I am using SQL Server 2012 and have two tables with identical structure. I want to insert new records from table 1 to table 2 if they don't already exist in table 2.
If they already exist, I want to update all of the existing records in table 2.
There are some 30 columns in my tables and I want to update all of them.
Can someone please help with this? I had a look at various links posted over internet, but quite don't understand how my statement should look like.
It's really not that hard....
You need:
a source table (or query) to provide data
a target table to merge it into
a condition on which those two tables are checked
a statement what to do if a match (on that condition) is found
a statement what to do if NO match (on that condition) is found
So basically, it's something like:
-- this is your TARGET table - this is where the data goes into
MERGE dbo.SomeTable AS target
-- this is your SOURCE table where the data comes from
USING dbo.AnotherTable AS source
-- this is the CONDITION they have to "meet" on
ON (target.SomeColumn = source.AnotherColumn)
-- if there's a match, so if that row already exists in the target table,
-- then just UPDATE whatever columns in the existing row you want to update
WHEN MATCHED THEN
UPDATE SET Name = source.Name,
OtherCol = source.SomeCol
-- if there's NO match, that is the row in the SOURCE does *NOT* exist in the TARGET yet,
-- then typically INSERT the new row with whichever columns you're interested in
WHEN NOT MATCHED THEN
INSERT (Col1, Col2, ...., ColN)
VALUES (source.Val1, source.Val2, ...., source.ValN);
Related
We'd like to set the IS_DEL bit = 1 when a record exists in a Target table that doesn't exist in the Source table.
Is it possible to use a MERGE statement using the WHEN NOT MATCHED clause, but make it perform an UPDATE?
When attempting to do so, I'm getting a "ORA-00905: missing keyword" message.
MERGE
INTO AMEPSA.ENTERPRISE_LOCATION trg
USING (
SELECT C.LOCATION_KEY as LOCATION_KEY
FROM AMEPSA.ENTERPRISE_LOCATION C
INNER JOIN AMESTAGE.VW_LOCATION L ON C.REC_SRC_KEY_CD = L.LOCATION_ID
WHERE C.CURR_REC_IND = 'Y'
) src
ON (trg.LOCATION_KEY = src.LOCATION_KEY)
WHEN NOT MATCHED THEN UPDATE
SET trg.IS_DEL = 1
Does the "WHEN NOT MATCH" clause only support "THEN INSERT"?
From the documentation:
Use the MERGE statement to select rows from one or more sources for update or insertion into a table or view. You can specify conditions to determine whether to update or insert into the target table or view.
The syntax looks for rows in the source table (src) which do or do not have matching rows in the target table (trg). If there is a matching target row then it updates that; if there is not a matching row then it inserts a new row in the target table.
It does not, and cannot, look for rows in the target table that are not matched in the source table - which is what you are trying to identify and update.
The syntax diagrams for WHEN MATCHED and WHEN NOT MATCHED also make it clear that you cannot do WHEN NOT MATCHED THEN UPDATE.
Yes you can only insert when not match. See exact options in oracle merge.
The condition can refer to either the data source or the target table. If the condition is not true, then the database skips the update operation when merging the row into the table.
I'm having trouble getting this compound insert to work in my MERGE statement between two tables (Ignore the when match condition, I know its bad practice). The issue I'm having is getting the ServerId field in the target table to fill. The Team field is filling fine but all of the rows have a null value for ServerId. I can't find an example online for this so I'm hoping someone can help. I don't seem to have any syntactical errors and I know the column 'ServerName' in the Source table is filled for all rows.
MERGE ApplicationTeams AS Target
USING TempApplicationTeams AS Source
ON (Target.ServerId = (SELECT ID from Servers WHERE Name='Source.ServerName') AND Target.Team = Source.Team)
WHEN MATCHED THEN
UPDATE SET Target.Team = Target.Team
WHEN NOT MATCHED BY TARGET THEN
INSERT (ServerId, Team) VALUES((SELECT ID from Servers WHERE Name='Source.ServerName'), Source.Team)
WHEN NOT MATCHED BY SOURCE THEN
DELETE
;
Thanks.
I think you should remove the single quoutes on the where clausule.
You wrote:
(SELECT ID from Servers WHERE Name='Source.ServerName')
But I think you should write this:
(SELECT ID from Servers WHERE Name=Source.ServerName)
And make sure the select id returns only one row otherwise the statement will fail
I hope it will be usefully
This may be a simple query to some of you. But I am not strong in Sql, so expecting some solution for my problem.
I have 2 tables, ProductVenueImport and SupplierVenueImport.
We are dumping all the records from SupplierVenueImport to ProductVenueImport using MERGE clause and a Temp table. Temp will have valid records from SupplerVenuImport and from Temp table we are importing records to ProductVenueImport.
But before importing data to ProductVenueImport from Temp table I need to check for the duplicate records in my target (ProductVenueImport).
For example if I am importing a record with name as 'A', I need to look into ProductVenueImport whether 'A' already existing or not. If it is not existing then only I need to insert 'A' otherwise not.
Could somebody tell me how to do this?
Is using Cursors only the option?
Thanks,
Naresh
Assuming the Temp table itself doesn't have duplicates, you could use MERGE like this:
Insert non-existing products.
Do a NO-OP in case of an existing product.
Use $action in the OUTPUT clause to mark which rows were considered for insertion (and inserted) and which for update (but not really updated).
This is what I mean:
DECLARE #noop int; -- needed for the NO-OP below
MERGE INTO ProductVenueImport AS tgt
USING Temp AS src
ON src.ProductID = tgt.ProdutID
WHEN NOT MATCHED THEN
INSERT ( column1, column2, ...)
VALUES (src.column1, src.column2, ...)
WHEN MATCHED THEN
UPDATE SET #noop = #noop -- the NO-OP instead of update
OUTPUT $action, src.column1, src.column2, ...
INTO anotherTempTable
;
I think this would do this :
INSERT INTO PRODUCTTBL(FEILD1, FIELD2, FIELD3, FIELD4, FIELD5)
SELECT (FIELD1,FIELD2,FIELD3,FIELD4,FIELD5) FROM TEMP WHERE CRITERIAFIELD NOT IN(SELECT DISTINCT CRITERIAFIELD FROM PRODUCTTBL)
This should allow you to check for duplicates in a table
select columnname from tablename
group by columnname
having count(columnname) >1
sorry if I am not getting the question right, can't you use the merge statement on the source table with "When not matched Insert" to insert the new records alone
so in your case it should be like this
merge into ProductVenueImport using temp on (<condition for duplicate>)
when not matched then insert <clause>;
the merge clause will make sure that no duplicate records are inserted into your source table.
I’ve been tasked to synchronize 2 tables (both are identical). They have 60 columns each. Table A is the primary table that will be initially filled. I need to create a stored procedure (done) that will merge these 2 tables and populate both with the same exact data (Update, insert, delete) when called. How would I use the MERGE function in SQL to achieve this? I’ve looked at both the MSDN documentation and similar that’s on technet, but I’m pretty confused on getting started. Do I need to specify each field I need merged? Or is it a simple call I’m missing that will perform this action?
Here is a link to a simple example of the MERGE statement:
http://www.simple-talk.com/sql/learn-sql-server/the-merge-statement-in-sql-server-2008/
The basic syntax reads as:
MERGE table1
USING table2
ON table1.id = table2.id
WHEN MATCHED THEN
--Do an update here
WHEN NOT MATCHED BY TARGET THEN
--Do an insert here (or a delete)
;
You can also use WHEN NOT MATCHED BY SOURCE
Over 60 columns is a great number! When I need to sync 2 identical table I do:
;WITH tbl_to_synch as (
-- Prepare table to update,
Select *,chk = CHECKSUM(*) from [dbo].[tableA]
)
MERGE tbl_to_synch as [Target]
USING (Select *,chk = CHECKSUM(*) from [dbo].[tableB]) as [source]
ON [Target].key = [source].key
WHEN MATCHED AND [Target].chk <> [source].chk THEN
-- UPDATE ONLY row that is changed
UPDATE
SET
column01 = [source].[column01]
,column02 = [source].[column01]
-- ....
,column59 = [source].[column59]
,column60 = [source].[column59]
WHEN NOT MATCHED BY TARGET THEN
insert (column01, column02, ...,column59,column60)
values (column01, column02, ...,column59,column60)
WHEN NOT MATCHED BY SOURCE THEN DELETE
-- Show what is changed
OUTPUT $action, ISNULL(INSERTED.key,DELETED.key);
I have a scenario where i need to synchronize two tables in SSIS
Table A is in DATABASE A and TABLE B is in DATABASE B. Both tables have same schema. I need to have a SSIS package that Synchronize TABLE A with TABLE B in Such a way That
1. It inserts all the records That Exist in Table A into Table B
AND
2. Update TABLE B if Same "Key" exsit in Both but Updated records in Table A
For Example Table A and B both Contains Key = 123 both Few Columns in Table A has been Updated.
I am thinking about using Merge Joins but that helps with only insertion of New records. How i can manage to implement UPDATE thing as well
1.It inserts all the records That Exist in Table A into Table B
Use a lookup transformation .Source will be Table A and Lookup will be Table B .Map the common columns in both the table and select those columns which you need for insertion.After lookup use OLEDB destination and the map the columns coming from the lookup and insert it into Table B
2.Update TABLE B if Same "Key" exsit in Both but Updated records in Table A
Same logic as above .Use lookup and instead of OLEDB Destination use OLEDB Command and then write the update sql .
Update TableB
Set col1=?,col2=?....
In the column mapping map the columns coming out of the lookup
Check out this article
Checking to see if a record exists and if so update else insert
Using Merge :
MERGE TableB b
USING TableA a
ON b.Key = a.Key
WHEN MATCHED AND b.Col1<>a.Col1 THEN
UPDATE
SET b.Col1 = a.Col1
WHEN NOT MATCHED BY TARGET THEN
INSERT (Col1, Col2, col3)
VALUES (a.Col1, a.Col2,a.Col3);
You can execute the Merge SQL in Execute SQL Task in Control Flow
Update : The Lookup transformation tries to perform an equi-join between values in the transformation input and values in the reference dataset.
You can just need to have one Data Flow Task .
Diagram
When the target table data does not have a matching value in the source table then lookup will redirect the target rows to the oledb destination which inserts the Data into source table( Lookup No Match Output)
When the target table rows matches for the business key with the source table then matched rows will be sent to the Oledb Command and using the Update SQL ,the all the target rows from the lookup will be updated in the source table .
This is just an overview .There is a problem with the above design as when the rows matches irrespective of any change in the columns the source table will be updated .So kindly refer the above article or try for search for SCD component in ssis
Update 2:
MERGE TableB b
USING TableA a
ON b.Key = a.Key
WHEN MATCHED THEN
UPDATE
SET b.Col1 = a.Col1
WHEN NOT MATCHED BY TARGET AND a.IsReady=1 THEN --isReady bit data type
INSERT (Col1, Col2, col3)
VALUES (a.Col1, a.Col2,a.Col3);