I am trying to create an update statement in Oracle.
Here it is version in SQL Server:
UPDATE ev
SET
(ev.station_type = t.st_type, ev.adt = t.adt )
FROM source ev
JOIN dataTbl t
ON ev.counterID = t.counterID
There are two tables
source table were counterID is primary key
dataTBL table were counterID is Foreign key
I am tring to get data from dataTBL to souce table.
I would appreciate if someone helps to create an Oracle version of the update.
Thanks,
Greener
You want to use this technique:
UPDATE ( SELECT ev.station_type
, t.st_type
, ev.adt ev_adt
, t.adt t_adt
FROM source ev
JOIN dataTbl t
ON ev.counterID = t.counterID
)
SET station_type = st_type
, ev_adt = t_adt
;
The subquery creates your resultset, at which point you can use the SET clause to update the columns however you wish.
I believe the following syntax would work (no Oracle at hand to check):
UPDATE ev
SET (station_type, adt ) = (
SELECT (t.st_type, t.adt)
FROM dataTbl t
WHERE t.counterId = ev.counterId
)
WHERE ev.counterId IN (SELECT t.counterID FROM t);
Edit: the WHERE clause repetition looks ugly, but as #Steve points out it's needed to avoid inserting nulls in rows that have no matching entry in dataTbl (if that's a possibility in your use case, of course). If you do need such precautions, #Steve's join-based solution may be preferable.
Related
I'm converting ETL queries written for Netezza to RedShift. I'm facing some issues with ROWID, because it's not supported in RedShift. I have tried using the key columns in the predicates, based on which ROWID is being generated to actually do a workaround. But i'm confused which columns would be used if there are multiple join operations. So is there anyone who can help me convert the query. I even tried to use ROW_NUMBER() over () function, but it also doesn't work because row ids won't be unique for all rows.
Here are the queries from netezza:
Query #1
CREATE TEMP TABLE TMPRY_DELTA_UPD_1000 AS
SELECT
nvl(PT.HOST_CRRNCY_SRRGT_KEY,-1) as HOST_CRRNCY_SRRGT_KEY,
delta1.ROWID ROW_ID
FROM TMPRY_POS_TX_1000 PT
LEFT JOIN TMPRY_TX_CSTMR_1000 TC ON PT.TX_SRRGT_KEY = TC.TX_SRRGT_KEY AND PT.UPDT_TMSTMP > '2017-01-01'
AND PT.INS_TMSTMP < '2017-01-01' AND PT.DVSN_NBR = 70
JOIN INS_EDW_CP.DM_TX_LINE_FCT delta1 ON PT.TX_SRRGT_KEY = delta1.TX_SRRGT_KEY
WHERE
(
delta1.HOST_CRRNCY_SRRGT_KEY <> PT.HOST_CRRNCY_SRRGT_KEY OR
)
AND PT.DVSN_NBR = 70;
Query #2
UPDATE INS_EDW_CP..DM_TX_LINE_FCT base
SET
base.HOST_CRRNCY_SRRGT_KEY = delta1.HOST_CRRNCY_SRRGT_KEY,
)
FROM TMPRY_DELTA_UPD_1000 delta1
WHERE base.ROWID = delta1.ROW_ID;
How can i convert query # 2?
Well, most of the time I have seen joins on rowid it is due to performance optimizations, but in some cases there ARE no unique combination of columns in the table.
Please talk to the people owning these data & run your own analysis of different key combinations and then get back to us.
The Problem
I need to write an Update query where my SET references an outer joined table.
I can do this fairly easily with SQL Server but I'm having a heck of a time figuring out the syntax in Oracle as I'm only allow a single table in an update query.
I have written the following Oracle query:
UPDATE SalesExt_tmp tmp
SET slsrep = (SELECT three_dig_rep
FROM dw_sls_rep_conv sls
WHERE sls.aims_rep = tmp.slsrep)
WHERE EXISTS (SELECT three_dig_rep
FROM dw_sls_rep_conv sls
WHERE sls.aims_rep = tmp.slsrep)
AND tmp.sysind = 'AIM';
This takes care of the intersection but I need to deal with values in SalesExt_tmp that do not have equivalent matches in dw_sls_rep_conv (I plan to add a case statement to set null values to a default value). To do this I need to set up dw_sls_rep_conv as an outer joined table. But this is where I get stuck.
SQL Server Example
In SQL Server the solution is a piece of cake as you can have multiple tables in an Update Query:
UPDATE SalesExt_tmp tmp
LEFT JOIN dw_sls_rep_conv sls ON sls.aims_rep = tmp.slsrep
SET tmp.slsrep = sls.three_dig_rep
WHERE tmp.sysind = 'AIM';
But I can't for the life of me figure out how to do this in Oracle. I understand that this query will allow my slsrep field to be set to NULL in some occasions which causes me to fear that this operation may not be allowed.
Questions
1) Firstly is this possible in Oracle? (It's got to be, right?)
2) How do I need to restructure my query to pull this off? I'm guessing my WHERE EXISTS clause needs to go... but I'm still stuck as to where to place my JOIN.
If I understood you correctly, you want to set the value to NULL if there is no match in the dw_sls_rep_conv table? If so, just drop your EXISTS condition and all the rows will be updated:
UPDATE SalesExt_tmp tmp
SET slsrep = (SELECT three_dig_rep
FROM dw_sls_rep_conv sls
WHERE sls.aims_rep = tmp.slsrep)
WHERE tmp.sysind = 'AIM';
If there is a match in the dw_sls_rep_conv table, then the slsrep column will be updated with selected value, otherwise, with NULL.
Have you considered using a subquery in your where clause that performs the outer join as you stated like this:
UPDATE SalesExt_tmp tmp
SET slsrep = (SELECT three_dig_rep
FROM dw_sls_rep_conv sls WHERE sls.aims_rep = tmp.slsrep)
WHERE
tmp.rowid in
(SELECT tmp1.rowid
FROM SalesExt_tmp tmp1,
dw_sls_rep_conv sls
WHERE
tmp1.slsrep = sls.aims_rep (+)
AND tmp1.sysind = 'AIM' );
I have two tables #mtss table:
#mtss
( [MM],[YYYY],[month_Start],[month_Finish],[ProjectID],[ProjectedBillable],[ProjectedPayable],[ActualBilled],[ActualPaid],[Total_To_Bill],[Total_To_Pay])
tbl_Snapshot ([MM],[YYYY],[month_Start],[month_Finish],[ProjectID],[ProjectedBillable],[ProjectedPayable],[ActualBilled],[ActualPaid],[Total_To_Bill],[Total_To_Pay]
)
I need to compare two tables and find matches
if tbl_snapshot [MM] and [ProjectId] matches then delete record in tbl_snapshot and insert record from #mtts.
Thanks in advance.
Since you're on 2008, you can use MERGE to perform the as a single logical operation:
;merge into tbl_Snapshot s
using #mtss m on s.MM = m.MM and s.ProjectId = m.ProjectId
when matched then update
set
YYYY = m.YYYY,
month_Start = m.month_Start
/* Other columns as well, not going to type them all out */
;
This would also easily extend to other cases you may have to deal with, if the data only exists in one table and not the other, with addition match clauses.
Of course, thinking further, in this case a simple UPDATE would work also. A DELETE followed by an INSERT (where the deleted and inserted rows are related by a key) is the equivalent of an UPDATE.
Somethig like:
DELETE tbl_snapshot
FROM tbl_snapshot ss
INNER JOIN #mtss m ON m.MM = ss.MM AND m.ProjectId = ss.ProjectId
(I wrote the code directly to this editor so it might have errors, but it should give you an idea how to continue)
I have two tables in Database , I need to select a field from one table and update it in another table with a condition where id is same .. Is it Possible to write in single query ???
This should work for you:
update storage
set storage.email = (select register.email
from register
where register.id = storage.id)
Yeah it is, you could do this for example:
UPDATE Origin SET DesiredColumn = NewValue
FROM Origin
JOIN NewTable ON Origin.Id = NewTable.Id
And guess the column names were like DesiredColumn in the updating table and NewValue in the table that holds the new value.
Yes, this is possible, although the syntax depends on the type of SQL you are using.
Here is an example for T-SQL (for Microsoft SQL Server)
UPDATE
S
SET
Email = R.Email
FROM
dbo.Register R
INNER JOIN dbo.Storage S
ON S.RegisterID = R.RegisterID
I am using Delphi 7, BDE, and Interbase (testing), Oracle (Production).
I have two tables (Master, Responses)
I need to step through the Responses table, use its Master_Id field to look it up in Master table (id) for matching record and update a date field in the Master table with a date field in the Responses table
Can this be done in SQL, or do i actually have to create two TTables or TQueries and step through each record?
Example:
Open two tables (Table1, Table2)
with Table1 do
begin
first;
while not EOF do
begin
//get master_id field
//locate in id field in table 2
//edit record in table 2
next;
end;
end;
thanks
One slight modification to Chris' query, throw in a where clause to select only the records that need the update. Otherwise it will set the rest of the dates to NULL
UPDATE Master m
SET
m.date = (SELECT r.date FROM Reponses r WHERE r.master_id = m.id)
WHERE m.id IN (SELECT master_id FROM Responses)
Updated to use aliases to avoid confusion which col comes from which table.
This is not ready made, copy-past'able query as UPDATE syntax differs from database to database.
You may need to consult your database sql reference for JOIN in UPDATE statement syntax.
When there are multiple responses to same master entry
UPDATE Master m
SET m.date = (
SELECT MAX(r.date) FROM Reponses r WHERE r.master_id = m.id)
WHERE m.id IN (SELECT master_id FROM Responses)
I used MAX() you can use whatever suits your business.
Again invest some time understanding SQL. Its hardly a few days effort. Get PLSQL Complete reference if you are into Oracle
Try this SQL (changing names to fit your situation)
UPDATE Master m
SET date = ( SELECT date FROM Responses WHERE id = m.id )