I have a table called txn_detail which has the primary key txn_id and an Advance Queue table called hlr_pre_qt that has the Primary Key of txn_detail inside a column called user_data with several other values separated by commas. I need to filter them out and make a mapping between the two tables using these two columns (txn_detail.txn_id and hlr_pre_qt.user_data). How can i do this?
You can use like to do the join
i.e.
SELECT *
FROM txn_detail A
JOIN hlr_pre_qt B on B.user_data.txn_id = A.txn_id
OR
SELECT *
FROM txn_detail A
JOIN hlr_pre_qt B on b.USER_DATA LIKE '%' || TO_CHAR(A.txn_id) || '%'
OR
You can strip the TXN_ID from user_data....
SELECT *
FROM txn_detail A
JOIN hlr_pre_qt B on
SUBSTR(b.USER_DATA, INSTR(b.USER_DATA, '(') +1, INSTR(b.USER_DATA, ',') - INSTR(b.USER_DATA, '(') - 1) = TO_CHAR(A.txn_id)
In both cases, no index will be used to do the join, so performance will be poor.
Hope that helps
Related
I'm trying to Right join two table on a column named "compte"
I need to do an addition after. The problem is that some "compte" doesn't exist in one of the table and as a result, the addition return null instead of keeping the based value
Here's the query
SELECT t.compte,t.posdev+x.mnt
FROM (
SELECT compte,SUM(mntdev) as mnt FROM mvtc22
WHERE compte IN ('11510198451','00610198451','40010198451','40010198453','00610198461','00101980081','00101980094',
'00101980111','40010198461','40010198462','40010198466','40010198463')
AND datoper BETWEEN '01/01/22' AND '06/01/22'
GROUP BY compte
)x
RIGHT OUTER JOIN
(
SELECT c.compte,c.posdev
FROM v_sldoper c
WHERE c.compte IN ('11510198451','00610198451','40010198451','40010198453','00610198461','00101980081','00101980094',
'00101980111','40010198461','40010198462','40010198466','40010198463')
AND datpos = '31/12/21'
)t
ON t.compte = x.compte
And the results :
I'm expecting to keep the results from the second subquery if there's no "compte" in the first subquery.
Thanks In advance,
Alex
You are very close, the problem is that in oracle SQL the result of any value + null value is null, so you need to handle potential null values from each column before applying the + operator betwen them.
To solve the issue, you can apply functions like NVL or decode or even CASE WHEN for that purpose.
Below I use NVL function to solve it (I assume t.posdev column cannot contain null values, otherwise apply nvl function to both columns).
SELECT t.compte, t.posdev + NVL(x.mnt, 0)
FROM (
SELECT compte,SUM(mntdev) as mnt FROM mvtc22
WHERE compte IN ('11510198451','00610198451','40010198451','40010198453','00610198461','00101980081','00101980094',
'00101980111','40010198461','40010198462','40010198466','40010198463')
AND datoper BETWEEN '01/01/22' AND '06/01/22'
GROUP BY compte
)x
RIGHT OUTER JOIN
(
SELECT c.compte,c.posdev
FROM v_sldoper c
WHERE c.compte IN ('11510198451','00610198451','40010198451','40010198453','00610198461','00101980081','00101980094',
'00101980111','40010198461','40010198462','40010198466','40010198463')
AND datpos = '31/12/21'
)t
ON t.compte = x.compte
I have a sql that is selecting many things from the database however I would like that data to only comeback which is matched to a personal table I have.
I would like to join a column [vin_code] from my table [population] however there are nulls in here and were there are nulls I would like to join another column from my table to another table in the database.
I will give an example sql below:
Select distinct v.kegal_rntity_id
From vin v
Inner join ops$dami.population pop
On v.vin_code = pop.vin_code
Then were pop.vin_code is null I would like to join pop.vis_code on a table in the database called zegal_rentity z column z.vis_code
So something like
join zegal_rentity z
On pop.vis_code = z.vis_code
But I only want to do this were pop.vin_code is null
As sample data is not available, I am unable to test the solution but try the following query with condition based outer join.
Select distinct v.kegal_rntity_id
From ops$dami.population pop
Left join vin v
On v.vin_code = pop.vin_code
Left join zegal_rentity z
On (case when pop.vin_code is null and
pop.vis_code = z.vis_code then 1 end = 1);
Cheers!!
I have two table say A and B in Hive. table A has "position" column and table B has "startposition" and "endposition" column. I am trying to do something like .
select * from A where position between (select startposition from B) AND (select endposition from B);
But it is not working and given exception .
how could we do that so each position of table A is check against each pair of startposition and endposition of table B.
select
position
from A
join B
where
A.position > B.startposition AND A.position<B.endposition;
LanguageManual Joins
Think of my two tables have the same columns. One column is the ID, and the other one is the text. Is it possible to implement the following pseudo code in PLSQL?
Compare each row (They will have the same ID)
If anything is different about them
Run a couple of queries: an Update, and an Insert
ElseIf they are the same
Do nothing
Else the row does not exist
So add the row to the table compared on
Is it easy to do this using PLSQL or should I create a standalone application to do do this logic.
As your table have the same columns, by using NATURAL JOIN you can easily check if two corresponding rows are identical -- without need to update your code if a column is added to your table.
In addition, using OUTER JOIN allow you to find the rows present in one table but not in the other.
So, you can use something like that to achieve your purpose:
for rec in (
SELECT T.ID ID1,
U.ID ID2,
V.EQ
FROM T
FULL OUTER JOIN U ON T.ID = U.ID
FULL OUTER JOIN (SELECT ID, 1 EQ FROM T NATURAL JOIN U) V ON U.ID = V.ID)
loop
if rec.id1 is null
then
-- row in U but not in T
elsif rec.id2 is null
then
-- row in T but not in U
elsif rec.eq is null
-- row present in both tables
-- but content mismatch
end if
end loop
Else the row does not exist
So add the row to the table compared on
Is this condition means that rows can be missed in both tables? If only in one, then:
insert into t1 (id, text)
select id, text
from t2
minus
select id, text
from t1;
If missed records can be in both tables, you need the same query that inserts into table t2 rows from t1.
If anything is different about them
If you need one action for any amount of different rows, then use something like this:
select count(*)
into a
from t1, t2
where t1.id = t2.id and t1.text <> t2.text;
if a > 0 then
...
otherwise:
for i in (
select *
from t1, t2
where t1.id = t2.id and t1.text <> t2.text) loop
<do something>
end loop;
A 'merge' statement is what u needed.
Here is the syntax:
MERGE INTO TARGET_TABLE
USING SOURCE_TABLE
ON (CONDITION)
WHEN MATCHED THEN
UPDATE SET (DO YOUR UPDATES)
WHEN NOT MATCHED THEN
(INSERT YOUR NEW ROWS)
Google MERGE syntax for more about the statement.
Just use MINUS.
query_1
MINUS
query_2
In your case, if you really want to use PL/SQL, then select count into a local variable. Write a logic, if count > 0 then do other stuff.
I have following query:
select id,
c1,
c2,
c3
from tbl t1
join
(select id
from tbl t2
where upper(replace(c5, ' ', '')) like upper(?)
) j
on j.id = t1.id
? is some wildcard parameter string like %test%.
c5 column has index on the function used to access it:
create index tbl_c5_idx on tbl(upper(replace(c5, ' ', '')))
When I run just inner query it uses tbl_c5_idx, however when I run the whole query it turns into full table scan which is much slower.
Are there any way to avoid full table scans? Hints or rewrite join condition. I can not rewrite whole query as inner query is constructed dynamically depending on the input conditions.
A very basic example to test your functionality
create table test(id number,value varchar2(200));
insert into test values(1,'gaurav is bad guy');
insert into test values(2,'gaurav is good guy');
SELECT *
FROM test
WHERE UPPER (REPLACE (VALUE, ' ', '')) LIKE UPPER ('%gauravisbad%');
before creating index this is doing a full table scan for obvious reason ,because no index get created.
create index tbl_c5_idx on test(upper(replace(value, ' ', '')));
The reason why i am asking you to avoid inner join on the same table because you're using the table twice once to get your records from your filter condition where your index are used and then join on the basis of id which is preventing of using index ,because you dont have index on id column,this can be done with a simple filter condition.
Please let me know if you're again finding out the same issue of full table scan ,or you're not getting the same result from this query .
if you're running the subquery only, it doesn't use the id column in the filters the way the parent query does, therefore the index can be used. In the parent query you are using the id as well, which prevents the index from being used. Maybe adding an index on (id, upper(replace(c5, ' ', ''))) would solve the problem.
Gaurav Soni is right: you don't need a subquery to achieve your goal.
always check performances rather than the explain plan. Performances might just be worst with your hint than without. Oracle is NOT stupid.
Seems I found solution, or at least a thing that helps.
I used index hint, so access is done with tbl_c5_idx.
That is how final query looks now:
select /*+ index(t1) */ id,
c1,
c2,
c3
from tbl t1
join
(select id
from tbl t2
where upper(replace(c5, ' ', '')) like upper(?)
) j
on j.id = t1.id