I want to have 2 join condition between two tables, first join condition should work always but the second Join condition should work only if condition is satisfied other wise give the result based on first two join.
I have two way one is directly give two condition and then add case statement
for third join
second I tried to have case statement after ON For first case I had 1 join condition and for second case 2 put 2 Join Condition.
SELECT *,IND.bill_to_id FROM txn_sales_shippedorders_intl shippedorders
LEFT JOIN ( SELECT cust_sid, max(cust_key) cust_key
,cust_nbr
FROM com_hub.ref_customer_hco_intl
GROUP BY cust_sid, cust_nbr
) cust ON cust.cust_sid = regexp_replace(shippedorders.cust_align_sid, "\\.0*", '')
--AND cust.country_cd = shippedorders.country_cd
AND cust.src_sys_id=shippedorders.src_sys_id
LEFT JOIN
(SELECT CUSTOMER,ship_to_id, bill_to_id
FROM com_lake.ref_india_customer_crossmap
) ind ON case when substr(SDVR02,1,2) ='IM'
and ind.ship_to_id = cust.cust_nbr then 1
WHEN substr(SDVR02,1,2) ='ER' and ind.CUSTOMER = cust.cust_name then 1
else 0
end 1
At the moment your join doesn't make sense. You have to look at the result of your case statement.
At the moment it reads:
Left JOIN (...) ind ON 0
or
Left Join (...) ind on 1
You need to have an argument - e.g.
Left JOIN (...) ind on ind.index = CASE WHEN ...
Related
I want to have rows which appeared in 25th of February and did not appear in 6th of March. I've tried to do such query:
SELECT favfd.day, dv.title, array_to_string(array_agg(distinct "host_name"), ',') AS affected_hosts , htmltoText(dsol.fix),
count(dv.title) FROM fact_asset_vulnerability_finding_date favfd
INNER JOIN dim_vulnerability dv USING(vulnerability_id)
INNER JOIN dim_asset USING(asset_id)
INNER JOIN dim_vulnerability_solution USING(vulnerability_id)
INNER JOIN dim_solution dsol USING(solution_id)
INNER JOIN dim_solution_highest_supercedence dshs USING (solution_id)
WHERE (favfd.day='2018-02-25' OR favfd.day='2018-03-06') AND
dsol.solution_type='PATCH' AND dshs.solution_id=dshs.superceding_solution_id
GROUP BY favfd.day, dv.title, host_name, dsol.fix
ORDER BY favfd.day, dv.title
which gave me following results:
results
I've read that I need to add something like "HAVING COUNT(*)=1" but like you can see in query results my count columns looks quite weird. Here is my results with that line added:
results with having
Can you advice me what I am doing wrong?
One way is to use a HAVING clause to assert your date criteria:
SELECT
dv.title,
array_to_string(array_agg(distinct "host_name"), ',') AS affected_hosts,
htmltoText(dsol.fix),
count(dv.title)
FROM fact_asset_vulnerability_finding_date favfd
INNER JOIN dim_vulnerability dv USING(vulnerability_id)
INNER JOIN dim_asset USING(asset_id)
INNER JOIN dim_vulnerability_solution USING(vulnerability_id)
INNER JOIN dim_solution dsol USING(solution_id)
INNER JOIN dim_solution_highest_supercedence dshs USING (solution_id)
WHERE
dsol.solution_type = 'PATCH' AND
dshs.solution_id = dshs.superceding_solution_id
GROUP BY dv.title, dsol.fix
HAVING
SUM(CASE WHEN favfd.day = '2018-02-25' THEN 1 ELSE 0 END) > 0 AND
SUM(CASE WHEN favfd.day = '2018-03-06' THEN 1 ELSE 0 END) = 0
ORDER BY favfd.day, dv.title
The only major changes I made were to remove host_name from the GROUP BY clause, because you use this column in aggregate, in the select clause. And I added the HAVING clause to check your logic.
The change you should make is to replace your implicit join syntax with explicit joins. Putting join criteria into the WHERE clause is considered bad practice nowadays.
Query 1
select count(1)
from sdb_snmp_sysdata s
left join sdb_snmp_entphysicaltable e on s.source = e.source **and e.class = 3**
left join SDB_DF_DEVICE_DNS dns on dns.source = s.source
left join sdb_fdb_node f on upper(f.oldnodeid) = upper(dns.dns_name)
where (regexp_like(s.descr, 'NFXS-F FANT-F ALCATEL-LUCENT|Motorola APEX3000')
or regexp_like(e.descr, 'Motorola BSR64000 HD 100A Redundant Chassis|AS2511-RJ chassis')
or trim(e.ModelName) in ('RFGW1', 'ARCT01949', 'ARCT03253', 'UBR10012', 'WS-C3750-48TS-S', 'WS-C3750V2-48TS-S')
or e.name like '%Nexus5596 Chassis%')
Query 2:
select count(1)
from sdb_snmp_sysdata s
left join sdb_snmp_entphysicaltable e on s.source = e.source
left join SDB_DF_DEVICE_DNS dns on dns.source = s.source
left join sdb_fdb_node f on upper(f.oldnodeid) = upper(dns.dns_name)
where (regexp_like(s.descr, 'NFXS-F FANT-F ALCATEL-LUCENT|Motorola APEX3000')
or regexp_like(e.descr, 'Motorola BSR64000 HD 100A Redundant Chassis|AS2511-RJ chassis')
or trim(e.ModelName) in ('RFGW1', 'ARCT01949', 'ARCT03253', 'UBR10012', 'WS-C3750-48TS-S', 'WS-C3750V2-48TS-S')
or e.name like '%Nexus5596 Chassis%') **and e.class = 3**
The above two queries return different number of rows by changing e.class condition from on clause to where clause. I am unable to figure out. any help is appreciated.
My Understanding:
query 1 left outer join between sysdata and entphysicaltable hash join happens after full scan of individual tables.
in the second query 2 join happens after entphysicaltable is reduced to records containing only entphysicaltable.class = 3.
to me the query makes same sense but returns different results.
I can relate to this question I would like to know a concrete reason.
The best explanation is on a little example. Let have two tables
TABLE A
C1
----------
1
2
TABLE B
C1 C2
---------- -
1 x
Then the query with the filter B.c2 = 'x' in the ON clause returns 2 rows
select *
from A left outer join B
on A.c1 = B.c1 and B.c2 = 'x';
C1 C1 C2
---------- ---------- --
1 1 x
2
while when the filter is moved in the WHERE clause, only one row is delivered
select *
from A left outer join B
on A.c1 = B.c1
WHERE B.c2 = 'x';
C1 C1 C2
---------- ---------- --
1 1 x
The WHERE clause simple overrules the OUTER JOIN row missing logik - wee all know that NULL is not equal 'x', so the second row is discarded.
BWT if you see in the old join syntax constructs like B.c2(+) = 'x' this is the very same thema.
If I read your question right, then it simply comes down to how a LEFT JOIN works.
The way a (outer) LEFT JOIN works is that it will join what's on your left side with what's on your right side.
And then it being an outer join it will try to add NULL values to the right, for the situation where there is no match on the right.
However, by you adding your constraints in the WHERE clause, you're telling the query engine to filter out the rows where there is NULL because they will not match your WHERE clause.
If you have the filters in your ON clause - the query engine will not remove/filter out the NULL rows.
This happens because the WHERE is 'executed' after the JOINs.
That's why you get different number of rows, because an OUTER join functions differently based on whether you use the ON or the WHERE clause.
So if you want the join to include NULL rows, you'll need to use the ON clause.
In my query, I select a column which cannot exist because this column comes from a subquery in a join. (The subquery can give me 0 lines)
Consequently, in this case, I want to select 0 instead of "temp.Quantity" column.
The code:
SELECT
bx.BX_BoxNum,
temp.Quantity -- <- this column
FROM BOX bx
INNER JOIN (SELECT BX_Id, SUM(BX_Quantity) AS Quantity FROM BOX
WHERE BX_Top_S = 'True' GROUP BY BX_Id) temp
ON bx.BX_Id = temp.BX_Id
WHERE bx.BX_BoxNum = 10
Sometimes a box number is empty! And I try to have a line with "BOX n°10 -- 0" instead of nothing
Could you please help me?
SELECT bx.BX_BoxNum, ISNULL(temp.Quantity, 0)
FROM BOX bx
left outer JOIN (SELECT BX_Id, SUM(BX_Quantity) AS Quantity FROM BOX
WHERE BX_Top_S = 'True' GROUP BY BX_Id) temp ON bx.BX_Id = temp.BX_Id
WHERE bx.BX_BoxNum = 10
Outer joins allow selects to happen when one side of a join returns nothing. Inner Joins have to have rows on both sides of the join (as you've found!). Google for the differences between LEFT, RIGHT and FULL Outer joins.
SELECT bx.BX_BoxNum, SUM(COALESCE(temp.Quantity, 0)) AS Quantity
FROM BOX bx
LEFT JOIN BOX temp ON bx.BX_Id = temp.BX_Id AND temp.BX_Top_S = 'True'
WHERE bx.BX_BoxNum = 10
GROUP BY bx.BX_BoxNum
I'm working on a problem with two tables. Charge and ChargeHistory. I want to display a selection of columns from both tables where either the matching row in ChargeHistory has a different value and/or date from Charge or if there is no matching entry in ChargeHistory at all.
I'm using a left outer join declared using the ansi standard and while it does show the rows correctly where there is a difference, it isn't showing the null entries.
I've read that there can sometimes be issues if you are using the WHERE clause as well as the ON clause. However when I try and put all the conditons in the ON clause the query takes too long > 15 minutes (so long I have just cancelled the runs).
To make things worse both tables use a three part compound key.
Does anyone have any ideas as to why the null values are being left out?
SELECT values...
FROM bcharge charge
LEFT OUTER JOIN chgHist history
ON charge.key1 = history.key1 AND charge.key2 = history.key2 AND charge.key3 = history.key3 AND charge.chargeType = history.chargeType
WHERE charge.chargeType = '2'
AND (charge.value <> history.value OR charge.date <> history.date)
ORDER BY key1, key2, key
You probably want to explicitly select the null values:
SELECT values...
FROM bcharge charge
LEFT OUTER JOIN chgHist history
ON charge.key1 = history.key1 AND charge.key2 = history.key2 AND charge.key3 = history.key3 AND charge.chargeType = history.chargeType
WHERE charge.chargeType = '2'
AND ((charge.value <> history.value or history.value is null) OR (charge.date <> history.date or history.date is null))
ORDER BY key1, key2, key
You can explicitly look for a match in the where. I would recommend looking at one of the keys used for the join:
SELECT . . .
FROM bcharge charge LEFT OUTER JOIN
chgHist history
ON charge.key1 = history.key1 AND charge.key2 = history.key2 AND
charge.key3 = history.key3 AND charge.chargeType = history.chargeType
WHERE charge.chargeType = '2' AND
(charge.value <> history.value OR charge.date <> history.date OR history.key1 is null)
ORDER BY key1, key2, key;
The expressions charge.value <> history.value change the left outer join to an inner join because NULL results will be filtered out.
A WHERE clause filters the data returned by a join. Therefore when your inner table has null data for a particular column, the corresponding rows get filtered out based on your specified condition. That is why you should move that logic to the ON clause instead.
For the performance issues, you could consider adding indexes on the columns used for joining and filtering.
Have a look at this site, it will be very helpful for you, visual illustration of all the join statements with code samples
blog.codinghorror.com
Quoted of the relevant info in the above link:
SELECT * FROM TableA
LEFT OUTER JOIN TableB
ON TableA.name = TableB.name
Sample output:
id name id name
-- ---- -- ----
1 Pirate 2 Pirate
2 Monkey null null
3 Ninja 4 Ninja
4 Spaghetti null null
Left outer join
produces a complete set of records from Table A, with the matching records (where available) in Table B. If there is no match, the right side will contain null
For any field from an outer joined table used in the where clause you must also permit an IS NULL option for that same field, otherwise you negate the effect of the outer join and the result is the same as if you had used an inner join.
SELECT
*
FROM bcharge charge
LEFT OUTER JOIN chgHist history
ON charge.key1 = history.key1
AND charge.key2 = history.key2
AND charge.key3 = history.key3
AND charge.chargeType = history.chargeType
WHERE charge.chargeType = '2'
AND (
(charge.value <> history.value OR history.value IS NULL)
OR
(charge.date <> history.date OR history.date IS NULL)
)
ORDER BY
key1, key2, key3
Edit: Appears that this is the same query structure used by Rene above, so treat this one as in support of that please.
I have a query as below
select --------
from table a
left outer join ....c
where
(a.column='123') and (c.column='456')
I would like to
include "(c.column='456')" only when (a.column='123') is not null
how do I do that in a single query ? or do I need to write two separate queries ?
Should be pretty straightforward :
select --------
from table
left outer join....
where (Condition A IS NULL) OR (condition A AND condition B)
UPDATED: For your conditions:
where (a.column is null) or (a.column='123' and c.column='456')
It will include a a row if it's a.column is null or if bot a.column and c.column have valid values.
As I understand your requirement this is the sql you want
select distinct cm.credit_amt,e.credit_lifetime,e.credit_desc,e.icom_code,e.entry_hint,
e.credit_id,e.credit_type_id,e.recontract_period,a.class_desc,a.offer_id,
a.offer_class_id
from rti_retention.package a
left outer join rti_retention.offer_class_credit b on (a.offer_id=b.offer_id
and a.offer_class_id=b.offer_class_id
and a.customer_type_id=b.customer_type_id)
left outer join rti_retention.credit_pre_bundle c on (b.credit_id=c.credit_id)
left outer join rti_retention.credit e on (c.credit_id=e.credit_id)
left outer join rti_retention.credit_mix_amount cm on (cm.credit_id=c.credit_id and cm.prod_mix_id=a.prod_mix_id)
where a.offer_class_id not in (1,2,16)
and a.channel_id=5 and a.customer_type_id=1
and a.offer_id='6055'
and c.prod_mix_id = case when (select count(*)
from rti_retention.credit_pre_bundle c1
where c1.prod_mix_id='1000' ) > 1 then '1000' else c.prod_mix_id end
and e.icom_code is not null
some time there will be some sql syntax errors. due to i havent full data base i wrote sql on mind. cant test it.