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
Related
i have a table where
patientId | Units | Amount | PatientName
1234 | 1 | 20 |lisa
1111 | 5 | 10 |john
1234 | 10 | 200 |lisa
345 | 2 | 30 | xyz
i want to get ID in one column, then patient name then total amount spent by him on different items,
please note i have got patient name in the column above by doing a join on 2 tables using ID as the key
i am doing this to get this table
select t1.*,t2.name from table1 as t1 inner join table2 as t2
on t1.id = t2.id
then for adding i am trying to use the group by clause but that gives an error
please note i cannot use temp table in this, only need to do this using subquery, how to do it?
Are you looking for group by?
select t1.patientid, t2.patientname, sum(t1.amount)
from table1 t1 join
table2 t2
on t1.id = t2.id
group by t1.patientid, t2.patientname;
select t1.*,
t2.name
from table1 t1
inner join table2 t2
on t1.id = t2.id
group by t1.id, t2.name
What are table1 and table2 like? What's the error message?
I have two tables
Table 1
ID | T1_Date
---+-------------
1 | 09/08/2020
2 | 09/30/2020
Table 2
T2_Date | Label
-----------+-----
08/31/2020 | Aug-20
09/20/2020 | Sep-20
10/25/2020 | Oct-20
I'm trying to have the result link the nearest future date label from table 2 with each record in table 1. So my output would look like:
ID | T1_Date | Label
---+------------+--------
1 | 09/08/2020 | Sep-20
2 | 09/30/2020 | Oct-20
So far I can only return all the records that are greater than the T1_Date value, so it repeats all the labels.
Is there a way to just grab the nearest future date label or the equal to label?
One method is a correlated subquery:
select t1.*,
(select max(t2.label) keep (dense_rank first t2.date asc)
from t2
where t2.date > t1.date
)
from t1;
there are many ways, you can solve this problem
One way which is pretty simple but not optimal:
select
t1.*
,(select Label from table2 where t2_date=(select MIN(T2_Date)from table2
where T2_Date>=T1_Date))Label
from table1 t1
-----------------------------------------------------------
The second Way:
with TempTable as
(
select T1_Date,min(T2_Date)T2_Date
from table2
left join table1 on T2_Date>=T1_Date
group by T1_Date
)
select t1.T1_Date,t2.Label from TempTable temp
left join table1 t1 on t1.T1_Date=temp.T1_Date
left join table2 t2 on t2.T2_Date=temp.T2_Date
------------------
| **table 1** |
------------------
| 1 | 400 |
| 2 | 220 |
| 3 | 123 |
------------------
| **table 2** |
------------------
| 1 | 100 |
formula : table1 - table2 where table1.id=table2.id
------------------
| **Result** |
------------------
| 1 | 300 |
| 2 | 220 |
| 3 | 123 |
You want an outer join to get all rows from table_1 and the matching ones from table2
select t1.id, t1.val - coalesce(t2.val, 0) as result
from table_1 t1
left join table_2 t2 on t1.id = t2.id;
The coalesce(t2.val, 0) is necessary because the outer join will return null for those rows where no id exists in table_2 but t1.val - null would yield null
select t1.id,
nvl2(t2.val,t1.val-t2.val,t1.val) val
from t1,t2
where t1.id=t2.id(+)
order by t1.id;
Try this
select t1.col1, t1.col2-t2.col1 as balance from
table1 t1 left join table2 t2 on t1.col1=t2.col1
I don't the syntax in Oracle sql, but I can give the solution in mysql.
Consider the table with 2 columns:
id , value
SELECT table1.id, table1.value - table2.value
FROM table1, table2
WHERE table1.id=table2.id
OR
SELECT table1.id, table1.value
FROM table1, table2
WHERE NOT (table1.id =table2.id)
In some cases using scalar subquery caching could give better performance. It is on developer to compare execution plans and decide which query is the most appropriate.
with t1 (id, num) as
(
select 1, 400 from dual union all
select 2, 220 from dual union all
select 3, 123 from dual
),
t2(id, num) as
(
select 1, 100 from dual
)
select id,
num - nvl((select num from t2 where t2.id = t1.id), 0) result
from t1;
This is just to show you a different technique for solving problems in which you try to get data from several tables, but some may not have matching rows.
Using outer join in this case is in my opinion more logical.
I have a table with this structure:
Table 1: ID(PK) | <other columns>
1 | otherdata
2 | otherdata
the other table, It´s a list of documents (PDF,DOC,etc) with a URL to download. these documents is stored in my network.
Table 2: ID | IDDOC | LINKDOC | INFO
1 | 1 | 'http://URL1' | 'Info1'
1 | 2 | 'http://URL2' | 'Info2'
2 | 1 | 'http://URL3' | 'Info3'
ID is the foreign key for Table 1,IDDOC is a foreign key to a 3rd table (below) that describe the document type:
Table 3: IDDOC | Name
1 | 'Contract'
2 | 'Notification'
I need to generate a query to join these tables and get a similar structure
ID | <SomeCollumsTable1> | NameDesc1 | NameURL1 | ... | NameDesc2 | NameURL2
Example output:
ID | <SomeCollumsTable1> | ContractDesc | ContractURL | NotificationDesc | NotificationURL
1 | otherdata | 'Info1' | 'http://URL1' | 'Info2' | 'http://URL2'
2 | otherdata | 'Info3' | 'http://URL3' | '' | ''
I.E. Generate many pairs Desc/URL as many records exits in "Table3". the sample data have 2 documents types and generate 4 columns.
Currently i have subquerys to each desired document, but sounds very inefficient for me, the query is big and new documents i add in "Table3" need change in the whole query and need to just adjust the Where clause to indicate why IDDOC´s need. (using a IN clause)
Or its better to manipulate this in my application (winforms/vb.net)?
The App generate a report in EXCEL format.
Please try the below query:
DECLARE #qu NVARCHAR(MAX), #pcol NVARCHAR(MAX)
SELECT #pcol= COALESCE(#pcol + ',','') + type FROM
(SELECT Name+N'URL' AS type FROM t3 UNION SELECT Name+N'Desc' AS type FROM t3 ) A
SET #qu=N'Select ID,b,c,'+ #pcol + N' FROM
(
SELECT t1.ID, t1.b,t1.c, t2.linkdoc as data,t3.Name +N''URL'' as Type FROM t1 LEFT JOIN t2 ON t1.ID=t2.ID
LEFT JOIN t3 ON t2.iddoc=t3.iddoc
UNION
SELECT t1.ID, t1.b, t1.c, t2.info as data, t3.Name +N''Desc'' as Type FROM t1 LEFT JOIN t2 ON t1.ID=t2.ID
LEFT JOIN t3 ON t2.iddoc=t3.iddoc
)S
PIVOT
(
MAX(data)
FOR Type IN ('+#pcol +N')) AS piv'
EXEC sp_executesql #qu
Here's a sql fiddle for you :
http://sqlfiddle.com/#!6/9fb46/1
EDIT:explanation added
So basically I am using PIVOT, except that PIVOT can be done on a
single column , in our case, either on URL or Desc columns. But we
need both these columns to be pivoted,so I used UNION to get both into
a single column data like below
SELECT t1.ID, t1.b,t1.c, t2.linkdoc as data,t3.Name +N'URL' as Type FROM t1 LEFT JOIN t2 ON t1.ID=t2.ID
LEFT JOIN t3 ON t2.iddoc=t3.iddoc
UNION
SELECT t1.ID, t1.b, t1.c, t2.info as data, t3.Name +N'Desc' as Type FROM t1 LEFT JOIN t2 ON t1.ID=t2.ID
LEFT JOIN t3 ON t2.iddoc=t3.iddoc
which I then used in PIVOT like this :
Select ID,b,c,[ContractURL],[ContractDesc],[NotificationURL],[NotificationDesc]
FROM
(
SELECT t1.ID, t1.b,t1.c, t2.linkdoc as data,t3.Name +N'URL' as Type FROM t1 LEFT JOIN t2 ON t1.ID=t2.ID
LEFT JOIN t3 ON t2.iddoc=t3.iddoc
UNION
SELECT t1.ID, t1.b, t1.c, t2.info as data, t3.Name +N'Desc' as Type FROM t1 LEFT JOIN t2 ON t1.ID=t2.ID
LEFT JOIN t3 ON t2.iddoc=t3.iddoc
)S
PIVOT
(
MAX(data)
FOR Type IN ([ContractURL],[ContractDesc],[NotificationURL],[NotificationDesc])
)piv
Now for making this dynamic I calculated all the unique columns from table t3 like
SELECT Name+N'URL' AS type FROM t3 UNION SELECT Name+N'Desc' AS type FROM t3
Lets say I have a table1:
id name
-------------
1 "one"
2 "two"
3 "three"
And a table2 with a foreign key to the first:
id tbl1_fk option value
-------------------------------
1 1 1 1
2 2 1 1
3 1 2 1
4 3 2 1
Now I want to have as a query result:
table1.id | table1.name | option | value
-------------------------------------
1 "one" 1 1
2 "two" 1 1
3 "three"
1 "one" 2 1
2 "two"
3 "three" 2 1
How do I achieve that?
I already tried:
SELECT
table1.id,
table1.name,
table2.option,
table2.value
FROM table1 AS table1
LEFT outer JOIN table2 AS table2 ON table1.id = table2.tbl1fk
but the result seems to omit the null vales:
1 "one" 1 1
2 "two" 1 1
1 "one" 2 1
3 "three" 2 1
SOLVED: thanks to Mahmoud Gamal: (plus the GROUP BY)
Solved with this query
SELECT
t1.id,
t1.name,
t2.option,
t2.value
FROM
(
SELECT t1.id, t1.name, t2.option
FROM table1 AS t1
CROSS JOIN table2 AS t2
) AS t1
LEFT JOIN table2 AS t2 ON t1.id = t2.tbl1fk
AND t1.option = t2.option
group by t1.id, t1.name, t2.option, t2.value
ORDER BY t1.id, t1.name
You have to use CROSS JOIN to get every possible combination of name from the first table with the option from the second table. Then LEFT JOIN these combination with the second table. Something like:
SELECT
t1.id,
t1.name,
t2.option,
t2.value
FROM
(
SELECT t1.id, t1.name, t2.option
FROM table1 AS t1
CROSS JOIN table2 AS t2
) AS t1
LEFT JOIN table2 AS t2 ON t1.id = t2.tbl1_fk
AND t1.option = t2.option
SQL Fiddle Demo
Simple version: option = group
It's not specified in the Q, but it seems like option is supposed to define a group somehow. In this case, the query can simply be:
SELECT t1.id, t1.name, t2.option, t2.value
FROM (SELECT generate_series(1, max(option)) AS option FROM table2) o
CROSS JOIN table1 t1
LEFT JOIN table2 t2 ON t2.option = o.option AND t2.tbl1_fk = t1.id
ORDER BY o.option, t1.id;
Or, if options are not numbered in sequence, starting with 1:
...
FROM (SELECT DISTINCT option FROM table2) o
...
Returns:
id | name | option | value
----+-------+--------+-------
1 | one | 1 | 1
2 | two | 1 | 1
3 | three | |
1 | one | 2 | 1
2 | two | |
3 | three | 2 | 1
Faster and cleaner, avoiding the big CROSS JOIN and the big GROUP BY.
You get distinct rows with a group number (grp) per set.
Requires Postgres 8.4+.
More complex: group indicated by sequence of rows
WITH t2 AS (
SELECT *, count(step OR NULL) OVER (ORDER BY id) AS grp
FROM (
SELECT *, lag(tbl1_fk, 1, 2147483647) OVER (ORDER BY id) >= tbl1_fk AS step
FROM table2
) x
)
SELECT g.grp, t1.id, t1.name, t2.option, t2.value
FROM (SELECT generate_series(1, max(grp)) AS grp FROM t2) g
CROSS JOIN table1 t1
LEFT JOIN t2 ON t2.grp = g.grp AND t2.tbl1_fk = t1.id
ORDER BY g.grp, t1.id;
Result:
grp | id | name | option | value
-----+----+-------+--------+-------
1 | 1 | one | 1 | 1
1 | 2 | two | 1 | 1
1 | 3 | three | |
2 | 1 | one | 2 | 1
2 | 2 | two | |
2 | 3 | three | 2 | 1
-> SQLfiddle for both.
How?
Explaining the complex version ...
Every set is started with a tbl1_fk <= the last one. I check for this with the window function lag(). To cover the corner case of the first row (no preceding row) I provide the biggest possible integer 2147483647 the default for lag().
With count() as aggregate window function I add the running count to each row, effectively forming the group number grp.
I could get a single instance for every group with:
(SELECT DISTINCT grp FROM t2) g
But it's faster to just get the maximum and employ the nifty generate_series() for the reduced CROSS JOIN.
This CROSS JOIN produces exactly the rows we need without any surplus. Avoids the need for a later GROUP BY.
LEFT JOIN t2 to that, using grp in addition to tbl1_fk to make it distinct.
Sort any way you like - which is possible now with a group number.
try this
SELECT
table1.id, table1.name, table2.option, table2.value FROM table1 AS table11
JOIN table2 AS table2 ON table1.id = table2.tbl1_fk
This is enough:
select * from table1 left join table2 on table1.id=table2.tbl1_fk ;