I'm trying to choose between what I think are two choices to get the same data.
I have one table that has the IDs of interest, and a set of 4 tables similar to each other that have data for those IDs. Once I have the rows for each ID, I'll use them to get maximum status field, or the minimum date field, etc. (across the 4 tables).
I can see structuring this query as 1 join to a union of the 4 tables, or as a union of 4 joins. Which is more efficient? FWIW, I find the first easier to understand, and probably easier to maintain.
Spelling out the two choices:
Join idTable against a sub-select of the 4 tables UNIONed together:
select ss.id, ss.study, ss.status, ss.date
from ( -- subselect ss
select tx.id, tx.study, tx.status, tx.date
from table_tx tx
UNION
select cfu.id, cfu.study, cfu.status, cfu.date
from table_cfu cfu
UNION
select sfu.id, sfu.study, sfu.status, sfu.date
from table_sfu sfu
UNION
select bsl.id, bsl.study, bsl.status, bsl.date
from table_bsl bsl
) ss
inner join
idTable id on id.id = ss.id AND id.study = ss.study
A union of idTable joined against each of the four:
select tx.id, tx.study, tx.status, tx.date
from table_tx tx
inner join
idTable id on id.id = tx.id AND id.study = tx.study
UNION
select cfu.id, cfu.study, cfu.status, cfu.date
from table_cfu cfu
inner join
idTable id on id.id = cfu.id AND id.study = cfu.study
UNION
select sfu.id, sfu.study, sfu.status, sfu.date
from table_sfu sfu
inner join
idTable id on id.id = sfu.id AND id.study = sfu.study
UNION
select bsl.id, bsl.study, bsl.status, bsl.date
from table_bsl bsl
inner join
idTable id on id.id = bsl.id AND id.study = bsl.study
Or is there a better choice other than these?
It's going to depend on what your data looks like in terms of the number of rows in each of the tables, so your best bet is going to be trying out both approaches and seeing if either is better.
If I assume, though, that each of your tables tx, cfu, sfu, and bsl contain a million rows, then I expect it would be faster to limit those 4 large sets to a single row before unioning them as opposed to creating a 4-million row set and then joining it.
SQL Server can transform the first to the second but not the reverse.
That said, there is no way to know which is better because it depends on a lot of things (row counts, filter selectivity, ...). The only sound answer is to look at the plan and/or test.
Related
I have two queries that I would like to combine. One query is left joining columns in the same table, the other query is left joining columns from two different tables. Both queries have the same table, just unsure how to properly set up the query.
1st Query:
SELECT BIZ_GROUP,
ORDER_ID,
STATION,
A.TC_DATE,
WANT_DATE,
TIME_SLOT,
JOB_CODE,
[ADDRESS],
CITY,
A.TECH_ID,
A.PREMISE,
ISNULL(B.LAST_ARRIVED, A.LAST_ARRIVE) AS ARRIVED,
ORDER_CLOSED,
COMP_STATUS,
WORK_STATUS,
REMARKS,
CORRECTION
FROM MET_timecommit A
LEFT JOIN(SELECT premise,
TC_DATE,
TECH_ID,
MIN(last_arrive) AS LAST_ARRIVED
FROM MET_timecommit
WHERE PREMISE IS NOT NULL
GROUP BY premise,
TC_DATE,
TECH_ID) B ON B.TC_DATE = A.TC_DATE
AND B.PREMISE = A.PREMISE
2nd query:
SELECT *
FROM MET_timecommit
LEFT JOIN (SELECT ORDER_ID,
created,
host_creation,
went_to
FROM workload
WHERE went_to >= getdate()-365) C ON C.went_to=MET_timecommit.TC_DATE
AND C.order_id=MET_timecommit.order_id
Evidently I am not used to this forum. You all don't have to be so rude. TDP was able to help me out based on what I provided. All other comments were unnecessary.
This should bring back the rows for both tables B and C for each row of table A:
SELECT A.BIZ_GROUP,
A.ORDER_ID,
A.STATION,
A.TC_DATE,
A.WANT_DATE,
A.TIME_SLOT,
A.JOB_CODE,
A.[ADDRESS],
A.CITY,
A.TECH_ID,
A.PREMISE,
ISNULL(B.LAST_ARRIVED, A.LAST_ARRIVE) AS ARRIVED,
A.ORDER_CLOSED,
A.COMP_STATUS,
A.WORK_STATUS,
A.REMARKS,
A.CORRECTION,
C.*
FROM MET_timecommit A
LEFT JOIN(SELECT premise,
TC_DATE,
TECH_ID,
MIN(last_arrive) AS LAST_ARRIVED
FROM MET_timecommit
WHERE PREMISE IS NOT NULL
GROUP BY premise,
TC_DATE,
TECH_ID) B ON B.TC_DATE = A.TC_DATE
AND B.PREMISE = A.PREMISE
LEFT JOIN (SELECT ORDER_ID,
created,
host_creation,
went_to
FROM workload
WHERE went_to >= getdate()-365) C ON C.went_to=A.MET_timecommit.TC_DATE
AND C.order_id=A.MET_timecommit.order_id
I have two tables one is the lookup table and the other is the data table. The lookup table has columns named cycleid, cycle. The data table has SID, cycleid, cycle. Below is the structure of the tables.
If you check the data table, the SID may have all the cycles and may not have all the cycles. I want to output the SID completed as well as missed cycles.
I right joined the lookup table and retrieved the missing as well as completed cycles. Below is the query I used.
SELECT TOP 1000 [SID]
,s4.[CYCLE]
,s4.[CYCLEID]
FROM [dbo].[data] s3 RIGHT JOIN
[dbo].[lookup_data] s4 ON s3.CYCLEID = s4.CYCLEID
The query is not displaying me the missed values when I query for all the SID's. When I specifically query for a SID with the below query i am getting the correct result including the missed ones.
SELECT TOP 1000 [SID]
,s4.[CYCLE]
,s4.[CYCLEID]
FROM [dbo].[data] s3 RIGHT JOIN [dbo].[lookup_data] s4
ON s3.CYCLEID = s4.CYCLEID
AND s3.SID = 101002
ORDER BY [SID], s4.[CYCLEID]
As I am supplying this query into tableau I cannot provide the sid value in the query. I want to return all the sid's and from tableau I will be do the rest of the things.
The expected output that i need is as shown below.
I wrote a cross join query like below to acheive my expected output
SELECT DISTINCT
tab.CYCLEID
,tab.SID
,d.CYCLE
FROM ( SELECT d.SID
,d.[CYCLE]
,e.CYCLEID
FROM ( SELECT e.sid
,e.CYCLE
FROM [db_temp].[dbo].[Sheet3$] e
) d
CROSS JOIN [db_temp].[dbo].[Sheet4$] e
) tab
LEFT OUTER JOIN [db_temp].[dbo].[Sheet3$] d
ON d.CYCLEID = tab.CYCLEID
AND d.SID = tab.SID
ORDER BY tab.SID
,tab.CYCLEID;
However I am not able to use this query for more scenarios as my data set have nearly 20 to 40 columns and i am having issues when i use the above one.
Is there any way to do this in a simpler manner with only left or right join itself? I want the query to return all the missing values and the completed values for the all the SID's instead of supplying a single sid in the query.
You can create a master table first (combine all SID and CYCLE ID), then right join with the data table
;with ctxMaster as (
select distinct d.SID, l.CYCLE, l.CYCLEID
from lookup_data l
cross join data d
)
select d.SID, m.CYCLE, m.CYCLEID
from ctxMaster m
left join data d on m.SID = d.SID and m.CYCLEID = d.CYCLEID
order by m.SID, m.CYCLEID
Fiddle
Or if you don't want to use common table expression, subquery version:
select d.SID, m.CYCLE, m.CYCLEID
from (select distinct d.SID, l.CYCLE, l.CYCLEID
from lookup_data l
cross join data d) m
left join data d on m.SID = d.SID and m.CYCLEID = d.CYCLEID
order by m.SID, m.CYCLEID
I am retrieving data from table ProductionReportMetrics where I have column NetRate_QuoteID. Then to that result set I need to get Description column.
And in order to get a Description column, I need to join 3 tables:
NetRate_Quote_Insur_Quote
NetRate_Quote_Insur_Quote_Locat
NetRate_Quote_Insur_Quote_Locat_Liabi
But after that my premium is completely off.
What am I doing wrong here?
SELECT QLL.Description,
QLL.ClassCode,
prm.NetRate_QuoteID,
QL.LocationID,
ISNULL(SUM(premium),0) AS NetWrittenPremium,
MONTH(prm.EffectiveDate) AS EffMonth
FROM ProductionReportMetrics prm
LEFT JOIN NetRate_Quote_Insur_Quote Q
ON prm.NetRate_QuoteID = Q.QuoteID
INNER JOIN NetRate_Quote_Insur_Quote_Locat QL
ON Q.QuoteID = QL.QuoteID
INNER JOIN NetRate_Quote_Insur_Quote_Locat_Liabi QLL
ON QL.LocationID = QLL.LocationID
WHERE YEAR(prm.EffectiveDate) = 2016 AND
CompanyLine = 'Ironshore Insurance Company'
GROUP BY MONTH(prm.EffectiveDate),
QLL.Description,
QLL.ClassCode,
prm.NetRate_QuoteID,
QL.LocationID
I think the problem in this table:
What Am I missing in this Query?
select
ClassCode,
QLL.Description,
sum(Premium)
from ProductionReportMetrics prm
LEFT JOIN NetRate_Quote_Insur_Quote Q ON prm.NetRate_QuoteID = Q.QuoteID
LEFT JOIN NetRate_Quote_Insur_Quote_Locat QL ON Q.QuoteID = QL.QuoteID
LEFT JOIN
(SELECT * FROM NetRate_Quote_Insur_Quote_Locat_Liabi nqI
JOIN ( SELECT LocationID, MAX(ClassCode)
FROM NetRate_Quote_Insur_Quote_Locat_Liabi GROUP BY LocationID ) nqA
ON nqA.LocationID = nqI.LocationID ) QLL ON QLL.LocationID = QL.LocationID
where Year(prm.EffectiveDate) = 2016 AND CompanyLine = 'Ironshore Insurance Company'
GROUP BY Q.QuoteID,QL.QuoteID,QL.LocationID
Now it says
Msg 8156, Level 16, State 1, Line 14
The column 'LocationID' was specified multiple times for 'QLL'.
It looks like DVT basically hit on the answer. The only reason you would get different amounts(i.e. duplicated rows) as a result of a join is that one of the joined tables is not a 1:1 relationship with the primary table.
I would suggest you do a quick check against those tables, looking for table counts.
--this should be your baseline count
SELECT COUNT(*)
FROM ProductionReportMetrics
GROUP BY MONTH(prm.EffectiveDate),
prm.NetRate_QuoteID
--this will be a check against the first joined table.
SELECT COUNT(*)
FROM NetRate_Quote_Insur_Quote Q
WHERE QuoteID IN
(SELECT NetRate_QuoteID
FROM ProductionReportMetrics
GROUP BY MONTH(prm.EffectiveDate),
prm.NetRate_QuoteID)
Basically you will want to do a similar check against each of your joined tables. If any of the joined tables are part of the grouping statement, make sure they are also in the grouping of the count check statement. Also make sure to alter the WHERE clause of the check count statement to use the join clause columns you were using.
Once you find a table that returns the incorrect number of rows, you will have your answer as to what table is causing the problem. Then you will just have to decide how to limit that table down to distinct rows(some type of aggregation).
This advice is really just to show you how to QA this particular query. Break it up into the smallest possible parts. In this case, we know that it is a join that is causing the problem, so take it one join at a time until you find the offender.
I have two kinds of query with did the same job here
Query 1 :
SELECT MP.MemberName FROM MemberProfile MP
LEFT JOIN Order O ON MP.MemberID = O.MemberID
WHERE O.TotalAmount >= 100
UNION
SELECT MP.MemberName FROM MemberProfile MP
LEFT JOIN Order O ON MP.MemberID = O.MemberID
WHERE O.Quantity >= 10
Query 2 :
;WITH cte AS (
SELECT MP.MemberName, O.Quantity, O.TotalAmount FROM MemberProfile MP
LEFT JOIN Order O ON MP.MemberID = O.MemberID
)
SELECT MemberName FROM cte WHERE TotalAmount >= 100
UNION
SELECT MemberName FROM cte WHERE Quantity >= 10
In real environment will be more complicated query, these just a simple version for other to read
Question:
Is it better to use CTE instead of using JOIN every single time, base on performance and also redundancy?
Is there a better way to do this UNION or even UNION ALL query other than these way.
I don't think that there will any big difference between CTE and JOIN in your case. SQL Server optimization will convert it to something complete different and these two queries will produce probably the same result. You can try to add indexes on TotalAmount and Quantity if selectivity is high.
Dear friends, below are my two SQL queries:
select distinct
a_bm.DestProvider_ID,
a_bm.DestCircel_ID,
convert(datetime,dbo.fnToDate(a_bm.BM_BillFrom),103) as fromdate,
convert(datetime,dbo.fnToDate(a_bm.BM_BillTo),103) as todate,
t_rec.TapInRec as BillRecevable,
t_rec.TapInRec as Billreceied
from Auditdata_BillingMaster a_bm
inner join TapInRecordMaster t_rec
on a_bm.DestProvider_ID = t_rec.DestProviderMaster_ID
and a_bm.DestCircel_ID = t_rec.DestCircelMaster_ID
and convert(datetime,dbo.fnToDate(a_bm.BM_BillFrom),103)> =
convert(datetime,t_rec.Months)
and convert(datetime,dbo.fnToDate(a_bm.BM_BillTo),103)<=
convert(datetime,t_rec.BillTo)
where a_bm.DestProvider_ID=4
and a_bm.DestCircel_ID=22
and a_bm.typeoffile=1
and convert(datetime,dbo.fnToDate(a_bm.BM_BillFrom),103)>=
convert(datetime,'6/1/2009')
and convert(datetime,dbo.fnToDate(a_bm.BM_BillFrom),103)<=
convert(datetime,'7/30/2009')
select Temp_tbl.fromdate from Temp_tbl Temp_tbl
inner join (
select
convert(datetime,dbo.fnToDate(BM_BillFrom),103) as a1,
convert(datetime,dbo.fnToDate(BM_BillTo),103) as b1,
count(*) as c1,
am_bm.DestProvider_ID,
am_bm.DestCircel_ID
from Auditdata_BillingMaster am_bm
inner join Temp_tbl tmp
on tmp.Provider_ID=am_bm.DestProvider_ID
and tmp.Circel_ID=am_bm.DestCircel_ID
where convert(datetime,tmp.fromdate)>=
convert(datetime,dbo.fnToDate(am_bm.BM_BillFrom),103)
and convert(datetime,tmp.todate) <=
convert(datetime,dbo.fnToDate(am_bm.BM_BillTo),103)
group by
convert(datetime,dbo.fnToDate(BM_BillFrom),103),
convert(datetime,dbo.fnToDate(BM_BillTo),103),
am_bm.DestProvider_ID,
am_bm.DestCircel_ID
) b
on Temp_tbl.Provider_ID = b.DestProvider_ID
and Temp_tbl.Circel_ID = b.DestCircel_ID
and convert(datetime,Temp_tbl.fromdate,101)>= convert(datetime,(b.a1),101)
and convert(datetime,Temp_tbl.todate) <= convert(datetime,(b.b1),101)
I want to merge above 2 SQL query in SQL Server 2000.
Please help me.
Thanks in advance.
Do you mean to JOIN or UNION both tables?
If you mean to JOIN both query results, simply take both results as input for JOIN statement.
How you join both results is really dependent on your database design. Preferably the join is based on referential integrity enforcing the relationship between the results to ensure data integrity. But since you do not mention the join condition, let me assume you will join based on DestProvider_ID & DestCircel_ID.
select
result1.DestProvider_ID,
result1.DestCircel_ID,
result1.fromdate,
result1.todate,
result1.BillRecevable,
result1.Billreceied,
result2.fromdate
from
( *your first query* ) as result1
inner join
(select
Temp_tbl.fromdate,
am_bm.DestProvider_ID,
am_bm.DestCircel_ID
from Temp_tbl Temp_tbl
*the rest of your second query*
) as result2 on result1.DestProvider_ID = result2.DestProvider_ID
and result1.DestCircel_ID = result2.DestCircel_ID
UNION:
If you want to take multiple select statements and combine them into one result set, UNION statement is the easiest way to go:
SELECT column1a, column2a, column3a FROM tableA
UNION
SELECT column1b, column2b, column3b FROM tableB
This is possible only if:
both queries have same number of columns
Corresponding columns in each query expression must be of the same data type
data type of column1a == column1b
data type of column2a == column2b
data type of column3a == column3b
Since both of your queries do not have same number of columns, you can't merge them, at least with UNION select.