I'm migrating a client's software database from Oracle to PostgreSQL, and I have some trouble understanding a query, what it does, and consequently how to migrate it.
The query is:
SELECT *
FROM TBL1, TBL2, TBL3, TBL4
WHERE TBL3.Project_ID = TBL1.Project_ID
AND TBL2.Type_ID = TBL1.Type_ID
AND TBL4.PROPERTY_NAME(+)='Id'
AND TBL4.Entity_ID(+)=TBL1.Entity_ID
And the part I don't get, is the outer join (+) on 'Id'.
A join on a table, OK, but on a string? I've no idea of what it does.
Do someone has an idea?
Thanks.
TBL4.PROPERTY_NAME(+)='Id' means when the line was inner joined, then the value has to be 'Id', but when the line was outer joined, the condition is evaluated as true
however you should rewrite the statement to the standard as:
SELECT *
FROM TBL1
JOIN TBL2 ON TBL2.Type_ID = TBL1.Type_ID
JOIN TBL3 ON TBL3.Project_ID = TBL1.Project_ID
LEFT JOIN TBL4 ON TBL4.Entity_ID=TBL1.Entity_ID AND TBL4.PROPERTY_NAME='Id'
This is the equivalent of the following query using ANSI join syntax:
SELECT *
FROM TBL1 t1
INNER JOIN TBL2 t2 ON (t1.Type_ID = t2.Type_ID)
INNER JOIN TBL3 t3 ON (t3.Project_ID = t1.Project_ID)
LEFT JOIN TBL4 t4 ON (t4.Entity_ID = t1.Entity_ID AND t4.PROPERTY_NAME = 'Id')
You're not joining to a string, merely specifying a join condition that's based on one.
Related
I am trying to join three tables using a sub query.
The result of the first left outer join is to be used with another table to get a composite view with all attributes.
I am getting an error where the compile says, Unknown Command for the table in the second join clause.
When I create two independent views and then join then it works fine.
(select
l.ENROLLED_CONTENT,
l.LEARNING_ENROLLMENT_LEARNER,
l.EMPLOYEE_ID,
l.JOB_FAMILY_GROUP,
l.EMPLOYEE_TYPE,
l.JOB_FAMILY,
l.LEARNING_ENROLLMENT,
l.COMPLETION_STATUS,
l.COMPLETION_DATE,
l.EXPIRATION_DATE,
l.CF_LRV_LEARNING_CONTENT_NUMBER,
l.LEARNING_CONTENT_DETAIL,
l.LEARNING_CONTENT_TYPE,
l.LESSON_TYPE,
e.id# "WK_WORKER_ID"
from tgt_workday.learning l
left outer join ods_hrmaster.employee e
on l.EMPLOYEE_ID = e.employee#) t1
left outer join ( select
per_ids_id,
per_id,
id_pureid from
ods_pure.person_ids
) t2 on t1.wk_worker_id = t2.value where t2.type = 'Employee ID';
You can write it in a simple way. There is no need to make sub-queries as:
SELECT L.ENROLLED_CONTENT,
L.LEARNING_ENROLLMENT_LEARNER,
L.EMPLOYEE_ID,
L.JOB_FAMILY_GROUP,
L.EMPLOYEE_TYPE,
L.JOB_FAMILY,
L.LEARNING_ENROLLMENT,
L.COMPLETION_STATUS,
L.COMPLETION_DATE,
L.EXPIRATION_DATE,
L.CF_LRV_LEARNING_CONTENT_NUMBER,
L.LEARNING_CONTENT_DETAIL,
L.LEARNING_CONTENT_TYPE,
L.LESSON_TYPE,
E.ID# "WK_WORKER_ID"
FROM TGT_WORKDAY.LEARNING L
LEFT OUTER JOIN ODS_HRMASTER.EMPLOYEE E
ON L.EMPLOYEE_ID = E.EMPLOYEE#
LEFT OUTER JOIN ODS_PURE.PERSON_IDS T2
ON E.ID# = T2.VALUE
AND T2.TYPE = 'Employee ID';
Once you use the outer joined table's column in WHERE clause, It will result in the same result as inner join(there is another ways to use it in WHERE clause though). So it is better to avoid using outer joined table's column in the WHERE clause.
Try as
SELECT *
FROM ( (SELECT l.ENROLLED_CONTENT,
l.LEARNING_ENROLLMENT_LEARNER,
l.EMPLOYEE_ID,
l.JOB_FAMILY_GROUP,
l.EMPLOYEE_TYPE,
l.JOB_FAMILY,
l.LEARNING_ENROLLMENT,
l.COMPLETION_STATUS,
l.COMPLETION_DATE,
l.EXPIRATION_DATE,
l.CF_LRV_LEARNING_CONTENT_NUMBER,
l.LEARNING_CONTENT_DETAIL,
l.LEARNING_CONTENT_TYPE,
l.LESSON_TYPE,
e.id# "WK_WORKER_ID"
FROM tgt_workday.learning l
LEFT OUTER JOIN ods_hrmaster.employee e
ON l.EMPLOYEE_ID = e.employee) t1
LEFT OUTER JOIN
(SELECT per_ids_id, per_id, id_pureid FROM ods_pure.person_ids) t2
ON t1.wk_worker_id = t2.VAL AND t2.TYPE = 'Employee ID')
I have a below query
How to use full outer join for TABLE T4 for getting all records?
WHERE
(DB.T4.AUTH_REV_NO=DB.T2.AUTH_REV_NO
AND DB.T4.AUTH_NO=DB.T2.AUTH_NO)
AND (DB.T2.AUTH_CURR_IN='Y' )
AND (DB.T3.AUTH_NO=DB.T2.AUTH_NO)
AND (DB.T3.AUTH_REV_NO=DB.T2.AUTH_REV_NO )
AND (DB.T6.FNC_ID=DB.T4.FNC_ID)
AND (DB.T7.FNC_SEG_ID=DB.T6.FNC_SEG_ID)
AND (DB.T1.SCT_ID(+)=DB.T7.SCT_ID
AND DB.T1.FNC_SEG_ID(+)=DB.T7.FNC_SEG_ID)
AND (DB.T8.NDE_ID=DB.T12.NDE_ID)
AND (DB.T7.FNC_SEG_ID=DB.T8.FNC_SEG_ID)
AND (DB.T7.SCT_ID=DB.T8.SCT_ID)
AND ((DB.T12.NDE_ID=DB.T6.NDE_STRT_ID)
OR (DB.T12.NDE_ID=DB.T6.NDE_END_ID))
AND (DB.T5.FNC_ID(+)=DB.T4.FNC_ID)
AND (T13_A4.REF_ID(+)=DB.T5.REF_TONE_TYP_ID)
AND (fne.FNC_SEG_ID=DB.T8.FNC_SEG_ID)
AND (fne.NDE_ID=DB.T8.NDE_ID)
AND (fne.SCT_ID=DB.T8.SCT_ID)
AND fnode.NDE_ID=DB.T6.NDE_STRT_ID
AND tnode.NDE_ID=DB.T6.NDE_END_ID
AND (DB.T4.REF_FNC_TYP_ID=T13_A1.REF_ID)
AND (ne_port.NDE_EQP_ID=fne.NDE_EQP_ID)
AND (ne_port.NDE_EQP_PRN_ID=ne_card.NDE_EQP_ID)
AND (ne_card.NDE_EQP_PRN_ID=ne_shelf.NDE_EQP_ID)
AND (ne_shelf.NDE_EQP_PRN_ID=ne_rack.NDE_EQP_ID)
AND (eq.EQP_ID=ne_card.EQP_ID)
AND (eq.REF_EQP_CLS_ID=T13_A2.REF_ID)
AND (DB.T3.REF_AUTH_STS_ID=T13_A3.REF_ID)
AND (DB.T3.AUTH_STS_ID
IN (SELECT MAX(DB.T3.AUTH_STS_ID) FROMDB.T3
WHERE (DB.T3.AUTH_NO,DB.T3.AUTH_REV_NO)
IN
(SELECT
DB.T3.AUTH_NO,
MAX(DB.T3.AUTH_REV_NO)
FROM
DB.T3
GROUP BY
DB.T3.AUTH_NO)
GROUP BY
DB.T3.AUTH_NO))
How to use full outer join for TABLE T4 and for COLUMN FNC_TONE_LVL_QT to get all records.
Please help.
You posted a whole lot of "joins". I'm not going to rewrite it for you, but - I'd suggest you to switch to a more recent explicit JOIN syntax which makes things somewhat simpler and easier to understand as you'd separate joins from conditions. Moreover, it allows you to outer join the same table to more than just one another table, which is impossible with the old (+) Oracle's outer join operator.
Something like this
select ...
from table_1 a left join table_2 b on a.id = b.id
full outer join table_3 c on c.id = a.id
...
I want some help to optimize this SQL Query.
This is working completely fine. I just want to reduce the runtime of this query
select distinct
o.usrp_order_number,t.*
from ms_bvoip_order_extension oe
inner join ms_order o on oe.ms_order_id = o.ms_order_id
inner join ms_sub_order so on so.ms_order_id = o.ms_order_id
inner join ms_job j on j.entity_id = so.ms_sub_order_id
left join mstask t ON t.wf_job_id = j.wf_job_id
where
o.order_type = 900
and o.entered_date between date_sub(current_date(),53) and
date_sub(current_date(),3)
and j.entity_type = 5 and t.name RLIKE 'Error|Correct|Create AOTS Ticket' and t.wf_job_id is not null
order by
o.usrp_order_number
The WHERE conditions are being executed after joins in Hive (though CBO and PPD may change this behavior), better study the EXPLAIN output for both queries. You can move conditions like this: o.order_type = 900 to the join ON clause to reduce rows on join. Only non-equi conditions involving both tables columns are not allowed in the join ON clause in Hive. Also table t is left-joined, but conditions in the where: t.name RLIKE 'Error|Correct|Create AOTS Ticket' and t.wf_job_id is null and t.ORIGINAL_START_DATE is not null transform left join to the inner join. Check do you need INNER or LEFT JOIN
select distinct
o.usrp_order_number,t.*
from ms_bvoip_order_extension oe
inner join ms_order o
on oe.ms_order_id = o.ms_order_id
and o.order_type = 900
and and o.entered_date between date_sub(current_date(),53) and date_sub(current_date(),3)
inner join ms_sub_order so on so.ms_order_id = o.ms_order_id
inner join ms_job j on j.entity_id = so.ms_sub_order_id
and j.entity_type = 5
left join mstask t on t.wf_job_id = j.wf_job_id
and t.name RLIKE 'Error|Correct|Create AOTS Ticket'
and t.wf_job_id is null
and t.ORIGINAL_START_DATE is not null
order by o.usrp_order_number
Also read this answer about configuration settings: https://stackoverflow.com/a/48487306/2700344
be sure you have proper index on
table ms_order a composite index on columns entered_date, order_type, ms_order_id
table ms_job a composite index on columns entity_type, entity_id
table mstask a composite index on columns wf_job_id, ORIGINAL_START_DATE
table ms_sub_order an index on column ms_order_id
table ms_bvoip_order_extension and index on column ms_order_id
You will need to add indexes for the columns that you are filtering by.
We do not know how many records each of your tables are holding, but the t.name RLIKE criteria should be evaluated as the very last item. I would rewrite your query based on the following idea:
select ...
from
(
select ...
inner join ...
inner join ...
inner join ...
left join ...
where ...
) temporary
where temporary.somename RLIKE 'Error|Correct|Create AOTS Ticket'
o.usrp_order_number
If the query is not very dynamic, then you can even cache the results for a while.
So i have this:
SELECT p.plantnaam,o.levcode,o.offerteprijs
FROM plant p, offerte o
JOIN (SELECT plantcode , MIN(offerteprijs) AS offprijs
FROM offerte
GROUP BY plantcode) s
ON s.plantcode = p.plantcode
AND s.offprijs = o.offerteprijs
ORDER BY p.plantnaam,l.levcode
Appearently on the 6th row, p.plantcode is suddenly magically an invalid identifier. Why is this? and why are all the others from the exact same table perfectly fine before that point?
The problem is that you are mixing JOINs. You have both implicit and explicit joins. The explicit JOIN syntax with the ON clause has a higher precedence over the implicit join with the commas. As a result the alias for the plant and the offerte tables will not be available in the ON clause. Try using the same JOIN type throughout:
SELECT p.plantnaam, o.levcode, o.offerteprijs
FROM
(
SELECT plantcode , MIN(offerteprijs) AS offprijs
FROM offerte
GROUP BY plantcode
) s
INNER JOIN plant p
ON s.plantcode = p.plantcode
INNER JOIN offerte o
ON s.offprijs = o.offerteprijs
ORDER BY p.plantnaam, l.levcode
Im trying to convert a SQL join to LINQ. I need some help in getting the nested join working in LINQ.
This is my SQL query, Ive cut it short just to show the nested join in SQL:
select distinct
txtTaskStatus as TaskStatusDescription,
txtempfirstname+ ' ' + txtemplastname as RaisedByEmployeeName,
txtTaskPriorityDescription as TaskPriorityDescription,
dtmtaskcreated as itemDateTime,
dbo.tblTask.lngtaskid as TaskID,
dbo.tblTask.dtmtaskcreated as CreatedDateTime,
convert(varchar(512), dbo.tblTask.txttaskdescription) as ProblemStatement,
dbo.tblTask.lngtaskmessageid,
dbo.tblMessage.lngmessageid as MessageID,
case when isnull(dbo.tblMessage.txtmessagesubject,'') <> '' then txtmessagesubject else left(txtmessagedescription,50) end as MessageSubject,
dbo.tblMessage.txtmessagedescription as MessageDescription,
case when dbo.tblMessage.dtmmessagecreated is not null then dbo.tblMessage.dtmmessagecreated else CAST(FLOOR(CAST(dtmtaskcreated AS DECIMAL(12, 5))) AS DATETIME) end as MessageCreatedDateTime
FROM
dbo.tblAction RIGHT OUTER JOIN dbo.tblTask ON dbo.tblAction.lngactiontaskid = dbo.tblTask.lngtaskid
LEFT OUTER JOIN dbo.tblMessage ON dbo.tblTask.lngtaskmessageid = dbo.tblMessage.lngmessageid
LEFT OUTER JOIN dbo.tblTaskCommentRecipient
RIGHT OUTER JOIN dbo.tblTaskComment ON dbo.tblTaskCommentRecipient.lngTaskCommentID = dbo.tblTaskComment.lngTaskCommentID
ON dbo.tblTask.lngtaskid = dbo.tblTaskComment.lngTaskCommentTaskId
A more seasoned SQL programmer wouldn't join that way. They'd use strictly left joins for clarity (as there is a strictly left joining solution available).
I've unraveled these joins to produce a hierarchy:
Task
Action
Message
TaskComment
TaskCommentRecipient
With associations created in the linq to sql designer, you can reach these levels of the hierarchy:
//note: these aren't outer joins
from t in db.Tasks
let actions = t.Actions
let message = t.Messages
let comments = t.TaskComments
from c in comments
let recipients = c.TaskCommentRecipients
DefaultIfEmpty produces a default element when the collection is empty. Since these are database rows, a default element is a null row. That is the behavior of left join.
query =
(
from t in db.Tasks
from a in t.Actions.DefaultIfEmpty()
from m in t.Messages.DefaultIfEmpty()
from c in t.Comments.DefaultIfEmpty()
from r in c.Recipients.DefaultIfEmpty()
select new Result()
{
TaskStatus = ???
...
}
).Distinct();
Aside: calling Distinct after a bunch of joins is a crutch. #1 See if you can do without it. #2 If not, see if you can eliminate any bad data that causes you to have to call it. #3 If not, call Distinct in a smaller scope than the whole query.
Hope this helps.
SELECT [t0].[OrderID], [t0].[CustomerID], [t0].[EmployeeID], [t0].[OrderDate], [t0].[RequiredDate], [t0].[ShippedDate], [t0].[ShipVia], [t0].[Freight], [t0].[ShipName], [t0].[ShipAddress], [t0].[ShipCity], [t0].[ShipRegion], [t0].[ShipPostalCode], [t0].[ShipCountry]
FROM [Orders] AS [t0]
LEFT OUTER JOIN ([Order Details] AS [t1]
INNER JOIN [Products] AS [t2] ON [t1].[ProductID] = [t2].[ProductID]) ON [t0].[OrderID] = [t1].[OrderID]
can be write as
from o in Orders
join od in (
from od in OrderDetails join p in Products on od.ProductID equals p.ProductID select od)
on o.OrderID equals od.OrderID into ood from od in ood.DefaultIfEmpty()
select o