compare 2 tables if match update if not match insert - sql-server

I have 2 tables with same table structure. Table A is having all transaction with 3 unique key in each record. Table B have only condition base record only.
I want compare both tables if Table B has matching record than I want to update and Table B have not matching record than insert in Table B.
Can you please suggest best way to do it like ssis or any thing else

The easiest way is a MERGE statement:
MERGE INTO Table_B
USING Table_A
ON TableA.ID1 = Table_B.ID1 AND TableA.ID2 = Table_B.ID2 AND TableA.ID3 = Table_B.ID3
WHEN MATCHED THEN UPDATE SET A = Table_A.A, B = Table_A.B -- Etcetera...
WHEN NOT MATCHED THEN INSERT (A, B) VALUES (Table_A.a, Table_A.B) -- Etcetera...
WHEN NOT MATCHED BY SOURCE THEN DELETE -- If Necessary...
;
By the way, don't forget the ";" at the end. SQL Server doesn't usually need them, but a MERGE does.

Related

Efficiently inserting non-duplicate variations of rows into the same table (EXCEPT / NOT EXISTS?)

I have a process which generates a number of potentially asymmetric outcomes (record A links to record B, but record B may not link to record A). Each of these outcomes are stored in a table and I want to insert into that same table all the missing links (i.e. generate a row for every case where record B links to record A) - without generating duplicates.
From looking around it seems that NOT EXISTS is the preferred method for this. But as this is an INSERT into the same table, I wanted to see if anyone had ideas for a more efficient approach (table size will vary from ~50,000 to ~20,000,000).
INSERT INTO [table1]
([record_id], [linked_record_id], [flag_value])
SELECT
,[linked_record_id] AS [record_id]
,[record_id] AS [linked_record_id]
,[flag_value]
FROM [table1] AS A
WHERE [flag_value] = 1
AND NOT EXISTS (
SELECT
[record_id]
,[linked_record_id]
,[flag_value]
FROM [table1] AS B
WHERE [flag_value] = 1
AND A.[linked_record_id] = B.[record_id]
)

Merge not working when using condtion of rowid in oracle

I have a person table as:
I have another table temp_person
I want to merge the data of temp_person to person table when their rowid matches.So,I tried:
MERGE INTO OT.person A
USING OT.TEMP_person B
ON (A.rowid=B.rowid)
WHEN MATCHED THEN
UPDATE SET A.age=B.age
But it says:
0 rows merged.
Why are the rows not being merged?

Insert New Records Into Table Using If/Else Statement

I have two SQL Server tables where I need to add records from one table to the next. If the unique identifier already exists in the target table, then update the record to the data coming from source table - If the unique identifier doesn't exist, then insert the entire new record into the target table.
I seem to have gotten the initial part to work where I update the records in target table but the the part where I would INSERT new records does not seem to be working.
if exists (
select 1
from SCM_Top_Up_Operational O
join SCM_Top_Up_Rolling R ON O.String = R.string
)
begin
update O
set O.Date_Added = R.Date_Added,
O.Real_Exfact = R.Real_Exfact,
O.Excess_Top_Up = R.Excess_Top_Up
from SCM_Top_Up_Operational O
join SCM_Top_Up_Rolling R on O.String = R.String
where O.String = R.string and R.date_added > O.date_added
end
else
begin
insert into SCM_Top_Up_Operational (String,Date_Added,Real_Exfact,Article_ID,Excess_Top_Up,Plant)
select String,Date_Added,Real_Exfact,Article_ID,Excess_Top_Up,Plant
from SCM_Top_Up_Rolling
end
If I followed you correctly, you should be able to solve this with a single SQL query, using SQL Server MERGE syntax, available since SQL Server 2008.
From the documentation:
Runs insert, update, or delete operations on a target table from the results of a join with a source table. For example, synchronize two tables by inserting, updating, or deleting rows in one table based on differences found in the other table.
Consider the following query:
MERGE
SCM_Top_Up_Operational O
USING SCM_Top_Up_Rolling R ON (O.String = R.string)
WHEN MATCHED
THEN UPDATE SET
O.Date_Added = R.Date_Added,
O.Real_Exfact = R.Real_Exfact,
O.Excess_Top_Up = R.Excess_Top_Up
WHEN NOT MATCHED BY TARGET
THEN INSERT ( String, Date_Added, Real_Exfact, Article_ID, Excess_Top_Up, Plant)
VALUES (R.String, R.Date_Added, R.Real_Exfact, R.Article_ID, R.Excess_Top_Up, R.Plant)

TSQL - Copy data from one table to another

I'm copying the contents of a table into another identical table. But there are already data in the destination table.
Some data in the destination table has the same code as the source table.
Is it possible to skip the duplicates and not to block the insertion for the rest of the data without it failing?
insert into [DB2].[dbo].[MAN] values([MAN],[DES])
SELECT [MAN]
,[DES]
FROM [DB1].[dbo].[MAN]
You can use NOT EXISTS :
INSERT INTO [DB2].[dbo].[MAN] ([MAN], [DES])
SELECT M.[MAN], M.[DES]
FROM [DB1].[dbo].[MAN] AS M
WHERE NOT EXISTS (SELECT 1 FROM [DB2].[dbo].[MAN] M1 WHERE M1.COL = M.COL);
You need to change the M1.COL = M.COL with your actual column name from which you can identify the duplicate values.
If you have your unique col then you can go like this.
insert into [DB2].[dbo].[MAN] values([MAN],[DES])
SELECT [MAN]
,[DES]
FROM [DB1].[dbo].[MAN] WHERE uniqueCol NOT IN (SELECT uniqueCol FROM [DB2].[dbo].[MAN])
Otherwise append few columns to get unique one and compare like that.

delete duplicate rows

anyone know how can i delete duplicate rows by writing new way from script below to improve performance.
DELETE lt1 FROM #listingsTemp lt1, #listingsTemp lt2
WHERE lt1.code = lt2.code and lt1.classification_id > lt2.classification_id and (lt1.fap < lt2.fap or lt1.fap = lt2.fap)
Delete Duplicate Rows in a SQL Table :
delete table_a
where rowid not in
(select min(rowid) from table_a
group by column1, column2);
1 - Create an Identity Column (ID) for your table (t1)
2 - Do a Group by on your table with your conditions and get IDs of duplicated records.
3 - Now, simply Delete records from t1 where IDs IN duplicated IDs set.
Look into BINARY_CHECKSUM .... you could possibly use it when creating your temp tables to more quickly determine if the data is the same.... for example create a new field in both temp tables storing the binary_checksum value... then just delete where those fields equal
The odiseh answer seems to be valid (+1), but if for some reason you can't alter the structure of the table (because you have not the code of the applications that are using it or something) you could write a job that run every night and delete the duplicates (using the Moayad Mardini code).

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