I am a beginner in SQL and unfortunately I am not being able to solve a problem. I have a list of column names in a system table which I want to insert into separate rows of a table based on the serial of the column name.
Original table:
Column name
001000
001100
001200
002000
002100
002200
002300
Target table:
Column 1
Column 2
Column 3
Column 4
001000
001100
001200
NULL
002000
002100
002200
002300
......
......
......
......
022000
022100
022200
022300
There are a large number of rows in the original table so it is quite challenging to separate the numbers into groups. I have looked into the PIVOT function but that does not solve this issue.
Unfortunately, as I am a beginner, I am also not able to put it into code to begin with. Any help with recommending which functions I should look into so that I can start writing some code on this would be really helpful. Any pointers towards a solution is also highly appreciated.
Conditional aggregation should do what you want:
select max(case when seqnum = 1 then column end),
max(case when seqnum = 2 then column end),
max(case when seqnum = 3 then column end),
max(case when seqnum = 4 then column end)
from (select t.*,
row_number() over (partition by left(column, 3) order by column) as seqnum
from t
) t
group by left(column, 3)
Related
I need to count the number of rows that fulfill certain conditions contained in intervals defined by other rows that fulfill other conditions. Examples: the number of rows N between 'Reference' having values 1 and 4 that fulfill the condition 'Other_condition' = b is N=1, the number of rows N between 'Reference' having values 2 and 5 that fulfill the condition 'Other_condition' = b is N=2 etc.
Date Reference Other_condition
20171111 1 a
20171112 2 a
20171113 3 b
20171114 4 b
20171115 5 b
I'm accessing the database through Hive/Impala SQL queries and unfortunately I have no idea where to start implementing such a window function. A half-pseudocode version of what I want would be something like:
SELECT COUNT (DISTINCT database.Date) AS counter, Other_condition, reference
FROM database
WHERE database.Other_condition = a AND database.Reference BETWEEN
(window function condition 1: database.Reference = 2) AND
(window function condition 2: database.Reference = 5)
GROUP BY counter
Your question is rather hard to follow. I get the first conditions, which is the number of rows between "1" and "4".
Here is one method that should be pretty easy to generalize:
select (max(case when reference = 4 then seqnum end) -
max(case when reference = 1 then seqnum end)
) as num_rows_1_4
from (select t.*,
row_number() over (order by date) as seqnum
from t
) t;
I have a table which has the following content:
Customer ID Customer type
--------- --------
123 A
123 alpha
123 Beta
456 B
456 BGamma
456 BBeta
I want to achieve the following:
Customer_ID Customer_type Customer_E1 Customer E_2 Customer E_3
--------- ----------- ----------- ------------- -------------
123 A Alpha Beta
456 B BGamma BBeta
Can you please help me with a Sybase query to achieve this?
I don't believe Sybase has a PIVOT function which is what you are trying to do. So you might be able to implement something like this which uses an aggregate function with a CASE statement:
select customerid,
max(case when rn = 1 then customertype else null end) CustomerType,
max(case when rn = 2 then customertype else null end) Customer_E1,
max(case when rn = 3 then customertype else null end) Customer_E2
from
(
select CustomerID, CustomerType,
row_number() over(partition by CustomerID order by CustomerID) rn
from yourtable
) src
group by customerid
See SQL Fiddle with Demo
Note: I see a potential issue with the first column of data CustomerType. My suggestion would be to have this in a separate column from the other values. Then this will not take part in the row_number() assignment and it will be easier to guarantee that the correct value will appear.
Let me suggest that you normalize your data model. Clearly 'A' vs 'Alpha' are different kinds of data values (they describe different things), but you have them in the same field, which is causing you all sorts of problems. Take a look at this article on database normalization, which has a good discussion of the concepts involved.
Basically, what you want to end up with is having alpha and beta type values in a separate table that you can key into via Customer ID and Customer Type.
please help me i have columns from more than one table and the data type for all these columns is integer
i want to sort the data row (not columns (not order by)) Except the primary key column
for example
column1(pk) column2 column3 column4 column5
1 6 5 3 1
2 10 2 3 1
3 1 2 4 3
How do I get this result
column1(pk) column2 column3 column4 column5
1 1 3 5 6
2 1 2 3 10
3 1 2 3 4
Please help me quickly .. Is it possible ?? or impossible ???
if impossible how I could have a similar result regardless of sort
What database are you using? The capabilities of the database are important. Second, this suggests a data structure issue. Things that need to be sorted would normally be separate entities . . . that is, separate rows in a table. The rest of this post answers the question.
If the database supports pivot/unpivot you can do the following:
(1) Unpivot the data to get in the format , ,
(2) Use row_number() to assign a new column, based on the ordering of the values.
(3) Use the row_number() to create a varchar new column name.
(4) Pivot the data again using the new column.
You can do something similar if this functionality is not available.
First, change the data to rows:
(select id, 'col1', col1 as val from t) union all
(select id, 'col2', col2 from t) union all
. . .
Call this byrow. The following query appends a row number:
select br.*, row_number() over (partition by id order by val) as seqnum
from byrow br
Put this into a subquery to unpivot. The final solution looks like:
with byrow as (<the big union all query>)
select id,
max(case when seqnum = 1 then val end) as col1,
max(case when seqnum = 2 then val end) as col2,
...
from (select br.*, row_number() over (partition by id order by val) as seqnum
from byrow br
) br
group by id
You can use pivot function of sql server to convert the row in column. Apply the sorting there and again convert column to row using unpivot.
Here is a good example using PIVOT, you should be able to adapt this to meet your needs
http://blogs.msdn.com/b/spike/archive/2009/03/03/pivot-tables-in-sql-server-a-simple-sample.aspx
I have a survey database with one column for each question and one row for each person who responds. Each question is answered with a value from 1 to 3.
Id Quality? Speed?
-- ------- -----
1 3 1
2 2 1
3 2 3
4 3 2
Now, I need to display the results as one row per question, with a column for each response number, and the value in each column being the number of responses that used that answer. Finally, I need to calculate the total score, which is the number of 1's plus two times the number of 2's plus three times the number of threes.
Question 1 2 3 Total
-------- -- -- -- -----
Quality? 0 2 2 10
Speed? 2 1 1 7
Is there a way to do this in set-based SQL? I know how to do it using loops in C# or cursors in SQL, but I'm trying to make it work in a reporting tool that doesn't support cursors.
This will give you what you're asking for:
SELECT
'quality' AS question,
SUM(CASE WHEN quality = 1 THEN 1 ELSE 0 END) AS [1],
SUM(CASE WHEN quality = 2 THEN 1 ELSE 0 END) AS [2],
SUM(CASE WHEN quality = 3 THEN 1 ELSE 0 END) AS [3],
SUM(quality)
FROM
dbo.Answers
UNION ALL
SELECT
'speed' AS question,
SUM(CASE WHEN speed = 1 THEN 1 ELSE 0 END) AS [1],
SUM(CASE WHEN speed = 2 THEN 1 ELSE 0 END) AS [2],
SUM(CASE WHEN speed = 3 THEN 1 ELSE 0 END) AS [3],
SUM(speed)
FROM
dbo.Answers
Keep in mind though that this will quickly balloon as you add questions or even potential answers. You might be much better off if you normalized a bit and had an Answers table with a row for each answer with a question code or id, instead of putting them across as columns in one table. It starts to look a little bit like the entity-value pair design, but I think that it's different enough to be useful here.
You can also leverage SQL 2005's pivoting functions to achieve what you want. This way you don't need to hard code any questions as you do in cross-tabulation. Note that I called the source table "mytable" and I used common table expressions for readability but you could also use subqueries.
WITH unpivoted AS (
SELECT id, value, question
FROM mytable a
UNPIVOT (value FOR question IN (quality,speed) ) p
)
,counts AS (
SELECT question, value, count(*) AS counts
FROM unpivoted
GROUP BY question, value
)
, repivoted AS (
SELECT question, counts, [1], [2], [3]
FROM counts
PIVOT (count(value) FOR value IN ([1],[2],[3])) p
)
SELECT question, sum(counts*[1]) AS [1], sum(counts*[2]) AS [2], sum(counts*[3]) AS [3]
,sum(counts*[1]) + 2*sum(counts*[2]) + 3*sum(counts*[3]) AS Total
FROM repivoted
GROUP BY question
Note if you don't want the breakdown the query is simpler:
WITH unpivoted AS (
SELECT id, value, question
FROM mytable a
UNPIVOT (value FOR question IN (quality,speed) ) p
)
, totals AS (
SELECT question, value, count(value)*value AS score
FROM unpivoted
GROUP BY question, value
)
SELECT question, sum(score) AS score
FROM totals
GROUP BY question
What I am looking for is to group by and count the total of different data in the same table and have them show in two different columns. Like below.
Data in table A
Fields:
Name Type
Bob 1
John 2
Bob 1
Steve 1
John 1
Bob 2
Desired result from query:
Name Type 1 Type 2
Bob 2 1
John 1 1
Steve 1 0
This will do the trick in SQL Server:
SELECT
name,
SUM( CASE type WHEN 1 THEN 1 ELSE 0 END) AS type1,
SUM( CASE type WHEN 2 THEN 1 ELSE 0 END) AS type2
FROM
myTable
GROUP BY
name
No time to write the code, but the Case statement is what you want here. SImply havea value of 1 if it meets the case and zero if it deosn't. Then you can sum the columns.
Use two separate GROUP BY subqueries.
SELECT Name, a.Count1, b.Count2
from myTable
JOIN
(SELECT Name, SUM(Type) AS Count1 FROM myTable GROUP BY Name WHERE Type=1) AS a ON a.Name = myTable.Name
(SELECT Name, SUM(Type) FROM myTable GROUP BY Name WHERE Type=2) AS b ON b.Name = myTable.Name
You're looking for a CrossTab solution. The above solutions will work, but you'll come unstuck if you want a general solution and have N types.
A CrossTab solution will solve this for you. If this is for quickly crunching some numbers then dump your data into Excel and use the native Pivot Table feature.
If it's for a RDBMS in an app, then it depends upon the RDBMS. MS SQL 2005 and above has a crosstab syntax. See:
http://www.databasejournal.com/features/mssql/article.php/3521101/Cross-Tab-reports-in-SQL-Server-2005.htm
#Seb has a good solution, but it's server-dependent. Here's an alternate using subselects that should be portable:
select
name,
(select count(type) from myTable where type=1 and name=a.name) as type1,
(select count(type) from myTable where type=2 and name=a.name) as type2
from
myTable as a
group by
name