SQL join with previous row from the same group - sql

Question

I have a problem with sql query. I'm trying to create one time script which will put data to table. I have temporary table of new values ordered by date and i'm going to search previous value which have to have the same GroupId, TransactionId and FieldTypeId but ClaimModificationId have to be smaller.
Below i write a script which would be good if not error throwing on line:
where m2.ClaimModificationId < m1.ClaimModificationId
sql does not allow do referer to m1 table. Is there a method to write that condition differently?
create table #modifications (
[ClaimModificationId] INT IDENTITY(1,1),
[GroupId] INT,
[FieldTypeId] INT,
[FieldName] NVARCHAR(255),
[TransactionId] INT,
[NewValue] NVARCHAR(255),
[UserEmail] NVARCHAR(255),
[ModificationDate] DATETIME,
[Action] NVARCHAR(50))
select top 10
m1.[GroupId],
m1.[FieldTypeId],
m1.[FieldName],
m1.[TransactionId],
cm4.[NewValue] as OldValue,
m1.[NewValue],
m1.[UserEmail],
m1.[ModificationDate],
m1.[Action]
from #modifications m1
left join (
select max(m2.ClaimModificationId) as ClaimModificationId, m2.[GroupId], m2.[FieldTypeId], m2.TransactionId
from #modifications m2
where m2.ClaimModificationId < m1.ClaimModificationId
group by m2.GroupId, m2.FieldTypeId, m2.TransactionId) m3
on m3.groupId = m1.GroupId and m3.FieldTypeId = m1.FieldTypeId and m3.TransactionId = m1.TransactionId
LEFT JOIN #modifications cm4 ON m3.ClaimModificationId = cm4.ClaimModificationId

Answer 1

Try with OUTER APPLY:
SELECT TOP 10
m1.[GroupId] ,
m1.[FieldTypeId] ,
m1.[FieldName] ,
m1.[TransactionId] ,
cm4.[NewValue] AS OldValue ,
m1.[NewValue] ,
m1.[UserEmail] ,
m1.[ModificationDate] ,
m1.[Action]
FROM #modifications m1
OUTER APPLY ( SELECT MAX(m2.ClaimModificationId) AS ClaimModificationId ,
m2.[GroupId] ,
m2.[FieldTypeId] ,
m2.TransactionId
FROM #modifications m2
WHERE m2.ClaimModificationId < m1.ClaimModificationId
AND m2.groupId = m1.GroupId
AND m2.FieldTypeId = m1.FieldTypeId
AND m2.TransactionId = m1.TransactionId
GROUP BY m2.GroupId ,
m2.FieldTypeId ,
m2.TransactionId
) m3
LEFT JOIN #modifications cm4 ON m3.ClaimModificationId = cm4.ClaimModificationId

Answer 2

you can try something like this
create table #modifications
(
[ClaimModificationId] INT IDENTITY(1,1),
[GroupId] INT,
[FieldTypeId] INT,
[FieldName] NVARCHAR(255),
[TransactionId] INT,
[NewValue] NVARCHAR(255),
[UserEmail] NVARCHAR(255),
[ModificationDate] DATETIME,
[Action] NVARCHAR(50)
)
INSERT INTO #modifications values(1,1,'field',2,'new val1','email#email.com',GETDATE(),'inserted')
INSERT INTO #modifications values(1,2,'field',2,'val1','email#email.com',GETDATE(),'inserted')
INSERT INTO #modifications values(2,1,'field',3,'val2','email#email.com',GETDATE(),'inserted')
INSERT INTO #modifications values(1,1,'field',2,'val3','email#email.com',GETDATE(),'inserted')
INSERT INTO #modifications values(1,1,'field',2,'val4','email#email.com',GETDATE(),'inserted')
INSERT INTO #modifications values(1,1,'field',2,'val5','email#email.com',GETDATE(),'inserted')
INSERT INTO #modifications values(2,1,'field',3,'val5','email#email.com',GETDATE(),'inserted')
SELECT TOP 10
m1.[GroupId],
m1.[FieldTypeId],
m1.[FieldName],
m1.[TransactionId],
LAG([NewValue]) OVER(PARTITION by GroupId, FieldTypeId, TransactionId ORDER BY ClaimModificationId ASC) as OldValue,
m1.[NewValue],
m1.[UserEmail],
m1.[ModificationDate],
m1.[Action]
from #modifications m1