My query is working but it takes time to display the data. Can you help me to make it quick.
$sql="SELECT allinvty3.*, stock_transfer_tb.* from stock_transfer_tb
INNER JOIN allinvty3 on stock_transfer_tb.in_code = allinvty3.in_code
where stock_transfer_tb.in_code NOT IN (SELECT barcode.itemcode from barcode where stock_transfer_tb.refnumber = barcode.refitem)";
I would recommend using the following query:
SELECT
a.*,
s.*
FROM stock_transfer_tb s
INNER JOIN allinvty3 a
ON s.in_code = a.in_code
WHERE
NOT EXISTS (SELECT 1 FROM barcode b
WHERE s.refnumber = b.refitem AND s.in_code = b.itemcode);
If this still doesn't give you the performance you want, then you should look into adding indices on all columns involved in the join and where clause.
Related
I have a working PostgreSQL query, but it is taking a considerable amount of time to execute. I need help optimising it.
I have:
Removed inner queries as much as possible.
Removed the unnecessary data from the query.
Created a with query which gets the required data from the beginning
I need help to optimise this query
with data as (
select
e.id,
e.name,
t.barcode,
tt.variant,
t.cost_cents::decimal / 100 as ticket_cost,
t.fee_cents::decimal / 100 as booking_fee
from
tickets t
inner join events e on t.event_id = e.id
inner join ticket_types tt on t.ticket_type_id = tt.id
where
t.status = 2
and e.source in ('source1', 'source2')
)
select
d.name,
count(distinct d.barcode) as issued,
(select count(distinct d2.barcode) from data d2 where d2.id = d.id and d2.variant is null) as sold,
sum(d.ticket_cost) as ticket_revenue,
sum(d.booking_fee) as booking_fees
from
data d
group by
id,
name
Better to detect slow parts with using EXPLAIN .
It will show cost of all parts
You can speed up joins by creating proper indexes.
Also, remove the subquery
(select count(distinct d2.barcode) from data d2 where d2.id = d.id and d2.variant is null)
from the SELECT clause and add a join to d2 table something like this:
select
d.name,
count(distinct d.barcode) as issued,
count(distinct d2.barcode) as sold,
sum(d.ticket_cost) as ticket_revenue,
sum(d.booking_fee) as booking_fees
from
data d
left join data d2 on (d2.id = d.id and d2.variant is null)
group by
d.id,
d.name
I have a query of the following, basic form.
SELECT DISTINCT
a.field1,
b.field2,
c.agg_values
FROM a
INNER JOIN b ON a.something = b.something
LEFT JOIN (
SELECT
array_to_string(array_agg(label), ';;') AS agg_values,
some_table.some_field
FROM some_table
WHERE some_table.some_field = 'some-fixed-value'
GROUP BY some_field
) AS c ON a.some_field = c.some_field
WHERE a.some_other_field = 'some-other-fixed-value'
There's nothing too wild about this query. Pretty run of the mill!
This query runs pretty slow in my Postgres 9.4.5 (~4 minutes), where I have maybe 15k records returned total. some_table has probably ~10k records.
If I move the content of that LEFT JOIN sub-query to a temp table and left join from the temp table, my performance increases substantially. My query may take only 15s now, vs 240s. To be more explicit, if I remove SELECT array_to_string ... GROUP BY some_field query, and put that query into a temp table, then left join on that temp table, BAM, fast.
CREATE TEMP TABLE temp_table_c ( ... );
INSERT INTO temp_table_c SELECT ... same query nested in LEFT JOIN from before ...;
SELECT DISTINCT
a.field1,
b.field2,
c.agg_values
FROM a
INNER JOIN ON a.something = b.something
LEFT JOIN temp_table_c AS c ON a.some_field = c.some_field
WHERE a.some_other_field = 'some-other-fixed-value'
I would appreciate it if someone could explain why the TEMP TABLE version of the query is so much more performant.
Thanks!
In SQL Server, I know for sure that the following query;
SELECT things.*
FROM things
LEFT OUTER JOIN (
SELECT thingreadings.thingid, reading
FROM thingreadings
INNER JOIN things on thingreadings.thingid = things.id
ORDER BY reading DESC LIMIT 1) AS readings
ON things.id = readings.thingid
WHERE things.id = '1'
Would join against thingreadings only once the WHERE id = 1 had restricted the record set down. It left joins against just one row. However in order for performance to be acceptable in postgres, I have to add the WHERE id= 1 to the INNER JOIN things on thingreadings.thingid = things.id line too.
This isn't ideal; is it possible to force postgres to know that what I am joining against is only one row without explicitly adding the WHERE clauses everywhere?
An example of this problem can be seen here;
I am trying to recreate the following query in a more efficient way;
SELECT things.id, things.name,
(SELECT thingreadings.id FROM thingreadings WHERE thingid = things.id ORDER BY id DESC LIMIT 1),
(SELECT thingreadings.reading FROM thingreadings WHERE thingid = things.id ORDER BY id DESC LIMIT 1)
FROM things
WHERE id IN (1,2)
http://sqlfiddle.com/#!15/a172c/2
Not really sure why you did all that work. Isn't the inner query enough?
SELECT t.*
FROM thingreadings tr
INNER JOIN things t on tr.thingid = t.id AND t.id = '1'
ORDER BY tr.reading DESC
LIMIT 1;
sqlfiddle demo
When you want to select the latest value for each thingID, you can do:
SELECT t.*,a.reading
FROM things t
INNER JOIN (
SELECT t1.*
FROM thingreadings t1
LEFT JOIN thingreadings t2
ON (t1.thingid = t2.thingid AND t1.reading < t2.reading)
WHERE t2.thingid IS NULL
) a ON a.thingid = t.id
sqlfiddle demo
The derived table gets you the record with the most recent reading, then the JOIN gets you the information from things table for that record.
The where clause in SQL applies to the result set you're requesting, NOT to the join.
What your code is NOT saying: "do this join only for the ID of 1"...
What your code IS saying: "do this join, then pull records out of it where the ID is 1"...
This is why you need the inner where clause. Incidentally, I also think Filipe is right about the unnecessary code.
I manage to do the selection with more selects and a loop. 4 tables ( the last one was just for collecting all the data )
But now i'm thinking of a way to select all the fields i need with just one select statement. Here is the huge select :)
SELECT vbak~vbeln vbak~audat
tvakt~bezei
vbap~posnr vbap~matnr vbap~kwmeng vbap~vrkme
lips~vbeln lips~posnr lips~werks lips~lfimg
vbfa~vbtyp_n
FROM vbak JOIN vbap ON vbak~vbeln = vbap~vbeln
JOIN tvakt ON vbak~auart = tvakt~auart
LEFT JOIN vbfa ON vbfa~vbelv = vbak~vbeln AND vbfa~posnv = vbap~posnr
JOIN lips ON vbfa~vbeln = lips~vbeln AND vbfa~posnn = lips~posnr
INTO TABLE gt_salord
WHERE tvakt~spras = 'EN' AND
vbak~vbeln IN s_vbeln AND
vbak~audat IN s_audat.
The problem is this doesn't work. When i try to activate it throws this error: " Unable to compare with "VBAP~POSNR". A table can be joined with a maximum of one other table using LEFT OUTER JOIN "
If i don't use LEFT JOIN and only JOIN it works but i don't get all what i want. I need to get all the SALES ORDERS even if they don't have a DELIVERY ORDER assigned. Is there a way to do that, or do i really have to split my select?
I have noticed in SAP that it's more efficient to simplify select statements and proceed with LOOP and SELECT SINGLE for table that do not participate in data selection.
In your case data from table VBFA could be fetch after data selection (it is not restricting the amount of data fetched from the DB).
Of course it depends on indexes, application server buffering... but, even though it might be counter-intuitive for SQL experts, keeping select statements not too complex in SAP is best.
Can you try the following selection:
SELECT vbak~vbeln vbak~audat
tvakt~bezei
vbap~posnr vbap~matnr vbap~kwmeng vbap~vrkme
lips~vbeln lips~posnr lips~werks lips~lfimg
vbfa~vbtyp_n
FROM vbak JOIN vbap ON vbak~vbeln = vbap~vbeln
JOIN tvakt ON vbak~auart = tvakt~auart
LEFT JOIN vbfa ON vbfa~vbelv = vbap~vbeln AND vbfa~posnv = vbap~posnr
JOIN lips ON vbfa~vbeln = lips~vbeln AND vbfa~posnn = lips~posnr
INTO TABLE gt_salord
WHERE tvakt~spras = 'EN' AND
vbak~vbeln IN s_vbeln AND
vbak~audat IN s_audat.
I can't test the result, but the syntax check say: ok.
There is only one tiny difference:
x---- difference
v
LEFT JOIN vbfa ON vbfa~vbelv = vbap~vbeln AND vbfa~posnv = vbap~posnr
LEFT JOIN vbfa ON vbfa~vbelv = vbak~vbeln AND vbfa~posnv = vbap~posnr
You compared vbfa~vbelv with vbak~vbeln, I do it with vbap~vbeln. Both have the same value, but in the on-clause you use again vbap.
I dont know about SAP Abap . But from SQL point of view you can use derived query if it is supported in SAP.
here is some approach :
select * from
(
select * from
table1 inner join table2 on table1.key=table2.key
inner join table3 on table1.key=table3.key
) a left outer join table4 b
on a.key=b.key
Posting this as the question is tagged as SQL. Hope it works
Try to change the order of table fields in the on clause of left join. Put vbap~vbeln = vbfa~vbelv
Basically I have this cursor that was not written by me but is taking some time to process and I was wanting to try and improve it by getting rid of the cursor all together.
Here is the code:
DECLARE #class_id int, #title_code varchar(30)
DECLARE title_class CURSOR FOR
SELECT DISTINCT title_code FROM tmp_business_class_titles (NOLOCK)
OPEN title_class
FETCH title_class INTO #title_code
WHILE ##FETCH_STATUS = 0
BEGIN
SELECT TOP 1 #class_id = bc1.categoryid
FROM tmp_business_class_titles bct,
dbo.Categories bc1 (nolock)
join dbo.Categories bc2 (nolock) on bc2.categoryid = bc1.highercategoryid
join dbo.Categories bc3 (nolock) on bc3.categoryid = bc2.highercategoryid
WHERE bc1.categoryid = bct.class_id
AND title_code = #title_code
ORDER BY Default_Flag DESC
UPDATE products
SET subcategoryid = #class_id
WHERE ccode = #title_code
AND spdisplaytype = 'Table'
UPDATE products
SET subcategoryid = #class_id
WHERE highercatalogid IN (
SELECT catalogid FROM products (nolock)
WHERE ccode = #title_code AND spdisplaytype = 'Table')
FETCH title_class INTO #title_code
END
CLOSE title_class
DEALLOCATE title_class
The table tmp_business_class_titles looks like this:
class_id,title_code,Default_flag
7,101WGA,0
7,10315,0
29,8600,0
The default flag can always be 0 but if it is 1 then the logic should automatically pick the default class_id for that title_id.
So the current logic loops through the above table in a cursor and then selects the top 1 class id for each title, ordered by the the default flag (so the class_id with a default_flag of 1 should always be returned first.) and applies the default class_id to the products table.
This code takes around 1:20 to run and I am trying to convert this into one or 2 update statements but I have exhausted my brain in doing so.
Any TSQL Guru's have any ideas if this is possible or should I re-evaluate the entire logic on how the default flag works?
cheers for any help.
I don't have quite enough information to work with, so the following query is likely to fail. I particularly need more information on the products table to make this work, but assuming that you have SQL Server 2005 or higher, this might be enough to get you started in the right direction. It utilizes common table expressions along with the RANK function. I highly recommend learning about them, and in all likelihood, it will greatly improve the efficiency of the query.
;WITH cteTitle As (
SELECT
sequence = RANK() OVER (PARTITION BY bct.title_code ORDER BY Default_Flag desc)
,bct.title_code
,bc1.categoryid
FROM
tmp_business_class_titles bct
join Categories bc1 ON bc1.categoryid = bct.class_id
join Categories bc2 ON bc2.categoryid = bc1.highercategoryid
join Categories bc3 ON bc3.categoryid = bc2.highercategoryid
)
UPDATE
prod
SET
subcategoryid = ISNULL(t.categoryid,t2.categoryid)
FROM
products prod
LEFT join products subprod ON subprod.catalogid = prod.highercatalogid
LEFT join cteTitle t ON prod.ccode = t.title_code AND t.sequence = 1 AND prod.spdisplaytype = 'Table'
LEFT join cteTitle t2 ON subprod.ccode = t2.title_code And t2.sequence = 1 AND subprod.spdisplaytype = 'Table'
WHERE
t2.categoryid IS NOT NULL