markdown
```
--原始欄位:
--民國年數字date_number,時間數字time_number
--(ex:971201,6)
--將民國數字轉西元字串
select cast(970101+19110000 as varchar(8)) --output:20080101
--將西元字串轉YYYY-MM-DD字串
select SUBSTRING(cast(970101+19110000 as varchar(8)),1,4)+'-'
+SUBSTRING(cast(970101+19110000 as varchar(8)),5,2)+'-'
+SUBSTRING(cast(970101+19110000 as varchar(8)),7,2) --output:2008-01-01
--將時分數字PAD成時分秒,在零點時可能只有個位數 如 00:06 =6
select REPLACE(STR(cast(6 as varchar(6)), 6), SPACE(1), '0') --output:000006
--將補齊的時分秒轉為HH:MM:SS字串
select substring(REPLACE(STR(cast(6 as varchar(6)), 6), SPACE(1), '0') ,1,2)+':'
+substring(REPLACE(STR(cast(6 as varchar(6)), 6), SPACE(1), '0') ,3,2)+':'
+substring(REPLACE(STR(cast(6 as varchar(6)), 6), SPACE(1), '0') ,5,2) --output:00:00:06
--將時間字串與時分秒字串轉為DATETIME
select convert(datetime,
SUBSTRING(cast(970101+19110000 as varchar(8)),1,4)+'-'
+SUBSTRING(cast(970101+19110000 as varchar(8)),5,2)+'-'
+SUBSTRING(cast(970101+19110000 as varchar(8)),7,2)
+' '
+substring(REPLACE(STR(cast(6 as varchar(6)), 6), SPACE(1), '0') ,1,2)+':'
+substring(REPLACE(STR(cast(6 as varchar(6)), 6), SPACE(1), '0') ,3,2)+':'
+substring(REPLACE(STR(cast(6 as varchar(6)), 6), SPACE(1), '0') ,5,2)
,121) --output:2008-01-01 00:00:06.000
```