I am trying to perform a merge to insert and update as the case may be in a table. However in table 1, I only want it to insert the unique values of the tbl2.rfc field regardless if my other fields change, I only want to show the unique values of said field. I am occupying the ROW_NUMBER function to bring only unique values, but I have not been able to add this function to my merge.
MERGE INTO B69_TBL1 tbl1
USING (SELECT T1.*, ROW_NUMBER() OVER (PARTITION BY T1.rfc ORDER BY T1.rfc DESC) ENUMERADO
FROM B69_TBL2 tbl2
WHEN MATCHED THEN
UPDATE SET
tbl1.id_tbl1 = tbl2.id_con,
tbl1.rfc = tbl2.rfc,
tbl1.rfc = tbl2.name_cont
WHEN NOT MATCHED THEN
INSERT (tbl1.id_tbl1,tbl1.tbl1tipo,tbl1.id_concentrado,tbl1.rfc,
tbl1.name_cont,tbl1.baja_logica,tbl1.last_update)
VALUES (id_tbl1autt.nextval,'1','1',tbl2.id_concentrado,tbl2.rfc,
tbl2.name_cont,'0', '11/05/2021')
) T1
WHERE ENUMERADO=1
AND RFC IS NOT NULL
The error it marks is 00907. 00000 - "missing right parenthesis"
because I had it like this and it fails precisely in the on.
MERGE INTO B69_TBL1 tbl1
USING (SELECT T1.*, ROW_NUMBER() OVER (PARTITION BY T1.rfc ORDER BY T1.rfc DESC) ENUMERADO
ON tbl1.rfc = tbl2.rfc
FROM B69_TBL2 tbl2 )
WHEN MATCHED THEN
UPDATE SET
tbl1.id_alert = tbl2.id_con,
tbl1.rfc = tbl2.rfc,
tbl1.rfc = tbl2.name_cont
WHEN NOT MATCHED THEN
INSERT (tbl1.id_alert,tbl1.alertype,tbl1.id_con,tbl1.rfc,
tbl1.name_cont,tbl1.baja_logica,tbl1.last_update)
VALUES (id_tbl1autt.nextval,'1','1',tbl2.id_con,tbl2.rfc,
tbl2.name_cont,'0', '11/05/2021')
) T1
WHERE ENUMERADO=1
AND RFC IS NOT NULL
Your ON clause is in the wrong place;
You had the tbl2 alias inside the USING query instead of following it;
You do not need the tbl1 aliases before the destination column names in the UPDATE or INSERT;
You are updating the rfc column twice (I removed the second instance);
There was a strange T1 alias after the insert that should be inside the USING query; and
You can use a DATE literal rather than a string.
There may be other errors, as I do not have your tables to test the query.
MERGE INTO B69_TBL1 tbl1
USING (
SELECT T1.*,
ROW_NUMBER() OVER (PARTITION BY T1.rfc ORDER BY T1.rfc DESC) AS ENUMERADO
FROM B69_TBL2 t1
) tbl2
ON tbl1.rfc = tbl2.rfc
WHEN MATCHED THEN
UPDATE SET
id_alert = tbl2.id_con,
rfc = tbl2.rfc
WHEN NOT MATCHED THEN
INSERT (
id_alert,
alertype,
id_con,
rfc,
name_cont,
baja_logica,
last_update
) VALUES (
id_tbl1autt.nextval,
'1',
'1',
tbl2.id_con,
tbl2.rfc,
tbl2.name_cont,
'0',
DATE '2021-05-11'
)
WHERE ENUMERADO=1
AND RFC IS NOT NULL
I have a requirement to do matching of few attributes one by one. I'm looking to avoid multiple select statements. Below is the example.
Table1
Col1|Price|Brand|size
-----------------------
A|10$|BRAND1|SIZE1
B|10$|BRAND1|SIZE1
C|30$|BRAND2|SIZE2
D|40$|BRAND2|SIZE4
Table2
Col1|Col2|Col3
--------------
B|XYZ|PQR
C|ZZZ|YYY
Table3
Col1|COL2|COL3|LIKECOL1|Price|brand|size
-----------------------------------------
B|XYZ|PQR|A|10$|BRAND1|SIZE1
C|ZZZ|YYY|D|NULL|BRAND2|NULL
In table3, I need to insert data from table2 by checking below conditions.
Find a match for record in table2, if Brand and size, Price match
If no match found, then try just Brand, Size
still no match found, try brand only
In the above example, for the first record in table2, found match with all the 3 attributes and so inserted into table3 and second record, record 'D' is matching but only 'Brand'.
All I can think of is writing 3 different insert statements like below into an oracle pl/sql block.
insert into table3
select from tab2
where all 3 attributes are matching;
insert into table3
select from tab2
where brand and price are matching
and not exists in table3 (not exists is to avoid
inserting the same record which was already
inserted with all 3 attributes matched);
insert into table3
select from tab2
where Brand is matching and not exists in table3;
Can anyone please suggest a better way to achieve it in any better way avoiding multiple times selecting from table2.
This is a case for OUTER APPLY.
OUTER APPLY is a type of lateral join that allows you join on dynamic views that refer to tables appearing earlier in your FROM clause. With that ability, you can define a dynamic view that finds all the matches, sorts them by the pecking order you've specified, and then use FETCH FIRST 1 ROW ONLY to only include the 1st one in the results.
Using OUTER APPLY means that if there is no match, you will still get the table B record -- just with all the match columns null. If you don't want that, you can change OUTER APPLY to CROSS APPLY.
Here is a working example (with step by step comments), shamelessly stealing the table creation scripts from Michael Piankov's answer:
create table Table1 (Col1,Price,Brand,size1)
as select 'A','10','BRAND1','SIZE1' from dual union all
select 'B','10','BRAND1','SIZE1' from dual union all
select 'C','30','BRAND2','SIZE2' from dual union all
select 'D','40','BRAND2','SIZE4'from dual
create table Table2(Col1,Col2,Col3)
as select 'B','XYZ','PQR' from dual union all
select'C','ZZZ','YYY' from dual;
-- INSERT INTO table3
SELECT t2.col1, t2.col2, t2.col3,
t1.col1 likecol1,
decode(t1.price,t1_template.price,t1_template.price, null) price,
decode(t1.brand,t1_template.brand,t1_template.brand, null) brand,
decode(t1.size1,t1_template.size1,t1_template.size1, null) size1
FROM
-- Start with table2
table2 t2
-- Get the row from table1 matching on col1... this is our search template
inner join table1 t1_template on
t1_template.col1 = t2.col1
-- Get the best match from table1 for our search
-- template, excluding the search template itself
outer apply (
SELECT * FROM table1 t1
WHERE 1=1
-- Exclude search template itself
and t1.col1 != t2.col1
-- All matches include BRAND
and t1.brand = t1_template.brand
-- order by match strength based on price and size
order by case when t1.price = t1_template.price and t1.size1 = t1_template.size1 THEN 1
when t1.size1 = t1_template.size1 THEN 2
else 3 END
-- Only get the best match for each row in T2
FETCH FIRST 1 ROW ONLY) t1;
Unfortunately is not clear what do you mean when say match. What is you expectation if there is more then one match?
Should it be only first matching or it will generate all available pairs?
Regarding you question how to avoid multiple inserts there is more then one way:
You could use multitable insert with INSERT first and condition.
You could join table1 to self and get all pairs and filter results in where condition
You could use analytical function
I suppose there is another ways. But why you would like to avoid 3 simple inserts. Its easy to read and maintain. And may be
There is example with analytical function next:
create table Table1 (Col1,Price,Brand,size1)
as select 'A','10','BRAND1','SIZE1' from dual union all
select 'B','10','BRAND1','SIZE1' from dual union all
select 'C','30','BRAND2','SIZE2' from dual union all
select 'D','40','BRAND2','SIZE4'from dual
create table Table2(Col1,Col2,Col3)
as select 'B','XYZ','PQR' from dual union all
select'C','ZZZ','YYY' from dual
with s as (
select Col1,Price,Brand,size1,
count(*) over(partition by Price,Brand,size1 ) as match3,
count(*) over(partition by Price,Brand ) as match2,
count(*) over(partition by Brand ) as match1,
lead(Col1) over(partition by Price,Brand,size1 order by Col1) as like3,
lead(Col1) over(partition by Price,Brand order by Col1) as like2,
lead(Col1) over(partition by Brand order by Col1) as like1,
lag(Col1) over(partition by Price,Brand,size1 order by Col1) as like_desc3,
lag(Col1) over(partition by Price,Brand order by Col1) as like_desc2,
lag(Col1) over(partition by Brand order by Col1) as like_desc1
from Table1 t )
select t.Col1,t.Col2,t.Col3, coalesce(s.like3, like_desc3, s.like1, like_desc1, s.like1, like_desc1),
case when match3 > 1 then size1 end as size1,
case when match1 > 1 then Brand end as Brand,
case when match2 > 1 then Price end as Price
from table2 t
left join s on s.Col1 = t.Col1
COL1 COL2 COL3 LIKE_COL SIZE1 BRAND PRICE
B XYZ PQR A SIZE1 BRAND1 10
C ZZZ YYY D - BRAND2 -
I have two tables. if the data in table1 is more than a predefined limit (say 2), i need to copy the remaining contents of table1 to table2 and delete those same contents from table1.
I used the below query to insert the excess data from table1 to table2.
insert into table2
SELECT * FROM table1 WHERE ROWNUM < ((select count(*) from table1)-2);
Now i need the delete query to delete the above contents from table1.
Thanks in advance.
A straightforward approach would be an interim storage in a temporary table. Its content can be used to determine the data to be deleted from table1 as well as the source to feed table 2.
Assume (slightly abusing notation) to be the PK column (or that of any candidate key) of table1 - usually there'll be some key that comprises only 1 column.
create global temporary table t_interim as
( SELECT <pk> pkc FROM table1 WHERE ROWNUM < ((select count(*) from table1)-2 )
;
insert into table2
select * from table1 where <pk> IN (
select pkc from t_interim
);
delete from table1 where <pk> IN (
select pkc from t_interim
);
Alternative
If any key of table1 spans more than 1 column, use an EXISTS clause instead as follows ( denoting the i-th component of a candidate key in table1):
create global temporary table t_interim as
( SELECT <ck_1> ck1, <ck_2> ck2, ..., <ck_n> ckn FROM table1 WHERE ROWNUM < ((select count(*) from table1)-2 )
;
insert into table2
select * from table1 t
where exists (
select 1
from t_interim t_i
where t.ck_1 = t_i.ck1
and t.ck_2 = t_i.ck2
...
and t.ck_n = t_i.ckn
)
;
delete from table1 t where
where exists (
select 1
from t_interim t_i
where t.ck_1 = t_i.ck1
and t.ck_2 = t_i.ck2
...
and t.ck_n = t_i.ckn
)
;
(Technically you could try to adjust the first scheme by synthesizing a key from the components of any CK, eg. by concatenating. You run the risk of introducing ambiguities ( (a bc, ab c) -> (abc, abc) ) or run into implementation limits ( max. varchar length ) using the first method)
Note
In case the table doesn't have a PK, you can apply the technique using any candidate key of table1. There will always be one, in the extreme case it's the set of all columns.
This situation may be the right time to improve the db design and add a (synthetic) pk column to table1 ( and any other tables in the system that lack it).
I'm trying to build a query in Toad Data Point. I have a subquery that has a row number to identify the records I'm interested in. This subquery needs to be left joined onto the main table only when the row number is 1. Here's the query I'm trying to visualize:
SELECT distinct E.EMPLID, E.ACAD_CAREER
FROM PS_STDNT_ENRL E
LEFT JOIN (
SELECT ACAD_CAREER, ROW_NUMBER() OVER (PARTITION BY ACAD_CAREER ORDER BY EFFDT DESC) as RN
FROM PS_ACAD_CAR_TBL
) T on T.ACAD_CAREER = E.ACAD_CAREER and RN = 1
When I try to replicate this, the row number condition is placed in the global WHERE clause. This is not the intended functionality because it removes any records that don't have a match in the subquery effectively making it an inner join.
Here is the query it's generating:
SELECT DISTINCT E.EMPLID, E.ACAD_CAREER, T.RN
FROM SYSADM.PS_STDNT_ENRL E
LEFT OUTER JOIN
(SELECT PS_ACAD_CAR_TBL.ACAD_CAREER,
ROW_NUMBER ()
OVER (PARTITION BY ACAD_CAREER ORDER BY EFFDT DESC)
AS RN
FROM SYSADM.PS_ACAD_CAR_TBL PS_ACAD_CAR_TBL) T
ON (E.ACAD_CAREER = T.ACAD_CAREER)
WHERE (T.RN = 1)
Is there a way to get the query builder to place that row number condition on the left join instead of the global WHERE clause?
I found a way to get this to work.
Add a calculated field to the main table with a value of 1.
Join the row number to this new calculated field.
Now the query has the filter in the join condition instead of the WHERE clause so that it joins as intended. Here is the query it made:
SELECT DISTINCT E.EMPLID, E.ACAD_CAREER, T.RN
FROM SYSADM.PS_STDNT_ENRL E
LEFT OUTER JOIN
(SELECT PS_ACAD_CAR_TBL.ACAD_CAREER,
ROW_NUMBER ()
OVER (PARTITION BY ACAD_CAREER ORDER BY EFFDT DESC)
AS RN
FROM SYSADM.PS_ACAD_CAR_TBL PS_ACAD_CAR_TBL) T
ON (E.ACAD_CAREER = T.ACAD_CAREER) AND (1 = T.RN)
I have a table ( table1 ) that represents item grouping and another table ( table2 ) that represents the items themselves.
table1.id is foreign key to table2 and in every record of table1 I also collect information like the total number of records in table2 associated with that particular record and the sum of various fields so that I can show the grouping and a summary of what's in it without having to query table2.
Usually items in table2 are added/removed one at a time, so I update table1 to reflect the changes in table2.
A new requirement arose, choosen items in a group must be moved to a new group. I thought of it as a 3 step operation:
create a new group in table1
update choosen records in table2 to point to the newly created rec in table1
the third step would be to subtract to the group the number of records / the sum of those other fields I need do show and add them to the new group, data that I can find simply querying table2 for items associated with the new group.
I came up with the following statement that works.
update table1 t1 set
countitems = (
case t1.id
when 1 then t1.countitems - ( select count( t2.id ) from table2 t2 where t2.id = 2 )
when 2 then ( select count( t2.id ) from table2 t2 where t2.id = 2 )
end
),
sumitems = (
case t1.id
when 1 then t1.sumitems - ( select sum( t2.num ) from table2 t2 where t2.id = 2 )
when 2 then ( select sum( t2.num ) from table2 t2 where t2.id = 2 )
end
)
where t1.id in( 1, 2 );
is there a way to rewrite the statement without having to repeat the subquery every time?
thanks
Piero
You can use a cursor and a bulk collect update statement on the rowid. That way you can simply write the join query with the desired result and update the table with those values. I always use this function and make slight adjustments each time.
declare
cursor cur_cur
IS
select ti.rowid row_id
, count(t2.id) countitems
, sum(t2.num) numitems
from table t1
join table t2 on t1.id = t2.t1_id
order by row_id
;
type type_rowid_array is table of rowid index by binary_integer;
type type_countitems_array is table of table1.countitems%type;
type type_numitems_array is table of table1.numitems%type;
arr_rowid type_rowid_array;
arr_countitems type_countitems_array;
arr_numitems type_numitems_array;
v_commit_size number := 10000;
begin
open cur_cur;
loop
fetch cur_cur bulk collect into arr_rowid, arr_countitems, arr_numitems limit v_commit_size;
forall i in arr_rowid.first .. arr_rowid.last
update table1 tab
SET tab.countitems = arr_countitems(i)
, tab.numitems = arr_numitems(i)
where tab.rowid = arr_rowid(i)
;
commit;
exit when cur_cur%notfound;
end loop;
close cur_cur;
commit;
exception
when others
then rollback;
raise_application_error(-20000, 'ERROR updating table1(countitems,numitems) - '||sqlerrm);
end;