I got the following code ( no chance to ask the person who wrote it ) and don't see the need of the inner join on deleted. Do I miss something?
I thought, the deleted-table is used in instead-of-delete triggers. In instead-of-inserted triggers it's empty everytime, isn't it in instead-of-update triggers?
CREATE TRIGGER "someTrigger" ON "dbo"."someView"
INSTEAD OF UPDATE
AS
BEGIN
INSERT INTO "someOtherTable"
(
"id"
, "startTime"
, "endTime"
, "duration"
, "resourceId"
, "resourceLocked"
, "timeLocked"
, "groupPrefix"
)
SELECT
"id" = i."id"
, "startTime" = i."startTime"
, "endTime" = i."endTime"
, "duration" = ISNULL( i."duration", 0 )
, "resourceId" = i."resourceId"
, "resourceLocked" = ISNULL( i."resourceLocked", 0 )
, "timeLocked" = ISNULL( i."timeLocked", 0 )
, "groupPrefix" = N'gp'
FROM inserted AS i
INNER JOIN deleted AS d
ON d."id" = i."id"
WHERE ( i."jobType" != 3 )
OR ( i."jobType" = 3 AND i."startTime" != d."startTime" );
END;
In an update trigger, both inserted and deleted are populated. inserted contains the new row values, deleted contains the old row values, i.e. the values from before the UPDATE statement executed.
Here, it seems to be being used in the WHERE clause:
WHERE ( i."jobType" != 3 )
OR ( i."jobType" = 3 AND i."startTime" != d."startTime" );
So, if jobType is 3, we only do the insert if the startTime has been changed.
It should be noted that correlating the rows between inserted and deleted is only possible if at least one key's column(s) are not subject to update. Here, id appears to be a key. Hopefully that id column isn't subject to update or else this trigger may misbehave when such updates occur.
Related
We are running ECC6 on HANA, currently the extraction of RESB does a full table scan. I want to record that a change has happened to a Z table (I don't care what change).
I've attempted to create the triggers (in Word) from Help & Google, I would appreciate any suggestions for improvement.
create trigger tr_RESB_insert
after insert on RESB
referencing new row NR
for each row
begin
insert into ZBW_RESB_CDC (
MANDT
,RSNUM
,RSPOS
,RSART
,CHNGIND
,AEDAT
,AEZEIT
,AETMSTMP
,TZONE
,DELFLG )
values ( NR.MANDT
, NR.RSNUM
, NR.RSPOS
, NR.RSART
, ‘I’
, current_utcdate
, current_utctime
, current_utctimestamp
, ‘UTC’
,’ ’
)
end;
and
create trigger tr_RESB_update
after update on RESB
referencing new row NR
for each row
begin
merge ZBW_RESB_CDC as T
using NR
on ( NR.MANDT = T.MANDT and
,NR.RSNUM = T.RSNUM and
,NR.RSPOS = T.RSPOS and
,NR.RSART = T.RSART )
when matched then update
set T.CHNGIND = ‘U’
,T.AEDAT = current_utcdate
,T.AEZEIT = current_utctime
,T.AETMSTMP = current_utctimestamp
,T.TZONE = ‘UTC’
,T.DELFLG = ‘ ’
when not matched then insert (
MANDT
,RSNUM
,RSPOS
,RSART
,CHNGIND
,AEDAT
,AEZEIT
,AETMSTMP
,TZONE
,DELFLG )
values ( NR.MANDT
,NR.RSNUM
,NR.RSPOS
,NR.RSART
, ‘U’
, current_utcdate
, current_utctime
, current_utctimestamp
, ‘UTC’
,’ ’
end;
similarly for delete
At some time we'll upgrade to S4 but for the moment I would like to improve what we have.
I chose to use MERGE so that I don't need to initialise the table and so I can delete old records. Nor do I want to keep images of every change, just the fact that it has changed.
Thanks,
G.
I have python dict with relationship between elements and their values. For example:
db_rows_values = {
<element_uuid_1>: 12,
<element_uuid_2>: "abc",
<element_uuid_3>: [123, 124, 125],
}
And I need to update it in one query. I made it in python through the query generation loop with CASE:
sql_query_elements_values_part = " ".join([f"WHEN '{element_row['element_id']}' "
f"THEN '{ujson.dumps(element_row['value'])}'::JSONB "
for element_row in db_row_values])
query_part_elements_values_update = f"""
elements_value_update AS (
UPDATE m2m_entries_n_elements
SET value =
CASE element_id
{sql_query_elements_values_part}
ELSE NULL
END
WHERE element_id = ANY(%(elements_ids)s::UUID[])
AND entry_id = ANY(%(entries_ids)s::UUID[])
RETURNING element_id, entry_id, value
),
But now I need to rewrite it in plpgsql. I can pass db_rows_values as array of ROWTYPE or as json but how can I make something like WHEN THEN part?
Ok, I can pass dict as JSON, convert it to rows with json_to_recordset and change WHEN THEN to SET value = (SELECT.. WHERE)
WITH input_rows AS (
SELECT *
FROM json_to_recordset(
'[
{"element_id": 2, "value":"new_value_1"},
{"element_id": 4, "value": "new_value_2"}
]'
) AS x("element_id" int, "value" text)
)
UPDATE table1
SET value = (SELECT value FROM input_rows WHERE input_rows.element_id = table1.element_id)
WHERE element_id IN (SELECT element_id FROM input_rows);
https://dbfiddle.uk/?rdbms=postgres_14&fiddle=f8b6cd8285ec7757e0d8f38a1becb960
I am a newbie here.
I am using PostgreSQL to manipulate lots of data in my specific field of research. Unfortunately, I am encountering a problem that is not allowing me to continue my analysis. I tried to simplify my problem to clearly illustrate it.
Let's suppose I have a table called "Buyers" with those data:
table_buyers
The buyers can make ONLY ONE purchase in each store or none. There are three stores and there a table for each one. Just like below:
table_store1
table_store2
table_store3
To create the tables, I am using the following code:
CREATE TABLE public.buyer
(
ID integer NOT NULL PRIMARY KEY,
name text NOT NULL,
phone text NOT NULL
)
WITH (
OIDS = FALSE
)
;
CREATE TABLE public.Store1
(
ID_buyer integer NOT NULL PRIMARY KEY,
total_order numeric NOT NULL,
total_itens integer NOT NULL
)
WITH (
OIDS = FALSE
)
;
CREATE TABLE public.Store2
(
ID_buyer integer NOT NULL PRIMARY KEY,
total_order numeric NOT NULL,
total_itens integer NOT NULL
)
WITH (
OIDS = FALSE
)
;
CREATE TABLE public.Store3
(
ID_buyer integer NOT NULL PRIMARY KEY,
total_order numeric NOT NULL,
total_itens integer NOT NULL
)
WITH (
OIDS = FALSE
)
;
To add the information on the tables, I am using the following code:
INSERT INTO buyer (ID, name, phone) VALUES
(1, 'Alex', 88888888),
(2, 'Igor', 77777777),
(3, 'Mike', 66666666);
INSERT INTO Store1 (ID_buyer, total_order, total_itens) VALUES
(1, 87.45, 8),
(2, 14.00, 3),
(3, 12.40, 4);
INSERT INTO Store2 (ID_buyer, total_order, total_itens) VALUES
(1, 785.12, 7),
(2, 9874.21, 25);
INSERT INTO Store3 (ID_buyer, total_order, total_itens) VALUES
(2, 45.87, 1);
As all the tables are interconnected by buyer's ID, I wish I could have a query that generates an output just like this:
desired output table.
Please, note that if the buyer did not buy anything in a store, I must print '0'.
I know this is an easy task, but unfortunately, I have been failing on accomplish it.
Using the 'AND' logical operator, I tried the following code to accomplish this task:
SELECT
buyer.id,
buyer.name,
store1.total_order,
store2.total_order,
store3.total_order
FROM
public.buyer,
public.store1,
public.store2,
public.store3
WHERE
buyer.id = store1.id_buyer AND
buyer.id = store2.id_buyer AND
buyer.id = store3.id_buyer;
But, obviously, it just returned 'Igor' as this was the only buyer that have bought items on all three stores (print screen).
Then, I tried the 'OR' logical operator, just like the following code:
SELECT
buyer.id,
buyer.name,
store1.total_order,
store2.total_order,
store3.total_order
FROM
public.buyer,
public.store1,
public.store2,
public.store3
WHERE
buyer.id = store1.id_buyer OR
buyer.id = store2.id_buyer OR
buyer.id = store3.id_buyer;
But then, it returns 12 lines with wrong values (print screen).
Clearly, my mistake is about not considering that 'Buyers' don't have to on all three stores on my code. I just can't correct it on my own, can you please help me?
I appreciate a lot for an answer that can light up my way. Thanks a lot!
Tips about how I can search for this issue are very welcome as well!
Ok. I doubt that this is the final answer for you, but its a start
SELECT
buyer.id,
buyer.name,
COALESCE( gb_store1.total_orders, 0 ) as store1_total,
COALESCE( gb_store2.total_orders, 0 ) as store2_total,
COALESCE( gb_store3.total_orders, 0 ) as store3_total
FROM
public.buyer,
LEFT OUTER JOIN ( SELECT ID_buyer,
SUM( total_orders ) as total_orders,
SUM( total_itens ) as total_itens
FROM public.store1
GROUP BY ID_buyer ) gb_store1 ON gb_store1.id_buyer = buyer.id ,
LEFT OUTER JOIN ( SELECT ID_buyer,
SUM( total_orders ) as total_orders,
SUM( total_itens ) as total_itens
FROM public.store2
GROUP BY ID_buyer ) gb_store2 ON gb_store2.id_buyer = buyer.id ,
LEFT OUTER JOIN ( SELECT ID_buyer,
SUM( total_orders ) as total_orders,
SUM( total_itens ) as total_itens
FROM public.store3
GROUP BY ID_buyer ) gb_store3 ON gb_store3.id_buyer = buyer.id ;
So, this query has a couple elements should focus on. The subselects/groupby allow you to total within your subtables by ID_buyer. The LEFT OUTER JOIN make its so your query can still return a result, even if a subselect finds no matching record. Finally, the COALESCE allows you to return 0 when one of your totals is NULL (because the subselect found no match).
Hope this helps.
im working on procedure which should transfer number of items (value #p_count) from old store to new store
SET #countOnOldStore = (SELECT "count" FROM ProductStore WHERE StoreId = #p_oldStoreId AND ProductId = #p_productID)
SET #countOnNewStore = (SELECT "count" FROM ProductStore WHERE StoreId = #p_newStoreID AND ProductId = #p_productID)
SET #ShiftedCount = #countOnOldStore - #p_count
SET #newStoreAfterShift = #countOnNewStore + #p_count
IF #ShiftedCount > 0
BEGIN
DELETE FROM ProductStore WHERE storeId = #p_oldStoreId and productID = #p_productID
INSERT INTO ProductStore (storeId,productId,"count") VALUES (#p_oldStoreId,#p_productID,#ShiftedCount)
DELETE FROM ProductStore WHERE storeId = #p_newStoreID and productID = #p_productID
INSERT INTO ProductStore (storeId,productId,"count") VALUES (#p_newStoreID,#p_productID,#newStoreAfterShift)
END
ELSE
PRINT 'ERROR'
well ... second insert is not working. I cant figure it out. It says
Cannot insert the value NULL into column 'count', table 'dbo.ProductStore'; column does not allow nulls. INSERT fails.
Can anyone see problem and explain it to me ? Its school project
It looks like your entire query should just be:
UPDATE ProductStore
SET [count] = [count] + CASE
WHEN storeId = #p_NewStoreID THEN #p_Count
ELSE -#p_Count END
WHERE
productID = #p_ProductID and
storeID in (#p_NewStoreID,#p_OldStoreID)
If either value in the following is NULL, the total will be NULL:
SET #newStoreAfterShift = #countOnNewStore + #p_count
Check both values (#countOnNewStore, #p_count) for NULL.
Looks like you are not assigning any value to #p_count, so it is NULL and so are #ShiftedCount and #newStoreAfterShift.
There are two inserts in my trigger which is fired by an update. My Vendor_Hist table has a field called thID which is the primary key in Task_History table. thID gets its' value from mySeq.nextval.
INSERT INTO TASK_HISTORY
( thID, phId, LABOR, VERSION )
( select mySeq.NEXTVAL, mySeq2.CurrVal, LABOR, tmpVersion
from tasks t
where t.project_id = :new.project_ID );
select mySeq.currval into tmpTHID from dual; -- problem here!
INSERT INTO VENDOR_HIST
( vhID, thID, Amount, Position, version )
( select mySeq3.NEXTVAL, tmpTHID,
Amount, Position, tmpVersion
from vendors v2, tasks t2
where v2.myID = t2.myID
and t2.project_id = :new.project_ID );
Now, my problem is the tmpTHID always the latest value of mySeq.nextVal. So, if thID in task_history is 1,2,3, I get three inserts into vendor_hist table with 3,3,3. It has to be 1,2,3. I also tried
INSERT INTO TASK_HISTORY
( thID, phId, LABOR, VERSION )
( select mySeq.NEXTVAL, mySe2.CurrVal, LABOR, tmpVersion
from tasks t
where t.project_id = :new.project_ID ) returning thID into :tmpTHID;
but then I get a "warning compiled with errors" message when I execute the trigger. How do I make sure that the thID in first insert is also the same in my second insert?
Hope it makes sense.
for i in (select * from tasks t
where t.project_id = :new.project_id)
loop
insert into task_history
( thID, phId, LABOR, VERSION )
values
(mySeq.NEXTVAL, mySeq2.CurrVal, i.LABOR, i.tmpVersion);
for each j in (select * from vendors v
where i.myId = v.myId)
loop
insert into vendor_history
( vhID, thID, Amount, Position, version )
values
(mySeq3.NEXTVAL, mySeq.CURRVAL, j.Amount, j.Position, j.tmpVersion)
end loop;
end loop;
I'm assuming the columns inserted in the second insert are from the VENDORS table; if not, the referencing cursor (i or j) should be used as appropriate.
Instead of the currVal, it works with the following subselect.
( select min(thID) from task_history t3
where t3.project_id = t2.project_id
and t3.myID = t2.myID
and t3.version = tmpVersion ),