Suppose I have this query
SELECT * FROM (
SELECT * FROM table_a
WHERE id > 10 )
AS a_results LEFT JOIN
(SELECT * from table_b
WHERE id IN
(SElECT id FROM a_results)
ON (a_results.id = b_results.id)
I would get the error "a_results is not a table". Anywhere I could use the re-use the results of the subquery?
Edit: It has been noted that this query doesn't make sense...it doesn't, yes. This is just to illustrate the question which I am asking; the 'real' query actually looks something like this:
SELECT SQL_CALC_FOUND_ROWS * FROM
( SELECT wp_pod_tbl_hotel . *
FROM wp_pod_tbl_hotel, wp_pod_rel, wp_pod
WHERE wp_pod_rel.field_id =12
AND wp_pod_rel.tbl_row_id =1
AND wp_pod.tbl_row_id = wp_pod_tbl_hotel.id
AND wp_pod_rel.pod_id = wp_pod.id
) as
found_hotel LEFT JOIN (
SELECT COUNT(*) as review_count, avg( (
location_rating + staff_performance_rating + condition_rating + room_comfort_rating + food_rating + value_rating
) /6 ) AS average_score, hotelid
FROM (
SELECT r. * , wp_pod_rel.tbl_row_id AS hotelid
FROM wp_pod_tbl_review r, wp_pod_rel, wp_pod
WHERE wp_pod_rel.field_id =11
AND wp_pod_rel.pod_id = wp_pod.id
AND r.id = wp_pod.tbl_row_id
AND wp_pod_rel.tbl_row_id
IN (
SELECT wp_pod_tbl_hotel .id
FROM wp_pod_tbl_hotel, wp_pod_rel, wp_pod
WHERE wp_pod_rel.field_id =12
AND wp_pod_rel.tbl_row_id =1
AND wp_pod.tbl_row_id = wp_pod_tbl_hotel.id
AND wp_pod_rel.pod_id = wp_pod.id
)
) AS hotel_reviews
GROUP BY hotel_reviews.hotelid
ORDER BY average_score DESC
AS sorted_hotel ON (id = sorted_hotel.hotelid)
As you can see, the sub-query which makes up the found_query table is repeated elsewhere downward as another sub-query, so I was hoping to re-use the results
You can not use a sub-query like this.
I'm not sure I understand your query, but wouldn't that be sufficient?
SELECT * FROM table_a a
LEFT JOIN table_b b ON ( b.id = a.id )
WHERE a.id > 10
It would return all rows from table_a where id > 10 and LEFT JOIN rows from table_b where id matches.
Related
I'm currently trying to find the percentage of certain amount of preregistered users in my postgres db, the operation would be (1185 * 100) / 3104 = 38.17. To do that I'm using two select statements to retrieve each count, but I've been unable to operate between them:
+ count +
- 1185 -
- 3104 -
This is what I have:
select
count(*)
from crm_user_preregistred
left join crm_player on crm_user_preregistred."document" = crm_player."document"
left join crm_user on crm_player.user_id = crm_user.id
where crm_user.email is not null
union all
select
count(*)
from crm_user_preregistred
Thanks in advance for any hint or help.
you can use some with clause to simplifie your selects, substitute the values with your count(*) selects, maybe some formating to the result, and a check for 0 on value2
with temp_value1 as (
select 1185 as value1 ),
temp_value2 as (
select 3104 as value2 )
select (select temp_value1.value1::float * 100 from temp_value1) /
(select temp_value2.value2::float from temp_value2)
result :
38.17654639175258
with your selects:
with temp_value1 as (
select
count(*) as value1
from crm_user_preregistred
left join crm_player on crm_user_preregistred."document" = crm_player."document"
left join crm_user on crm_player.user_id = crm_user.id
where crm_user.email is not null
),
temp_value2 as (
select
count(*) as value2
from crm_user_preregistred
)
select (select temp_value1.value1::float * 100 from temp_value1) / (select temp_value2.value2::float from temp_value2)
You can do this in one query:
select count(*) filter (where cu.email is not null) * 100.0 / max(cup.cnt)
from (select cup.*, count(*) over () as cnt
from crm_user_preregistred cup
) cup left join
crm_player cp
on cup."document" = cp."document" left join
crm_user cu
on cp.user_id = cu.id
where cu.email is not null;
I suspect that the query could be simplified further, but without knowing your data model, it is hard to make specific suggestions.
The following script is very slow when its run.
I have no idea how to improve the performance of the script.
Even with a view takes more than quite a lot minutes.
Any idea please share to me.
SELECT DISTINCT
( id )
FROM ( SELECT DISTINCT
ct.id AS id
FROM [Customer].[dbo].[Contact] ct
LEFT JOIN [Customer].[dbo].[Customer_ids] hnci ON ct.id = hnci.contact_id
WHERE hnci.customer_id IN (
SELECT DISTINCT
( [Customer_ID] )
FROM [Transactions].[dbo].[Transaction_Header]
WHERE actual_transaction_date > '20120218' )
UNION
SELECT DISTINCT
contact_id AS id
FROM [Customer].[dbo].[Restaurant_Attendance]
WHERE ( created > '2012-02-18 00:00:00.000'
OR modified > '2012-02-18 00:00:00.000'
)
AND ( [Fifth_Floor_London] = 1
OR [Fourth_Floor_Leeds] = 1
OR [Second_Floor_Bristol] = 1
)
UNION
SELECT DISTINCT
( ct.id )
FROM [Customer].[dbo].[Contact] ct
INNER JOIN [Customer].[dbo].[Wifinity_Devices] wfd ON ct.wifinity_uniqueID = wfd.[CustomerUniqueID]
AND startconnection > '2012-02-17'
UNION
SELECT DISTINCT
comdt.id AS id
FROM [Customer].[dbo].[Complete_dataset] comdt
LEFT JOIN [Customer].[dbo].[Aggregate_Spend_Counts] agsc ON comdt.id = agsc.contact_id
WHERE agsc.contact_id IS NULL
AND ( opt_out_Mail <> 1
OR opt_out_email <> 1
OR opt_out_SMS <> 1
OR opt_out_Mail IS NULL
OR opt_out_email IS NULL
OR opt_out_SMS IS NULL
)
AND ( address_1 IS NOT NULL
OR email IS NOT NULL
OR mobile IS NOT NULL
)
UNION
SELECT DISTINCT
( contact_id ) AS id
FROM [Customer].[dbo].[VIP_Card_Holders]
WHERE VIP_Card_number IS NOT NULL
) AS tbl
Wow, where to start...
--this distinct does nothing. Union is already distinct
--SELECT DISTINCT
-- ( id )
--FROM (
SELECT DISTINCT [Customer_ID] as ID
FROM [Transactions].[dbo].[Transaction_Header]
where actual_transaction_date > '20120218' )
UNION
SELECT
contact_id AS id
FROM [Customer].[dbo].[Restaurant_Attendance]
-- not sure that you are getting the date range you want. Should these be >=
-- if you want everything that occurred on the 18th or after you want >= '2012-02-18 00:00:00.000'
-- if you want everything that occurred on the 19th or after you want >= '2012-02-19 00:00:00.000'
-- the way you have it now, you will get everything on the 18th unless it happened exactly at midnight
WHERE ( created > '2012-02-18 00:00:00.000'
OR modified > '2012-02-18 00:00:00.000'
)
AND ( [Fifth_Floor_London] = 1
OR [Fourth_Floor_Leeds] = 1
OR [Second_Floor_Bristol] = 1
)
-- all of this does nothing because we already have every id in the contact table from the first query
-- UNION
-- SELECT
-- ( ct.id )
-- FROM [Customer].[dbo].[Contact] ct
-- INNER JOIN [Customer].[dbo].[Wifinity_Devices] wfd ON ct.wifinity_uniqueID = wfd.[CustomerUniqueID]
-- AND startconnection > '2012-02-17'
UNION
-- cleaned this up with isnull function and coalesce
SELECT
comdt.id AS id
FROM [Customer].[dbo].[Complete_dataset] comdt
LEFT JOIN [Customer].[dbo].[Aggregate_Spend_Counts] agsc ON comdt.id = agsc.contact_id
WHERE agsc.contact_id IS NULL
AND ( isnull(opt_out_Mail,0) <> 1
OR isnull(opt_out_email,0) <> 1
OR isnull(opt_out_SMS,0) <> 1
)
AND coalesce(address_1 , email, mobile) IS NOT NULL
UNION
SELECT
( contact_id ) AS id
FROM [Customer].[dbo].[VIP_Card_Holders]
WHERE VIP_Card_number IS NOT NULL
-- ) AS tbl
Where exists is generally faster than in as well.
Or conditions are generally slower as well, use more union statements instead.
And learn to use left joins correctly. If you have a where condition (other than where id is null) on the table on teh right side of a left join, it will convert to an inner join. If this is not what you want, then your code is currently giving you an incorrect result set.
See http://wiki.lessthandot.com/index.php/WHERE_conditions_on_a_LEFT_JOIN for an explanation of how to fix.
As stated in a comment optimize one at a time. See which one takes the longest and focus on that one.
union will remove duplicates so you don't need the distinct on the individual queries
On you first I would try this:
The left join is killed by the WHERE hnci.customer_id IN so you might as well have a join.
The sub-query is not efficient as cannot use an index on the IN.
The query optimizer does not know what in ( select .. ) will return so it cannot optimize use of indexes.
SELECT ct.id AS id
FROM [Customer].[dbo].[Contact] ct
JOIN [Customer].[dbo].[Customer_ids] hnci
ON ct.id = hnci.contact_id
JOIN [Transactions].[dbo].[Transaction_Header] th
on hnci.customer_id = th.[Customer_ID]
and th.actual_transaction_date > '20120218'
On that second join the query optimizer has the opportunity of which condition to apply first. Let say [Customer].[dbo].[Customer_ids].[customer_id] and [Transactions].[dbo].[Transaction_Header] each have indexes. The query optimizer has the option to apply that before [Transactions].[dbo].[Transaction_Header].[actual_transaction_date].
If [actual_transaction_date] is not indexed then for sure it would do the other ID join first.
With your in ( select ... ) the query optimizer has no option but to apply the actual_transaction_date > '20120218' first. OK some times query optimizer is smart enough to use an index inside the in outside the in but why make it hard for the query optimizer. I have found the query optimizer make better decisions if you make the decisions easier.
A join on a sub-query has the same problem. You take options away from the query optimizer. Give the query optimizer room to breathe.
try this, temptable should help you:
IF OBJECT_ID('Tempdb..#Temp1') IS NOT NULL
DROP TABLE #Temp1
--Low perfomance because of using "WHERE hnci.customer_id IN ( .... ) " - loop join must be
--and this "where" condition will apply to two tables after left join,
--so result will be same as with two inner joints but with bad perfomance
--SELECT DISTINCT
-- ct.id AS id
--INTO #temp1
--FROM [Customer].[dbo].[Contact] ct
-- LEFT JOIN [Customer].[dbo].[Customer_ids] hnci ON ct.id = hnci.contact_id
--WHERE hnci.customer_id IN (
-- SELECT DISTINCT
-- ( [Customer_ID] )
-- FROM [Transactions].[dbo].[Transaction_Header]
-- WHERE actual_transaction_date > '20120218' )
--------------------------------------------------------------------------------
--this will give the same result but with better perfomance then previouse one
--------------------------------------------------------------------------------
SELECT DISTINCT
ct.id AS id
INTO #temp1
FROM [Customer].[dbo].[Contact] ct
JOIN [Customer].[dbo].[Customer_ids] hnci ON ct.id = hnci.contact_id
JOIN ( SELECT DISTINCT
( [Customer_ID] )
FROM [Transactions].[dbo].[Transaction_Header]
WHERE actual_transaction_date > '20120218'
) T ON hnci.customer_id = T.[Customer_ID]
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
INSERT INTO #temp1
( id
)
SELECT DISTINCT
contact_id AS id
FROM [Customer].[dbo].[Restaurant_Attendance]
WHERE ( created > '2012-02-18 00:00:00.000'
OR modified > '2012-02-18 00:00:00.000'
)
AND ( [Fifth_Floor_London] = 1
OR [Fourth_Floor_Leeds] = 1
OR [Second_Floor_Bristol] = 1
)
INSERT INTO #temp1
( id
)
SELECT DISTINCT
( ct.id )
FROM [Customer].[dbo].[Contact] ct
INNER JOIN [Customer].[dbo].[Wifinity_Devices] wfd ON ct.wifinity_uniqueID = wfd.[CustomerUniqueID]
AND startconnection > '2012-02-17'
INSERT INTO #temp1
( id
)
SELECT DISTINCT
comdt.id AS id
FROM [Customer].[dbo].[Complete_dataset] comdt
LEFT JOIN [Customer].[dbo].[Aggregate_Spend_Counts] agsc ON comdt.id = agsc.contact_id
WHERE agsc.contact_id IS NULL
AND ( opt_out_Mail <> 1
OR opt_out_email <> 1
OR opt_out_SMS <> 1
OR opt_out_Mail IS NULL
OR opt_out_email IS NULL
OR opt_out_SMS IS NULL
)
AND ( address_1 IS NOT NULL
OR email IS NOT NULL
OR mobile IS NOT NULL
)
INSERT INTO #temp1
( id
)
SELECT DISTINCT
( contact_id ) AS id
FROM [Customer].[dbo].[VIP_Card_Holders]
WHERE VIP_Card_number IS NOT NULL
SELECT DISTINCT
id
FROM #temp1 AS T
Working (NOT IN) retrieves 3 rows:
select DISTINCT d.* from Device d , Company c3
WHERE d.deviceid NOT IN
(
Select d1.deviceid from Device d1, Clone x1
WHERE d1.deviceid = x1.deviceID
AND
(
x1.XPath = 'hi'
OR x1.XPath = 'bye'
)
AND
(
EXISTS ( select * from (SELECT * FROM [dbo].[Split] ('T130SF0W2050', ',')) as s
WHERE x1.Value like '%' + s.items + '%' )
)
)
AND
d.companyid = c3.companyid and c3.companynumber in (SELECT * FROM [dbo].[Split] ('00223200', ','))
Not Working(not exists):
select DISTINCT d.* from Device d , Company c3
WHERE NOT EXISTS
(Select * from Device d1, Clone x1
WHERE d1.deviceid = x1.deviceID
AND
(
x1.XPath = 'hi'
OR x1.XPath = 'bye'
)
AND
(
EXISTS ( select * from (SELECT * FROM [dbo].[Split] ('T130SF0W2050', ',')) as s
WHERE x1.Value like '%' + s.items + '%' )
)
)
AND
d.companyid = c3.companyid and c3.companynumber in (SELECT * FROM [dbo].[Split] ('00223200', ','))
I'm unsure I'm using the exists syntax correct, what should I select from the subquery? I've tried a few different combinations. It won't run if I put WHERE d.deviceid NOT EXISTS
Solution (thanks to Nikola):
add AND d1.deviceid = d.deviceid inside the Exists subquery.
The difference is that the NOT IN query returns devices that match the company and don't match the inner query specification.
For the NOT EXIST query to work as written (where "work as written" refers to returning the same result as the top query), there can't be any devices that exist matching the inner query. If any devices match the inner query at all, the query won't return any results.
I have a query like this:
SELECT TV.Descrizione as TipoVers,
sum(ImportoVersamento) as ImpTot,
count(*) as N,
month(DataAllibramento) as Mese
FROM PROC_Versamento V
left outer join dbo.PROC_TipoVersamento TV
on V.IDTipoVersamento = TV.IDTipoVersamento
inner join dbo.PROC_PraticaRiscossione PR
on V.IDPraticaRiscossioneAssociata = PR.IDPratica
inner join dbo.DA_Avviso A
on PR.IDDatiAvviso = A.IDAvviso
where DataAllibramento between '2012-09-08' and '2012-09-17' and A.IDFornitura = 4
group by V.IDTipoVersamento,month(DataAllibramento),TV.Descrizione
order by V.IDTipoVersamento,month(DataAllibramento)
This query must always return something. If no result is produced a
0 0 0 0
row must be returned. How can I do this. Use a isnull for every selected field isn't usefull.
Use a derived table with one row and do a outer apply to your other table / query.
Here is a sample with a table variable #T in place of your real table.
declare #T table
(
ID int,
Grp int
)
select isnull(Q.MaxID, 0) as MaxID,
isnull(Q.C, 0) as C
from (select 1) as T(X)
outer apply (
-- Your query goes here
select max(ID) as MaxID,
count(*) as C
from #T
group by Grp
) as Q
order by Q.C -- order by goes to the outer query
That will make sure you have always at least one row in the output.
Something like this using your query.
select isnull(Q.TipoVers, '0') as TipoVers,
isnull(Q.ImpTot, 0) as ImpTot,
isnull(Q.N, 0) as N,
isnull(Q.Mese, 0) as Mese
from (select 1) as T(X)
outer apply (
SELECT TV.Descrizione as TipoVers,
sum(ImportoVersamento) as ImpTot,
count(*) as N,
month(DataAllibramento) as Mese,
V.IDTipoVersamento
FROM PROC_Versamento V
left outer join dbo.PROC_TipoVersamento TV
on V.IDTipoVersamento = TV.IDTipoVersamento
inner join dbo.PROC_PraticaRiscossione PR
on V.IDPraticaRiscossioneAssociata = PR.IDPratica
inner join dbo.DA_Avviso A
on PR.IDDatiAvviso = A.IDAvviso
where DataAllibramento between '2012-09-08' and '2012-09-17' and A.IDFornitura = 4
group by V.IDTipoVersamento,month(DataAllibramento),TV.Descrizione
) as Q
order by Q.IDTipoVersamento, Q.Mese
Use COALESCE. It returns the first non-null value. E.g.
SELECT COALESCE(TV.Desc, 0)...
Will return 0 if TV.DESC is NULL.
You can try:
with dat as (select TV.[Desc] as TipyDesc, sum(Import) as ToImp, count(*) as N, month(Date) as Mounth
from /*DATA SOURCE HERE*/ as TV
group by [Desc], month(Date))
select [TipyDesc], ToImp, N, Mounth from dat
union all
select '0', 0, 0, 0 where (select count (*) from dat)=0
That should do what you want...
If it's ok to include the "0 0 0 0" row in a result set that has data, you can use a union:
SELECT TV.Desc as TipyDesc,
sum(Import) as TotImp,
count(*) as N,
month(Date) as Mounth
...
UNION
SELECT
0,0,0,0
Depending on the database, you may need a FROM for the second SELECT. In Oracle, this would be "FROM DUAL". For MySQL, no FROM is necessary
I have a table variable that holds orderID, UnitID and OrderServiceId (it is already populated via a query with insert statement).
I then have a query under this that returns 15 columns which also include the OrderId, UnitId, OrderServiceId
I need to only return the rows from this query where the same combination of OrderId, UnitId, and OrderServiceId are not in the table variable.
You can use NOT EXISTS. e.g.
FROM YourQuery q
WHERE NOT EXISTS
(
SELECT * FROM #TableVar t
WHERE t.OrderId = q.OrderId
and t.UnitId = q.UnitId
and t.OrderServiceId=q.OrderServiceId
)
select q.*
from (
MyQuery
) q
left outer join MyTableVariable t on q.ORDERID = t.ORDERID
and q.UNITID= t.UNITID
and q.ORDERSERVICESID = t.ORDERSERVICESID
where t.ORDERID is null
You can use EXCEPT | INTERSECT operators for this (link).
Example:
(select 3,4,1
union all
select 2,4,1)
intersect
(select 1,2,9
union all
select 3,4,1)