Convert this datetime from SQL Server to Snowflake - date

Question

I have this piece of code that works in SQL server. I'm having trouble getting it to run in snowflake. 'Datetime' is filetype DateTime in snowflake, but in SQL, it's just a date MM-DD-YYYY, so there is the 6:00 added to turn it into a datetime.
I want the end result to be a date.
Below is SQL Server:
CONVERT(DATE, TEMP.DATETIME - ISNULL((
SELECT CAST(MIN(s_first.FromTimeOfDay) AS DATETIME)
FROM Shift s_first
WHERE s_first.FromDay = s.FromDay
AND s_first.ShiftCalendarID = s.ShiftCalendarID
), CAST('6:00' AS DATETIME))) AS ProductionDate
Here is what I have in Snowflake:
to_date(TEMP.DATETIME) - ifnull(to_date((
SELECT MIN(s_first.FromTimeOfDay)
FROM Shift s_first
WHERE s_first.FromDay = s.FromDay
AND s_first.ShiftCalendarID = s.ShiftCalendarID
), (
SELECT to_date('1900-01-01 06:00:00.000')
))) AS ProductionDate
It's not liking the filetype. I get a filetype error:
invalid type [TO_DATE((SELECT MIN(S_FIRST.FROMTIMEOFDAY) AS "MIN(S_FIRST.FROMTIMEOFDAY)" FROM SHIFT AS S_FIRST WHERE (S_FIRST.FROMDAY = CORRELATION(S.FROMDAY)) AND (S_FIRST.SHIFTCALENDARID = CORRELATION(S.SHIFTCALENDARID))), (SELECT TO_DATE('1900-01-01 06:00:00.000') AS "TO_DATE('1900-01-01 06:00:00.000')" FROM (VALUES (null)) DUAL))] for parameter 'TO_DATE'
Update::
This is the original SQL that i'm trying to write in snowflake.
SELECT
e.Name AS ProductionUnit,
temp.DateTime AS DateTime,
s.Reference AS Shift,
CONVERT(TIME, temp.DateTime) AS Time,
CONVERT(DATE, temp.DateTime - ISNULL((SELECT CAST(MIN(s_first.FromTimeOfDay) AS DateTime) FROM Shift s_first WHERE s_first.FromDay = s.FromDay AND s_first.ShiftCalendarID = s.ShiftCalendarID), CAST('6:00' AS DateTime))) AS ProductionDate,
temp.ScrapReason AS ScrapReason,
temp.Quantity AS ScrapQuantity,
'Manually Registered' AS RegistrationType
FROM (SELECT
CAST(SUM(sreg.ScrapQuantity) AS int) AS Quantity,
sreas.Name As ScrapReason,
DATEADD(MINUTE, 30 * (DATEPART(MINUTE, sreg.ScrapTime) / 30), DATEADD(HOUR, DATEDIFF(HOUR, 0, sreg.ScrapTime), 0)) AS DateTime,
srer.EquipmentID AS EquipmentID
FROM qms.ScrapRegistration sreg WITH (NOLOCK)
INNER JOIN qms.ScrapReason sreas WITH (NOLOCK) ON sreas.ID = sreg.ScrapReasonID
INNER JOIN WorkRequest wr WITH (NOLOCK) ON wr.ID = sreg.WorkRequestID
INNER JOIN SegmentRequirementEquipmentRequirement srer WITH (NOLOCK) ON srer.SegmentRequirementID = wr.SegmentRequirementID
GROUP BY DATEADD(MINUTE, 30 * (DATEPART(MINUTE, sreg.ScrapTime) / 30), DATEADD(HOUR, DATEDIFF(HOUR, 0, sreg.ScrapTime), 0)), srer.EquipmentID, sreas.Name) temp
INNER JOIN Equipment e WITH (NOLOCK) ON e.ID = temp.EquipmentID
INNER JOIN ShiftCalendar sc WITH (NOLOCK) ON sc.ID = dbo.cfn_GetEquipmentShiftCalendarID(e.ID, temp.DateTime)
INNER JOIN Shift s WITH (NOLOCK) ON s.ID = dbo.cfn_GetShiftIDFromDateTime(temp.DateTime, sc.ID)
UNION
SELECT
e.Name AS ProductionUnit,
temp.DateTime AS DateTime,
s.Reference AS Shift,
CONVERT(TIME, temp.DateTime) AS Time,
CONVERT(DATE, temp.DateTime - ISNULL((SELECT CAST(MIN(s_first.FromTimeOfDay) AS DateTime) FROM Shift s_first WHERE s_first.FromDay = s.FromDay AND s_first.ShiftCalendarID = s.ShiftCalendarID), CAST('6:00' AS DateTime))) AS ProductionDate,
temp.ScrapReason AS ScrapReason,
temp.Quantity AS ScrapQuantity,
'Auto Registered' AS RegistrationType
FROM (SELECT
SUM(ISNULL(asr.ScrapQuantity, 0)) AS Quantity,
sreas.Name As ScrapReason,
DATEADD(MINUTE, 30 * (DATEPART(MINUTE, asr.ScrapTime) / 30), DATEADD(HOUR, DATEDIFF(HOUR, 0, asr.ScrapTime), 0)) AS DateTime,
srer.EquipmentID AS EquipmentID
FROM proj.AutoScrapRegistration asr WITH (NOLOCK)
INNER JOIN qms.ScrapReason sreas WITH (NOLOCK) ON sreas.ID = asr.ScrapReasonID
INNER JOIN WorkRequest wr WITH (NOLOCK) ON wr.ID = asr.WorkRequestID
INNER JOIN SegmentRequirementEquipmentRequirement srer WITH (NOLOCK) ON srer.SegmentRequirementID = wr.SegmentRequirementID
GROUP BY DATEADD(MINUTE, 30 * (DATEPART(MINUTE, asr.ScrapTime) / 30), DATEADD(HOUR, DATEDIFF(HOUR, 0, asr.ScrapTime), 0)), srer.EquipmentID, sreas.Name) temp
INNER JOIN Equipment e WITH (NOLOCK) ON e.ID = temp.EquipmentID
INNER JOIN ShiftCalendar sc WITH (NOLOCK) ON sc.ID = dbo.cfn_GetEquipmentShiftCalendarID(temp.EquipmentID, temp.DateTime)
INNER JOIN Shift s WITH (NOLOCK) ON s.ID = dbo.cfn_GetShiftIDFromDateTime(temp.DateTime, sc.ID)

Answer 1

So the first step is to make up some T-SQL data that to help understand hwo the old can ran.
So taking the inner most step on the original sql:
with Shift as (
select * from (values
(1, '2020-11-03', '06:30' )
) as t(ShiftCalendarID, fromday, FromTimeOfDay)
)
SELECT CAST(MIN(s_first.FromTimeOfDay) AS DATETIME) as sub
FROM Shift s_first;
we get:
sub
1900-01-01 06:30:00.000
so we can then weave temp and s together into this CTE data:
with Shift as (
select * from (
values
(1, '2020-11-03', '06:30' )
) as t(ShiftCalendarID, fromday, FromTimeOfDay)
), temp as (
select
t.ShiftCalendarID,
t.FromDay,
CAST(t.date_time AS DATETIME) as date_time
from (
values
(1, '2020-11-03', '2020-11-03 07:41:12' ),
(1, '2020-11-03', '2020-11-03 05:41:12' )
) as t(ShiftCalendarID, FromDay, date_time )
)
and run your existing sql:
select t.*
,CONVERT(DATE, t.date_time - ISNULL((
SELECT CAST(MIN(s_first.FromTimeOfDay) AS DATETIME)
FROM Shift s_first
WHERE s_first.FromDay = t.FromDay
AND s_first.ShiftCalendarID = t.ShiftCalendarID
), CAST('6:00' AS DATETIME))) AS ProductionDate
from temp as t;
which gives:
ShiftCalendarID
FromDay
date_time
ProductionDate
1
2020-11-03
2020-11-03 07:41:12.000
2020-11-03
1
2020-11-03
2020-11-03 05:41:12.000
2020-11-02
there is a subtraction of a time component from a datetime, if the min is not present a default of 6am is used.
And this code looks very much like it's a correlated subquery, so that will have it's own issues, but using the above fake data in snowflake:
so the data CTE's:
with Shift as (
select * from values
(1, '2020-11-03', '06:30' )
t(ShiftCalendarID, fromday, FromTimeOfDay)
), temp as (
select
t.ShiftCalendarID,
t.FromDay,
t.date_time::timestamp as date_time
from values
(1, '2020-11-03', '2020-11-03 07:41:12' ),
(1, '2020-11-03', '2020-11-03 05:41:12' ),
(2, '2020-11-03', '2020-11-03 05:41:12' )
t(ShiftCalendarID, FromDay, date_time )
)
and an extra help CTE to resolve the correlated subquery:
, min_times as (
select
ShiftCalendarID,
fromday,
MIN(FromTimeOfDay) as FromTimeOfDay
from Shift
group by 1,2
)
and then this expanded SQL to see all the steps:
select t.*
,nvl(mt.FromTimeOfDay::time, '06:00'::time) as sub_time
,dateadd('hour', -hour(sub_time), t.date_time) as da1
,dateadd('minute', -minute(sub_time), da1) as da2
,da2::date as ProductionDate
from temp as t
left join min_times as mt
on t.ShiftCalendarID = mt.ShiftCalendarID
and t.FromDay = mt.FromDay
gives:
SHIFTCALENDARID
FROMDAY
DATE_TIME
SUB_TIME
DA1
DA2
PRODUCTIONDATE
1
2020-11-03
2020-11-03 07:41:12.000
06:30:00
2020-11-03 01:41:12.000
2020-11-03 01:11:12.000
2020-11-03
1
2020-11-03
2020-11-03 05:41:12.000
06:30:00
2020-11-02 23:41:12.000
2020-11-02 23:11:12.000
2020-11-02
2
2020-11-03
2020-11-03 05:41:12.000
06:00:00
2020-11-02 23:41:12.000
2020-11-02 23:41:12.000
2020-11-02
so that can then be compacted (perhaps too far)..
select t.*
,dateadd('minute', -minute(nvl(mt.FromTimeOfDay::time, '06:00'::time)), dateadd('hour', -hour(nvl(mt.FromTimeOfDay::time, '06:00'::time)), t.date_time))::date as ProductionDate
from temp as t
left join min_times as mt
on t.ShiftCalendarID = mt.ShiftCalendarID
and t.FromDay = mt.FromDay
less compacted:
select ShiftCalendarID, FROMDAY, ProductionDate
from (
select t.ShiftCalendarID
,t.FROMDAY
,nvl(mt.FromTimeOfDay::time, '06:00'::time) as sub_time
,dateadd('hour', -hour(sub_time), t.date_time) as da1
,dateadd('minute', -minute(sub_time), da1) as da2
,da2::date as ProductionDate
from temp as t
left join min_times as mt
on t.ShiftCalendarID = mt.ShiftCalendarID
and t.FromDay = mt.FromDay
)
SHIFTCALENDARID
FROMDAY
PRODUCTIONDATE
1
2020-11-03
2020-11-03
1
2020-11-03
2020-11-02
2
2020-11-03
2020-11-02