAR(20),
"waterLevel" NUMBER(10,0),
"dataTime" DATETIME(6),
"LIST" VARCHAR(20000)) ；

SQL1: select
distinct mnno
from WATER_DATA.TR_UNDERWATER_STATION_LEVEL_DATA
where dataTime > DATE_ADD(GETDATE(),INTERVAL '-2' day) order by mnno

SQL2: select mn from WATER_DATA.TR_UNDERWATER_STATION_INFO where STATION_SOURCE_TYPE = '01' order by mn

SQL3: select
count(*)
from (
select
distinct mnno
from WATER_DATA.TR_UNDERWATER_STATION_LEVEL_DATA
where dataTime > DATE_ADD(GETDATE(),INTERVAL '-2' day) order by mnno) a
where a.mnNo in (
select mn from WATER_DATA.TR_UNDERWATER_STATION_INFO where STATION_SOURCE_TYPE = '01' order by mn);

SQL4: select count(distinct mnno) from WATER_DATA.TR_UNDERWATER_STATION_LEVEL_DATA
where
dataTime > DATE_ADD(GETDATE(),INTERVAL '-2' day)
and mnNo in (
select mn from WATER_DATA.TR_UNDERWATER_STATION_INFO where STATION_SOURCE_TYPE = '01');

SQL5: select count(distinct mnno) from WATER_DATA.TR_UNDERWATER_STATION_LEVEL_DATA
where
dataTime > DATE_ADD(GETDATE(),INTERVAL '-6' MONTH)
and mnNo in (
select mn from WATER_DATA.TR_UNDERWATER_STATION_INFO where STATION_SOURCE_TYPE = '01');

问题1：SQL1和SQL2的查询结果集编码相同的有19个，但是SQL3查询出来的数量为0；
问题2：SQL4查询出来的数量是23，实际应该是19。
问题3：SQL5查询出来的结果是0，实际应该是23