I have two tables,
[TABLE_1]
| ID1 | ID2 | ID3 |
|-----+-----+-----|
| 200 | 125 | 300 |
| 206 | 128 | 650 |
| 230 | 543 | 989 |
[TABLE_2]
| ID1 | ID2 | ID3 | Date |
|-----+-----+-----+--------|
| 200 | 125 | 300 | 1/1/18 |
| 200 | 125 | 300 | 1/1/19 |
| 206 | 128 | 650 | 1/1/13 |
| 206 | 128 | 650 | 1/2/13 |
| 206 | 128 | 650 | 9/5/05 |
I'm trying to Left Join TABLE_1 to TABLE_2 while filtering the output so only rows where Date is at its maximum for those classifications are displayed. I simplified the data in my tables a little bit, but there's NO overall max date that can be used for all items in the table, the max date is unique to each item.
Desired results on the above example would be:
| ID1 | ID2 | ID3 | Date |
|-----+-----+-----+--------|
| 200 | 125 | 300 | 1/1/19 |
| 206 | 128 | 650 | 1/2/13 |
Here's my latest attempt at the query. It seems a little too complicated as I'm relatively new with SQL and has been running without giving a result for a long time now so I'm afraid it may be in an endless loop somehow:
SELECT DISTINCT *
FROM TABLE_1 t1
LEFT JOIN TABLE_2 t2
ON t1.ID1 = t2.ID1
AND t1.ID2 = t2.ID2
AND t1.ID3 = t2.ID3
WHERE t2.Date = (SELECT MAX(Date) FROM Table_2
WHERE t1.ID1 = t2.ID2
AND t1.ID2 = t2.ID2
AND t1.ID3 = t2.ID3);
Any help on how better to query this will be greatly appreciated, thanks!
Notes: The column names are not identical (I know this would cause an error), I only labeled them like that for simplification.
For your given results, why not just aggregate table 2?
select id1, id2, id3, max(date)
from table2
group by id1, id2, id3;
If you need to filter this only for the triples in table1, then:
select t2.id1, t2.id2, t2.id3, max(t2.date)
from table2 t2 join
table1 t1
on t2.id1 = t1.id1 and t2.id2 = t1.id2 and t2.id3 = t1.id3
group by t2.id1, t2.id2, t2.id3;
So as per the comments, I think the following is the complete code:
SELECT
T1.ID1,
T1.ID2,
T1.ID3,
MAX(T2.DATE) AS DATE
FROM
TABLE1 T1
-- USED LEFT JOIN AS NOT SURE IF THERE IS ATLEAST ONE ROW IN T2 FOR EACH ROW IN T1
LEFT JOIN (
SELECT
ID1,
ID2,
ID3,
MAX(DATE)
FROM
TABLE2
GROUP BY
ID1,
ID2,
ID3
) T2 ON T2.ID1 = T1.ID1
AND T2.ID2 = T1.ID2
AND T2.ID3 = T1.ID3;
Cheers!!
You can also use the WITH statement, preaggregating the entries in table 2:
WITH agg_table_2 AS (
SELECT
ID1
,ID2
,ID3
,MAX(DATE) AS MAX_DATE
FROM TABLE_2
GROUP BY
ID1
,ID2
,ID3
)
SELECT
T1.ID1
,T1.ID2
,T1.ID3
,T2.MAX_DATE
FROM TABLE_1 T1
--LEFT
JOIN TABLE_2 T2
ON T1.ID1 = T2.ID1
AND T1.ID2 = T2.ID2
AND T1.ID3 = T2.ID3
;
Note that I actually commented out the LEFT in JOIN as in your desired output 230, 543, 989 was not present. Uncomment it, if you want to keep that entry with NULL value assigned.
Related
I have two tables Table1 and Table2. I wanted to join the two tables data based on the TIME_STAMP data field
I have tried the below query but I am not able to get the expected result
Table 1
CATEGORY_ID ID TIME_STAMP VALUE
-------------------------------------
1 444 30-Mar-17 XXX
1 444 31-Jul-18 YYY
1 444 15-Jan-19 ZZZ
Table 2
CATEGORY_ID ID TIME_STAMP VALUE
------------------------------------------
2 444 30-Mar-17 10/31/2017
2 444 30-May-18 10/25/2018
2 444 13-Jun-19 10/25/2018
Actual Result:
TIME_STAMP Table 1 VALUE Table 2 value
-------------------------------------------
30-Mar-17 XXX 10/31/2017
31-Jul-18 YYY NULL
15-Jan-19 ZZZ NULL
Query :
SELECT
T1.TIME_STAMP ,
T1.X_VALUE,
T2.X_VALUE
FROM
TABLE1 T1
LEFT OUTER JOIN TABLE2 T2 ON T1.ID = T2.ID
AND
TO_CHAR(T1.TIME_STAMP,'MM/DD/YYYY')
=TO_CHAR(T2.TIME_STAMP,'MM/DD/YYYY')
AND
T2.CATEGORY_ID=2
WHERE
T1.CATEGORY_ID =1 AND T1.ID= 444
Expected Result:
TIME_STAMP Table1 VALUE Table2 VALUE
-----------------------------------------
30-Mar-17 XXX 10/31/2017
30-May-18 NULL 10/25/2018
31-Jul-18 YYY NULL
15-Jan-19 ZZZ NULL
13-Jun-19 NULL 10/25/2018
FULL OUTER JOIN with filtering is tricky. I recommend using a subquery for the filtering criteria:
select coalesce(t1.time_stamp, t2.time_stamp) as time_stamp,
t1.x_value, t2.x_value
from (select t1.*
from table1 t1
where t1.CATEGORY_ID = 1 and T1.ID = 444
) t1 full join
(select t2.*
from table2 t2
where t2.id = 444 and t2.category_id = 2
) t2
on t2.id = t1.id and
trunc(t2.time_stamp) = trunc(t1.time_stamp);
Based on your expected result I think you want to do a FULL OUTER JOIN on the TIME_STAMP column.
You could do something like this.
SELECT COALESCE(t1.time_stamp, t2.time_stamp) AS TIME_STAMP,
t1.value as T1_value,
t2.value as T2_value
FROM table01 t1
FULL OUTER JOIN table02 t2 ON t1.time_stamp = t2.time_stamp
+-------------+-----------+------------+
| TIME_STAMP | T1_value | T2_value |
+-------------+-----------+------------+
| 2017-03-30 | XXX | 10/31/2017 |
| 2018-07-31 | YYY | (null) |
| 2019-01-15 | ZZZ | (null) |
| 2018-05-30 | (null) | 10/25/2018 |
| 2019-06-13 | (null) | 10/25/2018 |
+-------------+-----------+------------+
Note: I have used SQL Server since you haven't mentioned a DBMS.
before you join the two tables with timestamp, you need trunc the timestamp to Date.
like TRUNC("TimeStamp", DATE)
SELECT COALESCE(t1.time_stamp, t2.time_stamp) AS TIME_STAMP,
t1.value as T1_value,
t2.value as T2_value
FROM table01 t1
FULL OUTER JOIN table02 t2
ON trunc(t1.time_stamp, 'DATE') = trunc(t2.time_stamp, 'DATE');
I am trying to join two tables one is a unique feature the seconds is readings taken on several dates that relate to the unique features. I want all of the records in the first table plus the most recent reading. I was able to get the results I was looking for before adding the shape field. By using the code
SELECT
Table1.Name, Table1.ID, Table1.Shape,
Max(Table2.DATE) as Date
FROM
Table1
LEFT OUTER JOIN
Table2 ON Table1.ID = table2.ID
GROUP BY
Table1.Name, Table1.ID, Table1.Shape
The shape field is a geometry type and I get the error
'The type "Geometry" is not comparable. It can not be use in the Group By Clause'
So I need to go about it a different way, but not sure how.
Below is a sample of the two tables and the desired results.
Table1
Name| ID |Shape
AA1 | 1 | X
BA2 | 2 | Y
CA1 | 3 | Z
CA2 | 4 | Q
Table2
ID | Date
1 | 5/27/2013
1 | 6/27/2014
2 | 5/27/2013
2 | 6/27/2014
3 | 5/27/2013
3 | 6/27/2014
My Desired Result is
Name| ID |Shape |Date
AA1 | 1 | X | 6/27/2014
BA2 | 2 | Y | 6/27/2014
CA1 | 3 | Z | 6/27/2014
CA2 | 4 | Q | Null
You can do the aggregation on Table2 in a CTE, finding the MAX(DATE) for each ID, and then join that result to Table1:
WITH AggregatedTable2(ID, MaxDate) AS
(
SELECT
ID, MAX(DATE)
FROM
Table2
GROUP BY
ID
)
SELECT
t1.ID, t1.Name, t1.Shape, t2.MaxDate
FROM
Table1 t1
LEFT JOIN
AggregatedTable2 t2 ON t1.ID = t2.ID
Try casting geometry as a varchar.
Select Table1.Name, Table1.ID, cast(Table1.Shape as varchar(1)) AS Shape, Max(Table2.DATE) as Date
FROM Table1 LEFT OUTER JOIN
Table2 ON Table1.ID = table2.ID
Group By Table1.Name, Table1.ID, cast(Table1.Shape as varchar(1))
Try this:
SELECT t1.Name
, t1.ID
, t1.Shape
, MAX(t2.Date) As Date
FROM Table1 AS t1
LEFT JOIN Table2 AS t2
ON t2.ID = t1.ID
GROUP
BY t1.Name
, t1.ID
, t1.Shape
I have two tables in oracle database
Table 1 say table1 with fields (id, name)
Records e.g.
###############
id | name
1 | Chair
2 | Table
3 | Bed
###############
and Table 2 say table2 with fields (id, table1_id, date, price)
##############################
id |table1_id| date | price
1 | 1 | 2013-09-09 | 500
2 | 1 | 2013-08-09 | 300
3 | 2 | 2013-09-09 | 5100
4 | 2 | 2013-08-09 | 5000
5 | 3 | 2013-09-09 | 10500
################################
What I want to achieve is to retrieve all the latest price of items from table 2
Result of SQL should be like
##############################
id |table1_id| date | price
1 | 1 | 2013-09-09 | 500
3 | 2 | 2013-09-09 | 5100
5 | 3 | 2013-09-09 | 10500
################################
I am able to run in mysql by following query
SELECT t2.id, t1.id, t1.name, t2.date, t2.price
FROM table1 t1 JOIN table2 t2
ON (t1.id = t2.table1_id
AND t2.id = (
SELECT id
FROM table2
WHERE table1_id = t1.id
ORDER BY table2.date DESC
LIMIT 1
));
but it's not working in ORACLE, Here i Need a query which can run on both server with minor modification
You may try this (shoud work in both MySQL and Oracle):
select t2.id, t2.table1_id, t2.dat, t2.price
from table1 t1 join table2 t2 on (t1.id = t2.table1_id)
join (select table1_id, max(dat) max_date
from table2 group by table1_id) tmax
on (tmax.table1_id = t2.table1_id and tmax.max_date = t2.dat);
This query may return several rows for the same table1_id and date if there are several prices in table2, like this:
##############################
id |table1_id| date | price
1 | 1 | 2013-09-09 | 500
2 | 1 | 2013-09-09 | 300
It's possible to change the query to retrieve only 1 row for each table1_id, but there should be some additional requirements (which row to choose in the above example)
if it doesn't matter then you may try this:
select max(t2.id) as id, t2.table1_id, t2.dat, max(t2.price) as price
from table1 t1 join table2 t2 on (t1.id = t2.table1_id)
join (select table1_id, max(dat) max_date
from table2 group by table1_id) tmax
on (tmax.table1_id = t2.table1_id and tmax.max_date = t2.dat)
group by t2.table1_id, t2.dat;
You can try this using GROUP BY instead, since you're not retrieving the product name from table1 except the product id (which is already in table2)
SELECT id,table1_id,max(date),price
FROM table2
GROUP BY id,table1_id,price
this is what you want :
select t2.id,t2.table1_id,t1.name,t2.pricedate,t2.price
from table1 t1
join
(
select id,table1_id, pricedate,price, row_number() over (partition by table1_id order by pricedate desc) rn
from table2
) t2
on t1.id = t2.table1_id
where t2.rn = 1
I improved my question with example tables for a better understanding
I have 3 tables with following rows:
TABLE1 t1 TABLE t2 TABLE t3
ID NAME OBS ID HW_VER ID SERIAL
----------------- ----------- ------------
1 | Name1 | Obs1 1 | HWVer1 5 | Serial5
2 | Name2 | Obs2 2 | HWVer2 6 | Serial6
3 | Name3 | Obs3 3 | HWVer3 7 | Serial7
4 | Name4 | Obs4
5 | Name5 | Obs5
6 | Name6 | Obs6
7 | Name7 | Obs7
Now, I want to select the id, name and obs when 2 conditions are fulfilled:
the id is present in t2 or t3 (never in both);
it refers to either t2 or t3 attributes (eg. t2.HW_VER='HWVER1'), never on both
I did something like this, but it's wrong:
SELECT DISTINCT t1.id, t1.name, t1.obs
FROM table1 t1, table2 t2, table3 t3
WHERE t1.id IN (t2.id, t3.id) AND t3.serial='Serial6';
I cannot use unions, external tables or views for this.
Please let me know in case of further questions.
Thanks a lot for your answers, I really appreciate your time..
You need to select from T2 OR T3 but never both? I think you want something like this
select count(*)
from t1
where exists (
select 'x'
from t2
where MyPrimaryKey_Name = 'random_name'
and t2.id = t1.id
)
or exists (
select 'x'
from t3
where MyPrimaryKey_Name = 'random_name'
and t3.id = t1.id
)
I'm trying write a query to find records which don't have a matching record in another table.
For example, I have a two tables whose structures looks something like this:
Table1
State | Product | Distributor | other fields
CA | P1 | A | xxxx
OR | P1 | A | xxxx
OR | P1 | B | xxxx
OR | P1 | X | xxxx
WA | P1 | X | xxxx
VA | P2 | A | xxxx
Table2
State | Product | Version | other fields
CA | P1 | 1.0 | xxxx
OR | P1 | 1.5 | xxxx
WA | P1 | 1.0 | xxxx
VA | P2 | 1.2 | xxxx
(State/Product/Distributor together form the key for Table1. State/Product is the key for Table2)
I want to find all the State/Product/Version combinations which are Not using distributor X. (So the result in this example is CA-P1-1.0, and VA-P2-1.2.)
Any suggestions on a query to do this?
SELECT
*
FROM
Table2 T2
WHERE
NOT EXISTS (SELECT *
FROM
Table1 T1
WHERE
T1.State = T2.State AND
T1.Product = T2.Product AND
T1.Distributor = 'X')
This should be ANSI compliant.
In T-SQL:
SELECT DISTINCT Table2.State, Table2.Product, Table2.Version
FROM Table2
LEFT JOIN Table1 ON Table1.State = Table2.State AND Table1.Product = Table2.Product AND Table1.Distributor = 'X'
WHERE Table1.Distributor IS NULL
No subqueries required.
Edit: As the comments indicate, the DISTINCT is not necessary. Thanks!
select * from table1 where state not in (select state from table1 where distributor = 'X')
Probably not the most clever but that should work.
SELECT DISTINCT t2.State, t2.Product, t2.Version
FROM table2 t2
JOIN table1 t1 ON t1.State = t2.State AND t1.Product = t2.Product
AND t1.Distributor <> 'X'
In Oracle:
SELECT t2.State, t2.Product, t2.Version
FROM Table2 t2, Table t1
WHERE t1.State(+) = t2.State
AND t1.Product(+) = t2.Product
AND t1.Distributor(+) = :distributor
AND t1.State IS NULL