SELECT '1000000' AS number
UNION ALL
SELECT '541' AS number
UNION ALL
SELECT '-500' AS number
UNION ALL
SELECT '100' AS number
UNION ALL
SELECT number, 'biggest' AS result
WHERE number = 1000000
How to make this work? My task is to find the biggest number from those that I added.
SELECT '1000000' AS number
UNION ALL
SELECT '541' AS number
UNION ALL
SELECT '-500' AS number
UNION ALL
SELECT '100' AS number
UNION ALL
SELECT number, 'biggest' AS result
WHERE number = 1000000
How to make this work? My task is to find the biggest number from those that I added.
You need to wrap the query in a derived table to be able access a column alias
select *
from (
SELECT 1000000 AS number
UNION ALL
SELECT 541 AS number
UNION ALL
SELECT -500 AS number
UNION ALL
SELECT 100 AS number
)
WHERE number = 1000000
But to find the highest number, you can use an order by and limit:
select *
from (
SELECT 1000000 AS number
UNION ALL
SELECT 541 AS number
UNION ALL
SELECT -500 AS number
UNION ALL
SELECT 100 AS number
)
order by number desc
limit 1
Alternatively you can also simplify this by using a VALUES clause:
select *
from (
values (1000000),(541),(-500),(100)
) as t(number)
order by number desc
limit 1
you can use common table expresssion with FETCH as given below:
WITH CTE_Number AS (
SELECT 1000000 AS number
UNION ALL
SELECT 541 AS number
UNION ALL
SELECT -500 AS number
UNION ALL
SELECT 100 AS number
)
SELECT Number,'Biggest' as result
FROM CTE_Number
ORDER BY Number DESC
FETCH FIRST ROW ONLY;
Related
I have a problem with my SQL command. I want to select 2 movies which 2 movies sum of durations less than 150 I wrote this SQL command:
Select
movie_title,Sum(movie_time) as sum_movie
From
movie_movie
Group By
movie_title
Having
Sum(movie_time)<100
Order By
sum_movie DESC
You can get two movies with minimum movie_time values with order by movie_time ASC limit 2 in CTE, and then use that in the condition.
with two_min_movie as (
select *
from movie_movie
order by movie_time ASC limit 2
)
select *
from two_min_movie
where (select sum(movie_time) from two_min_movie) < 150
Demo in DBfiddle
I have a CTE that i want to grab data from, but i want different types of data with the same limit from the same CTE according to different rules.
Example: fruit_cte -> (id::integer, name::text, q1::boolean, q2::boolean)
I could do something like:
SELECT * FROM (SELECT 1 as query_num, * FROM fruit_cte WHERE q1 ORDER BY name LIMIT 100) as ABC
UNION ALL
SELECT * FROM (SELECT 2 as query_num, * FROM fruit_cte WHERE q2 ORDER BY name LIMIT 100) as ABC
UNION ALL
SELECT * FROM (SELECT -1 as query_num, * FROM fruit_cte WHERE NOT q1 AND NOT q2 ORDER BY name LIMIT 100) as ABC
But this is very costly and would be nice to tie this up into 1 select. Is this even possible?
The last select is a nice to have to get data that doesn't meet the requirements but possible to go without.
PG version 11+
You could get it all without the CTE, by using window functions instead.
SELECT type, id, name, q1, q2
FROM (
SELECT
CASE WHEN q1 THEN 1 WHEN q2 THEN 2 ELSE -1 END AS type,
ROW_NUMBER() OVER (
PARTITION BY CASE WHEN q1 THEN 1 WHEN q2 THEN 2 ELSE -1 END
ORDER BY NAME
) AS row_number,
id,
name,
q1,
q2
FROM ...
)
WHERE row_number <= 100
The row_number() will count, sorted by name, and keep a separate tally for every type
I am stuck at this T-SQL query.
I have table below
Age SectioName Cost
---------------------
1 Section1 100
2 Section1 200
1 Section2 500
3 Section2 100
4 Section2 200
Lets say for each section I can have maximum 5 Age. In above table there are some missing Ages. How do I insert missing Ages for each section. (Possibly without using cursor). The cost would be zero for missing Ages
So after the insertion the table should look like
Age SectioName Cost
---------------------
1 Section1 100
2 Section1 200
3 Section1 0
4 Section1 0
5 Section1 0
1 Section2 500
2 Section2 0
3 Section2 100
4 Section2 200
5 Section2 0
EDIT1
I should have been more clear with my question. The maximum age is dynamic value. It could be 5,6,10 or someother value but it will be always less than 25.
I think I got it
;WITH tally AS
(
SELECT 1 AS r
UNION ALL
SELECT r + 1 AS r
FROM tally
WHERE r < 5 -- this value could be dynamic now
)
select n.r, t.SectionName, 0 as Cost
from (select distinct SectionName from TempFormsSectionValues) t
cross join
(select ta.r FROM tally ta) n
where not exists
(select * from TempFormsSectionValues where YearsAgo = n.r and SectionName = t.SectionName)
order by t.SectionName, n.r
You can use this query to select missing value:
select n.num, t.SectioName, 0 as Cost
from (select distinct SectioName from table1) t
cross join
(select 1 as num union select 2 union select 3 union select 4 union select 5) n
where not exists
(select * from table1 where table1.age = n.num and table1.SectioName = t.SectioName)
It creates a Cartesian product of sections and numbers 1 to 5 and then selects those that doesn't exist yet. You can then use this query for the source of insert into your table.
SQL Fiddle (it has order by added to check the results easier but it's not necessary for inserting).
Use below query to generate missing rows
SELECT t1.Age,t1.Section,ISNULL(t2.Cost,0) as Cost
FROM
(
SELECT 1 as Age,'Section1' as Section,0 as Cost
UNION
SELECT 2,'Section1',0
UNION
SELECT 3,'Section1',0
UNION
SELECT 4,'Section1',0
UNION
SELECT 5,'Section1',0
UNION
SELECT 1,'Section2',0
UNION
SELECT 2,'Section2',0
UNION
SELECT 3,'Section2',0
UNION
SELECT 4,'Section2',0
UNION
SELECT 5,'Section2',0
) as t1
LEFT JOIN test t2
ON t1.Age=t2.Age AND t1.Section=t2.Section
ORDER BY Section,Age
SQL Fiddle
You can utilize above result set for inserting missing rows by using EXCEPT operator to exclude already existing rows in table -
INSERT INTO test
SELECT t1.Age,t1.Section,ISNULL(t2.Cost,0) as Cost
FROM
(
SELECT 1 as Age,'Section1' as Section,0 as Cost
UNION
SELECT 2,'Section1',0
UNION
SELECT 3,'Section1',0
UNION
SELECT 4,'Section1',0
UNION
SELECT 5,'Section1',0
UNION
SELECT 1,'Section2',0
UNION
SELECT 2,'Section2',0
UNION
SELECT 3,'Section2',0
UNION
SELECT 4,'Section2',0
UNION
SELECT 5,'Section2',0
) as t1
LEFT JOIN test t2
ON t1.Age=t2.Age AND t1.Section=t2.Section
EXCEPT
SELECT Age,Section,Cost
FROM test
SELECT * FROM test
ORDER BY Section,Age
http://www.sqlfiddle.com/#!3/d9035/11
I have a table with some transaction fields, primary id is a CUSTomer field and a TXN_DATE and for two of them, NOM_AMOUNT and GRS_AMOUNT I need an EndOfMonth SUM (no rolling, just EOM, can be 0 if no transaction in the month) for these two amount fields. How can I do it? I need also a 0 reported for months with no transactions..
Thank you!
If you group by the expresion month(txn_date) you can calculate the sum. If you use a temporary table with a join on month you can determine which months have no records and thus report a 0 (or null if you don't use the coalesce fiunction).
This will be your end result, I assume you are able to add the other column you need to sum and adapt for your schema.
select mnt as month
, sum(coalesce(NOM_AMOUNT ,0)) as NOM_AMOUNT_EOM
, sum(coalesce(GRS_AMOUNT ,0)) as GRS_AMOUNT_EOM
from (
select 1 as mnt
union all select 2
union all select 3
union all select 4
union all select 5
union all select 6
union all select 7
union all select 8
union all select 9
union all select 10
union all select 11
union all select 12) as m
left outer join Table1 as t
on m.mnt = month(txn_date)
group by mnt
Here is the initial working sqlfiddle
I am teaching myself T-SQL and am struggling to comprehend the following example..
Suppose you want to display several nonaggregated columns along with
some aggregate expressions that apply to the entire result set or to a
larger grouping level. For example, you may need to display several
columns from the Sales.SalesOrderHeader table and calculate the
percent of the TotalDue for each sale compared to the TotalDue for all
the customer’s sales. If you group by CustomerID, you can’t include
other nonaggregated columns from Sales.SalesOrderHeader unless you
group by those columns. To get around this, you can use a derived
table or a CTE.
Here are two examples given...
SELECT c.CustomerID, SalesOrderID, TotalDue, AvgOfTotalDue,
TotalDue/SumOfTotalDue * 100 AS SalePercent
FROM Sales.SalesOrderHeader AS soh
INNER JOIN
(SELECT CustomerID, SUM(TotalDue) AS SumOfTotalDue,
AVG(TotalDue) AS AvgOfTotalDue
FROM Sales.SalesOrderHeader
GROUP BY CustomerID) AS c ON soh.CustomerID = c.CustomerID
ORDER BY c.CustomerID;
WITH c AS
(SELECT CustomerID, SUM(TotalDue) AS SumOfTotalDue,
AVG(TotalDue) AS AvgOfTotalDue
FROM Sales.SalesOrderHeader
GROUP BY CustomerID)
SELECT c.CustomerID, SalesOrderID, TotalDue,AvgOfTotalDue,
TotalDue/SumOfTotalDue * 100 AS SalePercent
FROM Sales.SalesOrderHeader AS soh
INNER JOIN c ON soh.CustomerID = c.CustomerID
ORDER BY c.CustomerID;
Why doesn't this query produce the same result..
SELECT CustomerID, SalesOrderID, TotalDue, AVG(TotalDue) AS AvgOfTotalDue,
TotalDue/SUM(TotalDue) * 100 AS SalePercent
FROM Sales.SalesOrderHeader
GROUP BY CustomerID, SalesOrderID, TotalDue
ORDER BY CustomerID
I'm looking for someone to explain the above examples in another way or step through it logically so I can understand how they work?
The aggregates in this statement (i.e. SUM and AVG) don't do anything:
SELECT CustomerID, SalesOrderID, TotalDue, AVG(TotalDue) AS AvgOfTotalDue,
TotalDue/SUM(TotalDue) * 100 AS SalePercent
FROM Sales.SalesOrderHeader
GROUP BY CustomerID, SalesOrderID, TotalDue
ORDER BY CustomerID
The reason for this is you're grouping by TotalDue, so all records in the same group have the same value for this field. In the case of AVG this means you're guarenteed for AvgOfTotalDue to always equal TotalDue. For SUM it's possible you'd get a different result, but as you're also grouping by SalesOrderID (which I'd imagine is unique in the SalesOrderHeader table) you will only have one record per group, so again this will always equal the TotalDue value.
With the CTE example you're only grouping by CustomerId; as a customer may have many sales orders associated with it, these aggregate values will be different to the TotalDue.
EDIT
Explanation of the aggregate of field included in group by:
When you group by a value, all rows with that same value are collected together and aggregate functions are performed over them. Say you had 5 rows with a total due of 1 and 3 with a total due of 2 you'd get two result lines; one with the 1s and one with the 2s. Now if you perform a sum on these you have 3*1 and 2*2. Now divide by the number of rows in that result line (to get the average) and you have 3*1/3 and 2*2/2; so things cancel out leaving you with 1 and 2.
select totalDue, avg(totalDue)
from (
select 1 totalDue
union all select 1 totalDue
union all select 1 totalDue
union all select 2 totalDue
union all select 2 totalDue
) x
group by totalDue
select uniqueId, totalDue, avg(totalDue), sum(totalDue)
from (
select 1 uniqueId, 1 totalDue
union all select 2 uniqueId, 1 totalDue
union all select 3 uniqueId, 1 totalDue
union all select 4 uniqueId, 2 totalDue
union all select 5 uniqueId, 2 totalDue
) x
group by uniqueId
Runnable Example: http://sqlfiddle.com/#!2/d41d8/21263