I have two sqlserver 2005 tables: Task table and Travel table.
I am trying to write a query that selects all records from the Task table for a specific Empid, and if the Task is travel, also get the mileage value from another table.
I expect only one row to be selected, but all rows in the Task table are returned.
The query I am using is
Select Tasklog.TaskLogPkey, Tasklog.Empid , Tasklog.Task, TravelLog.Mileage from
Tasklog
left join TravelLog
on
TaskLog.EmpId = 12 and TaskLog.Task ='Travel' and
TaskLog.TaskLogPkey = TravelLog.TaskLogPkey
But it makes no difference if I don’t include
-- TaskLog.EmpId = 12 and TaskLog.Task ='Travel' and
What am I doing wrong?
Clearly the following doesn't work:
Select Tasklog.TaskLogPkey, Tasklog.Empid , Tasklog.Task, TravelLog.Mileage from
Tasklog where TaskLog.EmpId = 12 and TaskLog.Task ='Travel'
left join TravelLog
on
TaskLog.TaskLogPkey = TravelLog.TaskLogPkey
These are the tables I am using:
Create table TaskLog(
TaskLogPkey int not null,
Empid int,
Task varchar(30)
)
Insert Tasklog values(1,12,'Sales')
Insert Tasklog values(2,4,'Travel')
Insert Tasklog values(3,63,'Meeting')
Insert Tasklog values(4,12,'Travel')
Insert Tasklog values(5,12,'Email')
Insert Tasklog values(6,4,'Travel')
Insert Tasklog values(7,63,'Meeting')
Insert Tasklog values(8,12,'PhoneCall')
Create table TravelLog(
TaskLogPkey int not null,
Mileage int
)
Insert TravelLog values(2,45)
Insert TravelLog values(4,25)
Insert TravelLog values(6,18)
When you perform an Outer join ( a left join is a Left Outer Join), you get all the records in the inner side of that join, --- no matter what predicates (filters) you specify on the other outer side in the join conditions.
To filter the other side you need to add a Where clause.
Select t.TaskLogPkey, t.Empid , t.Task, v.Mileage
From Tasklog t
Left Join TravelLog v
On t.TaskLogPkey = v.TaskLogPkey
Where t.Task ='Travel'
And t.EmpId = 12
TaskLog.EmpId = 12 and TaskLog.Task ='Travel' is part of the selection criteria, NOT join criteria.
And "Charles Bretana" beats me by less than 1 minute.
You should try placing a WHERE clause with the additional criteria:
Select Tasklog.TaskLogPkey, Tasklog.Empid , Tasklog.Task, TravelLog.Mileage
from Tasklog
left join TravelLog
on TaskLog.TaskLogPkey = TravelLog.TaskLogPkey
where TaskLog.EmpId = 12
and TaskLog.Task ='Travel'
See SQL Fiddle with Demo
Related
I'm making a query with having multiple non aggregated columns with group by clause but Postgres is throwing an error that I have to add non aggregated columns in group by or use any aggregate function on that column this is the query that I'm trying to run.
select
tb1.pipeline as pipeline_id,
tb3.pipeline_name as pipeline_name,
tb2."name" as integration_name,
cast(tb1.integration_id as VARCHAR) as integration_id,
tb1.created_at as created_at,
cast(tb1.id as VARCHAR) as batch_id,
sum(tb1.row_select) as row_select,
sum(tb1.row_insert) as row_insert,
from
table1 tb1
join
table2 tb2 on tb1.integration_id = tb2.id
join
table3 tb3 on tb1.pipeline = tb3.id
where
tb1.pipeline is not null
and tb1.is_super_parent = false
group by
tb1.pipeline
and I found one solution/hack for this error that is I added max function in all other non aggregated columns this solves my problem.
select
tb1.pipeline as pipeline_id,
max(tb3.pipeline_name) as pipeline_name,
max(tb2."name") as integration_name,
max(cast(tb1.integration_id as VARCHAR)) as integration_id,
max(tb1.created_at) as created_at,
max(cast(tb1.id as VARCHAR)) as batch_id,
sum(tb1.row_select) as row_select,
sum(tb1.row_insert) as row_insert,
from
table1 tb1
join
table2 tb2 on tb1.integration_id = tb2.id
join
table3 tb3 on tb1.pipeline = tb3.id
where
tb1.pipeline is not null
and tb1.is_super_parent = false
group by
tb1.pipeline
But I don't want to add max functions when there is no need for that second thing is that applying max to all other column query will be expensive so any other better approach that I can do to solve the above issue, thanks in advance.
Well the first thing you need is to learn to format your queries in so as to get an idea of their flow at a glance. Note due to the extra comma in row_insert, from your query will give a syntax error. With that said; How do you solve your issue?
You cannot avoid the additional aggregates or the expanded group by as long as the exist in the scope same query. You need to separate the aggregation from selection of additional columns. You basically have 2 choices:
Perform the aggregation in a CTE.
with sums (pipeline_id, row_select, row_insert) as
( select tb1.pipeline
, sum(tb1.row_select) as row_select
, sum(tb1.row_insert) as row_insert
table1 tb1
where tb1.pipeline is not null
and tb1.is_super_parent = false
group by tb1.pipeline
)
select s.pipeline_id
, tbl3.pipeline_name
, tb2."name" integration_name
, s.row_select
, s.row_insert
from sums s
join table2 tbl2 on (s.pipeline_id = tb2.id)
join table3 tbl3 on (s.pipeline_id = tb3.id);
Perform the aggregation in a sub-query.
select s.pipeline_id
, tbl3.pipeline_name
, tb2."name" integration_name
, s.row_select
, s.row_insert
from ( select tb1.pipeline
, sum(tb1.row_select) as row_select
, sum(tb1.row_insert) as row_insert
table1 tb1
where tb1.pipeline is not null
and tb1.is_super_parent = false
group by tb1.pipeline
) s
join table2 tbl2 on (s.pipeline_id = tb2.id)
join table3 tbl3 on (s.pipeline_id = tb3.id);
NOTE: Not tested as no sample data supplied.
I have 3 tables, Transaction, Transaction_Items and Transaction_History.
Where the Transaction is the parent table, while Transaction_Items and Transaction_History are the children tables, with one to many relationship.
When i try to join those tables together, if i have 2+ Transaction_History records, or 2+ Transaction_Items i get duplicated or triplicated record results.
This is the SQL query im currently using which works, but what worries me that in the future if i have to Join another one-to-many table, it will duplicate the results again.
I found a workaround for this, but i was just wondering if there is a better and cleaner way to do this ?
The results should be a PostgreSQL JSON array which will contain the Transaction_Items and Transaction_History
SELECT
TR.id AS transaction_id,
TR.transaction_number,
TR.status,
TR.status AS status,
to_json(TR_INV.list),
COUNT(TR_INV) item_cnt,
COUNT(THR) tr_cnt,
json_agg(THR)
FROM transaction_transaction AS TR
LEFT JOIN (
SELECT
array_agg(t) list, -- this is a workaround method
t.transaction_id
FROM (
SELECT
TR_INV.transaction_id transaction_id,
IT.id,
IT.stock_number,
CAT.key category_key,
ITP.description description,
ITP.serial_number serial_number,
ITP.color color,
ITP.manufacturer manufacturer,
ITP.inventory_model inventory_model,
ITP.average_cost average_cost,
ITP.location_in_store location_in_store,
ITP.firearm_caliber firearm_caliber,
ITP.federal_firearm_number federal_firearm_number,
ITP.sold_price sold_price
FROM transaction_transaction_item TR_INV
LEFT JOIN inventory_item IT ON IT.id = TR_INV.item_id
LEFT JOIN inventory_itemprofile ITP ON ITP.id = IT.current_profile_id
LEFT JOIN inventory_category CAT ON CAT.id = ITP.category_id
LEFT JOIN inventory_categorytype CAT_T ON CAT_T.id = CAT.category_type_id
) t
GROUP BY t.transaction_id
) TR_INV ON TR_INV.transaction_id = TR.id
LEFT JOIN transaction_transactionhistory THR ON THR.transaction_id = TR.id
AND (THR.audit_code_id = 44 OR THR.audit_code_id = 27 OR THR.audit_code_id = 28)
WHERE TR.store_id = 21
AND TR.transaction_type = 'Pawn_Loan' AND TR.date_made >= '2018-10-08'
GROUP BY TR.id, TR_INV.list
What you want to do can be achieved by not using joins, as shown below.
Because your actual tables have so many columns that I don't know and should not care. I just created the simplest forms of them for demonstration.
CREATE TABLE transactions (
tid serial PRIMARY KEY,
name varchar(40) NOT NULL
);
CREATE TABLE transaction_histories (
hid serial PRIMARY KEY ,
tid integer REFERENCES transactions(tid),
history varchar(40) NOT NULL
);
CREATE TABLE transaction_items (
iid serial PRIMARY KEY ,
tid integer REFERENCES transactions(tid),
item varchar(40) NOT NULL
);
INSERT INTO transactions(tid,name) Values(1, 'transaction');
INSERT INTO transaction_histories(tid, history) Values(1, 'history1');
INSERT INTO transaction_histories(tid, history) Values(1, 'history2');
INSERT INTO transaction_items(tid, item) Values(1, 'item1');
INSERT INTO transaction_items(tid, item) Values(1, 'item2');
select
t.*,
(select count(*) from transaction_histories h where h.tid= t.tid) h_count ,
(select json_agg(h) from transaction_histories h where h.tid= t.tid) h ,
(select count(*) from transaction_items i where i.tid= t.tid) i_count ,
(select json_agg(i) from transaction_items i where i.tid= t.tid) i
from transactions t;
I have two table with one of them is vertical i.e store only key value pair with ref id from table 1. i want to join both table and dispaly key value pair as a column in select. and also perform sorting on few keys.
T1 having (id,empid,dpt)
T2 having (empid,key,value)
select
T1.*,
t21.value,
t22.value,
t23.value,
t24.value
from Table1 t1
join Table2 t21 on t1.empid = t21.empid
join Table2 t22 on t1.empid = t22.empid
join Table2 t23 on t1.empid = t23.empid
where
t21.key = 'FNAME'
and t22.key = 'LNAME'
and t23.key='AGE'
The query you demonstrate is very inefficient (another join for each additional column) and also has a potential problem: if there isn't a row in T2 for every key in the WHERE clause, the whole row is excluded.
The second problem can be avoided with LEFT [OUTER] JOIN instead of [INNER] JOIN. But don't bother, the solution to the first problem is a completely different query. "Pivot" T2 using crosstab() from the additional module tablefunc:
SELECT * FROM crosstab(
'SELECT empid, key, value FROM t2 ORDER BY 1'
, $$VALUES ('FNAME'), ('LNAME'), ('AGE')$$ -- more?
) AS ct (empid int -- use *actual* data types
, fname text
, lname text
, age text);
-- more?
Then just join to T1:
select *
from t1
JOIN (<insert query from above>) AS t2 USING (empid);
This time you may want to use [INNER] JOIN.
The USING clause conveniently removes the second instance of the empid column.
Detailed instructions:
PostgreSQL Crosstab Query
I have a nested select query that is returning the proper amount of rows. The query builds a recordset and compares it to a table and returns the records in the query that are not in the table.
I converted the select query to an update query. I am trying to populate the table with the rows returned from the query. When I run the update query it is returning with zero rows to update. I dont understand why because the select query is returning record and I am using the same code in the update query.
Thanks
Select Query: (This is returning several records)
Select *
From
(SELECT DISTINCT
ProductClass,SalProductClass.[Description],B.Branch,B.BranchDesc,B.Salesperson,B.Name,
CAST(0 AS FLOAT) AS Rate,'N' AS Split
FROM (SELECT SalBranch.Branch,SalBranch.[Description] AS BranchDesc,A.Salesperson,A.Name
FROM (SELECT DISTINCT
Salesperson,Name
FROM SalSalesperson
) A
CROSS JOIN SalBranch
) B
CROSS JOIN SalProductClass
) C
Left Outer Join RateComm On
RateComm.ProductClass = C.ProductClass and
RateComm.Branch = C.Branch And RateComm.Salesperson = C.Salesperson
Where RateComm.ProductClass is Null
Update Query: (This is returning zero records)
UPDATE RateComm
SET RateComm.ProductClass=C.ProductClass,RateComm.ProdClassDesc=C.ProdClassDesc,
RateComm.Branch=C.Branch,RateComm.BranchDesc=C.BranchDesc,RateComm.Salesperson=C.Salesperson,
RateComm.Name=C.Name,RateComm.Rate=C.Rate,RateComm.Split=C.Split
FROM (SELECT DISTINCT
ProductClass,SalProductClass.[Description] AS ProdClassDesc,B.Branch,B.BranchDesc,B.Salesperson,B.Name,
CAST(0 AS FLOAT) AS Rate,'N' AS Split
FROM (SELECT SalBranch.Branch,SalBranch.[Description] AS BranchDesc,A.Salesperson,A.Name
FROM (SELECT DISTINCT
Salesperson,Name
FROM SalSalesperson
) A
CROSS JOIN SalBranch
) B
CROSS JOIN SalProductClass
) C
LEFT OUTER JOIN RateComm ON C.ProductClass=RateComm.ProductClass AND
C.Salesperson=RateComm.Salesperson AND C.Branch=RateComm.Branch
WHERE RateComm.ProductClass IS NULL
It's difficult to update what doesn't exist. Have you tried an INSERT query instead?
I have 50964218 records in a table. I am going to fetch the data from this table and insert into the same table. Which takes more time to manipulate. How optimize this query.
The Query is
INSERT INTO contacts_lists (contact_id, list_id, is_excluded, added_by_search)
SELECT contact_id, 68114 , TRUE, added_by_search
FROM contacts_lists cl1
WHERE list_id = 67579
AND is_excluded = TRUE
AND NOT EXISTS
(SELECT 1 FROM contacts_lists cl2
WHERE cl1.contact_id = cl2.contact_id AND cl2.list_id = 68114 )
index: list_id,contact_id
you will probably get better results with a left join:
select t1.[field], ...
from t1
left join t2
on [conditions]
where t2.[any pkey field] is null;