I am trying to use an update statement in azure synapse.I want to update a table by joining two tables. Could you help me please. Here is the query, display(spark.sql("UPDATE DimSKUProduct Set YN_NPL = 'Y' from DimSKUProduct inner join DimSKUNpl on DimSKUProduct.SKU_NO = DimSKUNpl.SKU_NO"))
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I need to do a MERGE in Oracle, but I'm stuck.
In SQL Server, I always use the BY SOURCE and BY TARGET condition to check where record exists, and then take an action.
I'm a little confused because I don't know how to achieve the same in PL/SQL.
I need to do a MERGE on two tables (customers and customers_stage).
If the record does not exists in the customer table - then insert.
If the record exits in both - then update.
If the record does not exists in customers_stage - then delete.
In SQL Server, it would look like this:
MERGE INTO dbo.Customers AS target
USING dbo.Customers_stage AS source ON target.ID = source.ExternalID
WHEN NOT MATCHED BY TARGET
THEN
INSERT
WHEN MATCHED
THEN
UPDATE
WHEN NOT MATCHED BY SOURCE
THEN
DELETE
How to achieve the same functionality in Oracle? I use SQL Developer.
Thank you very much.
I have two tables A(i,j,k) and B(m,n).
I want to update the 'm' column of B table by taking sum(j) from table A. Is it possible to do it in Vertica?
Following code can be used for Teradata, but does Vertica have this kind of flexibility?
Update B from (select sum(j) as m from A)a1 set m=a1.m;
The Teradata SQL syntax won't work with Vertica, but the following query should do the same thing :
update B set m = (select sum(j) from A)
Depending on the size of your tables, this may not be an efficient way to update data. Vertical is a WORM (write once read many times) store, and is not optimized for updates or deletes.
An alternate way would be to first temporarily move the data in the target table to another intermediate (but not temporary) table. After that write a join query using the other table to produce the desired result, and finally use export table with that join query. Finally drop the intermediate table. Of course, this is assuming you have partitioned your table in a way suitable for your update logic.
How can we update multiple columns in multiple tables in a single query?
I tried the below but no success.
My tables
update Class c, School s
set c.Status='Absent', s.Status='Absent'
Where c.ID='&ID' and c.ID=s.ID;
Any clues are appreciable.
You can't do a direct update of multiple tables in Oracle.
You might be able to do an update of a view, like this:
update (
select c.status class_status, s.status school_status
from Class c, School s
Where c.ID='&ID' and c.ID=s.ID )
set class_status='Absent', school_status='Absent'
Oracle will only allow this if the join between the tables preserves keys - i.e. each row produced by the join directly maps to a single row in the source table(s) being updated. I suspect that in this case that School is not key-preserved as each row in that table probably relates to more than one row in Class. So you won't be able to do this in a single statement.
Oracle is far less tolerant of fuzzy relational thinking than other systems.
I need a help on SSIS.
I have a table called Orders with millions of records. It have a column called OrderID. This is in SQL Server.
I have a similar table called Orders with again millions of rows and same column called OrderID. This is in Oracle Server
Now I need to pass OrderID from SQL Server and check the OrderID exists in Oracle Server.
I tried Lookup and Merge Join. Both were deadly slow.
Any help on Quickly perform a join if OrderID found then set = Found else NotFound.
Please help me out
Can the UPDATE query be used without a WHERE clause? And if so in what conditions?
if you don't use the WHERE clause all the records on the table will be affected
So, I think when you want to update the whole field for some kind of reasons like updating the status of users enrollment to free for all users.
UPDATE users SET status = "free";
The UPDATE statement in SQL is used to update records in the table. We can modify one or multiple records (rows) in a table using UPDATE statement. If you do not use WHERE clause in UPDATE statement, all the records in the table will be updated.