I'm trying to optimize a particular query
I tried with hash tables but the performance didn't improved so much
I need to join the same table three times - pratichesteps - and then finally join with - pratiche - table
This is the query
SELECT DISTINCT dbo.PRATICHESTEPS.IDPraticaStep AS IDPraticaEsame,
PRATICHESTEPS_3.IDPraticaStep AS IDPraticaCatena,
dbo.PRATICHE.IDSysStato AS IDStatoCatena,
dbo.PRATICHE.IDPraticaAccorpata,
PRATICHESTEPS_3.IDAnalisiStep,
dbo.PRATICHE.IDTipoAtto,
PRATICHESTEPS_3.Accorpamento,
dbo.PRATICHE.DataRegistrazione,
PRATICHESTEPS_3.LastStep
FROM dbo.PRATICHESTEPS
INNER JOIN dbo.PRATICHESTEPS AS PRATICHESTEPS_1
ON dbo.PRATICHESTEPS.IDPraticaCarico = PRATICHESTEPS_1.IDPraticaCarico
INNER JOIN dbo.PRATICHESTEPS AS PRATICHESTEPS_2
ON PRATICHESTEPS_1.IDPraticaStep = PRATICHESTEPS_2.IDPraticaStep
INNER JOIN dbo.PRATICHESTEPS AS PRATICHESTEPS_3
ON PRATICHESTEPS_2.IDPraticaCarico = PRATICHESTEPS_3.IDPraticaCarico
INNER JOIN dbo.PRATICHE
ON PRATICHESTEPS_3.IDPraticaStep = dbo.PRATICHE.IDPratica
Related
How improve this query performance second table CustomerAccountBrand inner join
taking long time. I have added Non clustered index that is not use. Is this is split two inner join after that able concatenate?. Please any one help to get that data.
SELECT DISTINCT
RA.AccountNumber,
RA.ShipTo,
RA.SystemCode,
CAB.BrandCode
FROM dbo.CustomerAccountRelatedAccounts RA -- Views
INNER JOIN dbo.CustomerAccount CA
ON RA.RelatedAccountNumber = CA.AccountNumber
AND RA.RelatedShipTo = CA.ShipTo
AND RA.RelatedSystemCode = CA.SystemCode
INNER JOIN dbo.CustomerAccountBrand CAB ---- Taking long time 4:30 mins
ON CA.AccountNumber = CAB.AccountNumber
AND CA.ShipTo = CAB.ShipTo
AND CA.SystemCode = CAB.SystemCode
ALTER VIEW [dbo].[CustomerAccountRelatedAccounts]
AS
SELECT
ca.AccountNumber, ca.ShipTo, ca.SystemCode, cafg.AccountNumber AS RelatedAccountNumber, cafg.ShipTo AS RelatedShipTo,
cafg.SystemCode AS RelatedSystemCode
FROM dbo.CustomerAccount AS ca
LEFT OUTER JOIN dbo.CustomerAccount AS cafg
ON ca.FinancialGroup = cafg.FinancialGroup
AND ca.NationalAccount = cafg.NationalAccount
AND cafg.IsActive = 1
WHERE CA.IsActive = 1
From my experience, the SQL server query optimizer often fails to pick the correct join algorithm when queries become more complex (e.g. joining with your view means that there's no index readily available to join on). If that's what's happening here, then the easy fix is to add a join hint to turn it into a hash join:
SELECT DISTINCT
RA.AccountNumber,
RA.ShipTo,
RA.SystemCode,
CAB.BrandCode
FROM dbo.CustomerAccountRelatedAccounts RA -- Views
INNER JOIN dbo.CustomerAccount CA
ON RA.RelatedAccountNumber = CA.AccountNumber
AND RA.RelatedShipTo = CA.ShipTo
AND RA.RelatedSystemCode = CA.SystemCode
INNER HASH JOIN dbo.CustomerAccountBrand CAB ---- Note the "HASH" keyword
ON CA.AccountNumber = CAB.AccountNumber
AND CA.ShipTo = CAB.ShipTo
AND CA.SystemCode = CAB.SystemCode
My current query show the data from the table called "Buque" and has some references from another tables. The problem is when i execute the query it never shows the result because it consumes too much memory i guess.
The current query i have
select buq.buq_codigo, tbu.tbu_codigo, tbu.tbu_nombre, pai.pai_codigo, pai.pai_nombre,
pue.pto_codigo, pue.pto_nombre, lin.lin_codigo, lin.lin_nombre, tra.tra_codigo,
tra.tra_nombre, buq.buq_nombre, buq.buq_des, buq.num_trb, buq.num_eslora,
buq.max_tons, buq.reg_lloyd, buq.buq_codigo1, buq.codigo_omi,
case buq.buq_estado when 'A' then 'Activo' else 'Inactivo' end as buq_estado
from publico.mae_buque as buq, publico.mae_tipbuque as tbu, publico.mae_pais as pai,
publico.mae_puerto as pue, publico.mae_linea as lin, publico.mae_trafico as tra
where buq.tbu_codigo = tbu.tbu_codigo or
buq.pai_codigo = pai.pai_codigo or
buq.pto_codigo = pue.pto_codigo or
buq.lin_codigo = lin.lin_codigo or
buq.tra_codigo = tra.tra_codigo
I also tried with inner joins but the problem is it returns me the data that meets the conditions of the joins. In other words, if the join has data to compare, returns the name, if not, show the null data.
The query must return me 611 records, with inner joins returns 68 records.
Concerning your desired result, use left outer joins, which fill up any non-existing rows of the right hand side table with null-values;
Concerning the out of memory issue, note that you used or to connect your tables; this actually leads to the fact that almost every record of the involved tables is connected to almost every other record (almost a cross join / cartesian product); This can get very large if you connect 6 tables...
select buq.buq_codigo, tbu.tbu_codigo, tbu.tbu_nombre, pai.pai_codigo, pai.pai_nombre,
pue.pto_codigo, pue.pto_nombre, lin.lin_codigo, lin.lin_nombre, tra.tra_codigo,
tra.tra_nombre, buq.buq_nombre, buq.buq_des, buq.num_trb, buq.num_eslora,
buq.max_tons, buq.reg_lloyd, buq.buq_codigo1, buq.codigo_omi,
case buq.buq_estado when 'A' then 'Activo' else 'Inactivo' end as buq_estado
from publico.mae_buque as buq
left outer join publico.mae_tipbuque as tbu on buq.tbu_codigo = tbu.tbu_codigo
left outer join publico.mae_pais as pai on (buq.pai_codigo = pai.pai_codigo)
left outer join publico.mae_puerto as pue on (buq.pto_codigo = pue.pto_codigo)
left outer join publico.mae_linea as lin on (buq.lin_codigo = lin.lin_codigo)
left outer join publico.mae_trafico as tra on (buq.tra_codigo = tra.tra_codigo)
You have to use left outer join:
select *
from
publico.mae_buque as buq
left outer join publico.mae_tipbuque as tbu on (buq.tbu_codigo = tbu.tbu_codigo)
left outer join publico.mae_pais as pai on (buq.pai_codigo = pai.pai_codigo)
left outer join publico.mae_puerto as pue on (buq.pto_codigo = pue.pto_codigo )
left outer join publico.mae_linea as lin on (buq.lin_codigo = lin.lin_codigo)
left outer join publico.mae_trafico as tra on (buq.tra_codigo = tra.tra_codigo);
I'm working with an Oracle database for the first time and stumbled upon another problem again. When I want to select all the rows in a table with some JOINS I only get the first 350 rows of about 15.000 rows.
Anyone know if there is a set limit somewhere I'm not aware of?
Below is my query if needed:
SELECT orders.plant, orders.workcenter, workcenters.occupied,
workcenters.section, workcentersections.section, orders.capacitycat,
orders.week, orders.earlieststartdate, orders.lateststartdate,
orders.useropstatus, orders.programstatus, orders.reqhours,
orders.finishdate, orders.reqquantity, orders.material, parts.TYPE,
parttypes.TYPE, orders.ordernumber, orders.operation,
orders.preoperation, orders.seqoperation, orders.projectcode,
orders.queuetime, orders.hoursworked, orders.operationtext,
orders.shorttext
FROM (((orders INNER JOIN workcenters ON orders.workcenter =
workcenters.code)
INNER JOIN
workcentersections ON workcenters.section = workcentersections.ID)
INNER JOIN
parts ON orders.material = parts.material)
INNER JOIN
parttypes ON parts.TYPE = parttypes.ID
Assuming your ORDERS table contains 15000 rows and your original query returns only 350 rows, you can replace your (INNER) JOINs with OUTER JOINs:
SELECT orders.plant, orders.workcenter, workcenters.occupied,
workcenters.section, workcentersections.section, orders.capacitycat,
orders.week, orders.earlieststartdate, orders.lateststartdate,
orders.useropstatus, orders.programstatus, orders.reqhours,
orders.finishdate, orders.reqquantity, orders.material, parts.TYPE,
parttypes.TYPE, orders.ordernumber, orders.operation,
orders.preoperation, orders.seqoperation, orders.projectcode,
orders.queuetime, orders.hoursworked, orders.operationtext,
orders.shorttext
FROM orders
LEFT OUTER JOIN workcenters ON orders.workcenter = workcenters.code
LEFT OUTER JOIN workcentersections
ON workcenters.section = workcentersections.ID
LEFT OUTER JOIN parts ON orders.material = parts.material
LEFT OUTER JOIN parttypes ON parts.TYPE = parttypes.ID
This will give you all rows from ORDERS (you might get duplicates if you haven't got strict 1:N relationships).
Then, you should replace the LEFT OUTER JOINs one-by-one with INNER JOINs and check the row count of each of these modified queries to find out which of the JOINs is responsible for the missing data.
I have been using Oracle SQL for around 6 months so still a beginner. I need to query the database to get information on all items on a particular order (order number is via $_GET['id']).
I have come up with the below query, it works as expected and as I need but I do not know whether I am over complicating things which would slow the query down at all. I understand there are a number of ways to do a single thing and there may be better methods to write this query since I am a beginner.
I am using Oracle 8i (due to this is the version an application we use is supplied with) so I believe that some JOIN etc. are not available in this version, but is there a better way to write a query such as the below?
SELECT auf_pos.auf_pos,
(SELECT auf_stat.anz
FROM auf_stat
WHERE auf_stat.auf_pos = auf_pos.auf_pos
AND auf_stat.auf_nr = ".$_GET['id']."),
(SELECT auf_text.zl_str
FROM auf_text
WHERE auf_text.zl_mod = 0
AND auf_text.auf_pos = auf_pos.auf_pos
AND auf_text.auf_nr = ".$_GET['id']."),
(SELECT glas_daten_basis.gl_bez
FROM glas_daten_basis
WHERE glas_daten_basis.idnr = auf_pos.glas1),
(SELECT lzr_daten.lzr_breite
FROM lzr_daten
WHERE lzr_daten.lzr_idnr = auf_pos.lzr1),
(SELECT glas_daten_basis.gl_bez
FROM glas_daten_basis
WHERE glas_daten_basis.idnr = auf_pos.glas2),
auf_pos.breite,
auf_pos.hoehe,
auf_pos.spr_jn
FROM auf_pos
WHERE auf_pos.auf_nr = ".$_GET['id']."
Thanks in advance to any Oracle gurus that could help this beginner out!
You could rewrite it using joins. If your subselects aren't expected to return any NULL values, then you can use INNER JOINS:
SELECT auf_pos.auf_pos,
auf_stat.anz,
auf_text.zl_str,
glas_daten_basis.gl_bez,
lzr_daten.lzr_breite,
glas_daten_basis.gl_bez,
auf_pos.breite,
auf_pos.hoehe,
auf_pos.spr_jn
FROM auf_pos
INNER JOIN auf_stat ON auf_stat.auf_pos = auf_pos.auf_pos AND auf_stat.auf_nr = ".$_GET['id'].")
INNER JOIN auf_text ON auf_text.zl_mod = 0 AND auf_text.auf_pos = auf_pos.auf_pos AND auf_text.auf_nr = ".$_GET['id'].")
INNER JOIN glas_daten_basis ON glas_daten_basis.idnr = auf_pos.glas1
INNER JOIN lzr_daten ON lzr_daten.lzr_idnr = auf_pos.lzr1
INNER JOIN glas_daten_basis ON glas_daten_basis.idnr = auf_pos.glas2
Or if there are cases where you wouldn't have matches on all the tables, you could replace the INNER joins with LEFT OUTER joins:
SELECT auf_pos.auf_pos,
auf_stat.anz,
auf_text.zl_str,
glas_daten_basis.gl_bez,
lzr_daten.lzr_breite,
glas_daten_basis.gl_bez,
auf_pos.breite,
auf_pos.hoehe,
auf_pos.spr_jn
FROM auf_pos
LEFT OUTER JOIN auf_stat ON auf_stat.auf_pos = auf_pos.auf_pos AND auf_stat.auf_nr = ".$_GET['id'].")
LEFT OUTER JOIN auf_text ON auf_text.zl_mod = 0 AND auf_text.auf_pos = auf_pos.auf_pos AND auf_text.auf_nr = ".$_GET['id'].")
LEFT OUTER JOIN glas_daten_basis ON glas_daten_basis.idnr = auf_pos.glas1
LEFT OUTER JOIN lzr_daten ON lzr_daten.lzr_idnr = auf_pos.lzr1
LEFT OUTER JOIN glas_daten_basis ON glas_daten_basis.idnr = auf_pos.glas2
Whether or not you see any performance gains is debatable. As I understand it, the Oracle query optimizer should take your query and execute it with a similar plan to the join queries, but this is dependent on a number of factors, so the best thing to do it give it a try..
I am trying to execute the following sql query but it takes 22 seconds to execute. the number of returned items is 554192. I need to make this faster and have already put indexes in all the tables involved.
SELECT mc.name AS MediaName,
lcc.name AS Country,
i.overridedate AS Date,
oi.rating,
bl1.firstname + ' ' + bl1.surname AS Byline,
b.id BatchNo,
i.numinbatch ItemNumberInBatch,
bah.changedatutc AS BatchDate,
pri.code AS IssueNo,
pri.name AS Issue,
lm.neptunemessageid AS MessageNo,
lmt.name AS MessageType,
bl2.firstname + ' ' + bl2.surname AS SourceFullName,
lst.name AS SourceTypeDesc
FROM profiles P
INNER JOIN profileresults PR
ON P.id = PR.profileid
INNER JOIN items i
ON PR.itemid = I.id
INNER JOIN batches b
ON b.id = i.batchid
INNER JOIN itemorganisations oi
ON i.id = oi.itemid
INNER JOIN lookup_mediachannels mc
ON i.mediachannelid = mc.id
LEFT OUTER JOIN lookup_cities lc
ON lc.id = mc.cityid
LEFT OUTER JOIN lookup_countries lcc
ON lcc.id = mc.countryid
LEFT OUTER JOIN itembylines ib
ON ib.itemid = i.id
LEFT OUTER JOIN bylines bl1
ON bl1.id = ib.bylineid
LEFT OUTER JOIN batchactionhistory bah
ON b.id = bah.batchid
INNER JOIN itemorganisationissues ioi
ON ioi.itemorganisationid = oi.id
INNER JOIN projectissues pri
ON pri.id = ioi.issueid
LEFT OUTER JOIN itemorganisationmessages iom
ON iom.itemorganisationid = oi.id
LEFT OUTER JOIN lookup_messages lm
ON iom.messageid = lm.id
LEFT OUTER JOIN lookup_messagetypes lmt
ON lmt.id = lm.messagetypeid
LEFT OUTER JOIN itemorganisationsources ios
ON ios.itemorganisationid = oi.id
LEFT OUTER JOIN bylines bl2
ON bl2.id = ios.bylineid
LEFT OUTER JOIN lookup_sourcetypes lst
ON lst.id = ios.sourcetypeid
WHERE p.id = #profileID
AND b.statusid IN ( 6, 7 )
AND bah.batchactionid = 6
AND i.statusid = 2
AND i.isrelevant = 1
when looking at the execution plan I can see an step which is costing 42%. Is there any way I could get this to a lower threshold or any way that I can improve the performance of the whole query.
Remove the profiles table as it is not needed and change the WHERE clause to
WHERE PR.profileid = #profileID
You have a left outer join on the batchactionhistory table but also have a condition in your WHERE clause which turns it back into an inner join. Change you code to this:
LEFT OUTER JOIN batchactionhistory bah
ON b.id = bah.batchid
AND bah.batchactionid = 6
You don't need the batches table as it is used to join other tables which could be joined directly and to show the id in you SELECT which is also available in other tables. Make the following changes:
i.batchidid AS BatchNo,
LEFT OUTER JOIN batchactionhistory bah
ON i.batchidid = bah.batchid
Are any of the fields that are used in joins or the WHERE clause from tables that contain large amounts of data but are not indexed. If so try adding an index on at time to the largest table.
Do you need every field in the result - if you could loose one or to you maybe could reduce the number of tables further.
First, if this is not a stored procedure, make it one. That's a lot of text for sql server to complile.
Next, my experience is that "worst practices" are occasionally a good idea. Specifically, I have been able to improve performance by splitting large queries into a couple or three small ones and assembling the results.
If this query is associated with a .net, coldfusion, java, etc application, you might be able to do the split/re-assemble in your application code. If not, a temporary table might come in handy.