Well, I have a number which stored in a column. If I want to divide the value, I just need:
select columnName / 12 from myTable
Is it possible to put the result into 12 column? I want to make the 12 is flexible. So for instance, if I divide the value by 4, so the result should be 4 column.
Value Result1 Result2 Result3 Result4
12000 3000 3000 3000 3000
Does anyone know how to achieve this?
Thank you.
This achievable using dynamic query.
declare #cols nvarchar(max);
declare #sql nvarchar(1000);
with cte as (
select 12000 as col1, 12000/4 as col2
union all
select col1-col2, col2 from cte where col1 > col2
)
select #cols =
STUFF((select N',' + QUOTENAME(col2) from cte
FOR XML PATH('')
), 1, 1, '') + N'';
select #cols
You can avoid dynamic SQL if you know a maximum count:
Start with a mockup-table to simulate your issue
DECLARE #tbl TABLE(InitialValue DECIMAL(16,4));
INSERT INTO #tbl VALUES(12000),(20000),(10000);
--To test this I use a divisor of 4, try with other numbers
DECLARE #divisor DECIMAL(16,4)=4;
--This is the query
SELECT p.*
FROM
(
SELECT t.InitialValue / #divisor As DivResult
,t.InitialValue
,CONCAT('div',FORMAT(A.Nmbr,'00')) AS ColumnName
FROM #tbl t
CROSS APPLY(SELECT TOP(CAST(#divisor AS INT)) ROW_NUMBER() OVER(ORDER BY (SELECT NULL)) FROM master..spt_values) A(Nmbr)
) t
PIVOT
(MAX(DivResult) FOR ColumnName IN(div01,div02,div03,div04,div05,div06,div07 /*add as many as you might need*/)) p;
The result
InitialValue div01 div02 div03 div04 div05 div06 div07
10000.0000 2500.000000000000000000000 2500.000000000000000000000 2500.000000000000000000000 2500.000000000000000000000 NULL NULL NULL
12000.0000 3000.000000000000000000000 3000.000000000000000000000 3000.000000000000000000000 3000.000000000000000000000 NULL NULL NULL
20000.0000 5000.000000000000000000000 5000.000000000000000000000 5000.000000000000000000000 5000.000000000000000000000 NULL NULL NULL
As you can see, the unused columns are returned but stay NULL.
I'd prefer this approach over dynamic sql as the consumer is better of in most cases if the result set and its structure is fixed and predictable...
Hint: You can add the divisor to your result set if needed...
It has to be dynamic query
Check below
Create TABLE Table1 (Origional int)
Declare #DivisonValue INT = 4
insert into Table1
VALUES (12000)
--Change the Top (12) to you what ever number you like. this will be your total number of columns
DECLARE #Columns VARCHAR(MAX) = (SELECT
',' + C.ColumnName + ' = Origional / ' + CAST(#DivisonValue AS VARCHAR(5))
/* Above line which you need to change for division */
FROM
(SELECT TOP (#DivisonValue)
ColumnId = ROW_NUMBER() OVER (ORDER BY s1.[object_id])
,ColumnName ='Result' + CONVERT(VARCHAR(10), ROW_NUMBER() OVER (ORDER BY s1.[object_id]))
FROM sys.all_objects AS s1 CROSS JOIN sys.all_objects AS s2
) AS C
ORDER BY
C.ColumnId
FOR XML PATH (''))
DECLARE #FullQuery VARCHAR(MAX) = 'SELECT Origional,'+ substring(#Columns,2,LEN(#Columns)-1) + ' FROM Table1'
EXEC (#FullQuery)
DROP TABLE table1
GO
Change the logic as per your need for division.
Related
I have a query that returns a row
SELECT *
FROM table
WHERE id = 1;
I want to save the result into a nvarchar sql variable. I have seen similar questions Convert SQL Server result set into string but they only use select with the name of the columns, never with *.
select *
from table
where id = 1
for xml path ('')
However the answer is <column1>value1</column1> <column2>value2</column2> and I just want it to be value1, value2
Is there a way to achieve this? thank you!
If open to a helper function.
This will convert virtually any row, table or query to a string (delimited or not).
In the following examples I selected a PIPE delimiter with a CRLF line terminator.
Please note the usage and placement of _RN when a line terminator is required. Also note the ,ELEMENTS XSINIL ... this will included null values as empty string. If you want to exclude null values, simply omit the ,ELEMENTS XSINIL
Example as Entire Table or dbFiddle
Declare #YourTable Table (id int,[col_1] varchar(50),[col_2] varchar(50),[col_3] varchar(50),[col_n] varchar(50)) Insert Into #YourTable Values
(1,'data1','data2','data3','data4')
,(2,'data5','data6','data7','data8')
-- Entire Table
Declare #XML xml = (Select *,_RN=Row_Number() over (Order By (Select null)) From #YourTable for XML RAW,ELEMENTS XSINIL )
Select [dbo].[svf-str-Data-To-Delimited]('|',char(13)+char(10),#XML)
Returns
1|data1|data2|data3|data4
2|data5|data6|data7|data8
Example as Row Based
Select A.ID
,AsAString = [dbo].[svf-str-Data-To-Delimited]('|',char(13)+char(10),B.XMLData)
From #YourTable A
Cross Apply ( values ( (select a.* for xml RAW,ELEMENTS XSINIL )) )B(XMLData)
Returns
ID AsAString
1 1|data1|data2|data3|data4
2 2|data5|data6|data7|data8
The Function if Interested
CREATE Function [dbo].[svf-str-Data-To-Delimited] (#Delim varchar(50),#EOL varchar(50),#XML xml)
Returns varchar(max)
Begin
Return(
Select convert(nvarchar(max),(
Select case when Item='_RN' then ''
else case when nullif(lead(Item,1) over (Order by Seq),'_RN') is not null
then concat(Value,#Delim)
else concat(Value,#EOL)
end
end
From (
Select Seq = row_number() over(order by (select null))
,Item = xAttr.value('local-name(.)', 'nvarchar(100)')
,Value = xAttr.value('.','nvarchar(max)')
From #XML.nodes('/row/*') xNode(xAttr)
) A
Order By Seq
For XML Path (''),TYPE).value('.', 'nvarchar(max)') )
)
End
You can easily store the result as an XML string:
select *
from (values (1, 'x', getdate())) v(id, a, b)
where id = 1
for xml path ('');
Or as a JSON string:
select *
from (values (1, 'x', getdate())) v(id, a, b)
where id = 1
for json auto;
If you don't mind Using dynamic SQL (and INFORMATION_SCHEMA dictionary), for example, for SQL Server this works:
DECLARE #sql nvarchar(max) = '',
#result nvarchar(max),
#id int = 1
SELECT #sql += '+'',''+convert(nvarchar,' + QUOTENAME(column_name) +')' from INFORMATION_SCHEMA.columns where table_name = 'Student'
SET #sql = 'select #result=' + stuff(#sql,1,5,'') + ' from student where id = ' + CAST(#id as nvarchar)
EXECUTE sp_executesql #sql, N'#result nvarchar(max) OUTPUT', #result=#result OUTPUT
SELECT #result as MyOutput
I have the following SQL Server query which cranks out a comma delimited list into one field.
Result looks like this 2003, 9083, 4567, 3214
Question: What would be the best way (SQL syntax) to put this into columns?
Meaning, I need these to show up as 1 column for "2003", 1 column for "9083" 1 column, for "4567" ..etc.
Obviously the number of columns would be dynamic based on the policy ID I give it . Any idea would be most appreciated.
My query is below .
SELECT DISTINCT x.ClassCode + ', '
FROM PremByClass x
WHERE x.PolicyId = 1673885
FOR XML PATH('')
If you take out the XML and the comma you are left with
SELECT DISTINCT x.ClassCode
FROM PremByClass x
WHERE x.PolicyId = 1673885
Which gives you a single column of the values, to turn this into columns you need to PIVOT it. However, you need to specify the names of the columns.
There is some more information in this answer https://stackoverflow.com/a/15931734/350188
You need PIVOT and if number of values could be different - dynamic SQL:
SELECT *
FROM (
SELECT DISTINCT ClassCode,
ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) RN
FROM PremByClass
WHERE PolicyId = 1673885
) as t
PIVOT (
MAX(ClassCode) FOR RN IN ([1],[2],[3],[4])
) as pvt
Will give you:
1 2 3 4
-----------------------------
2003 9083 4567 3214
Dynamic SQL will be something like:
DECLARE #sql nvarchar(max),
#columns nvarchar(max)
SELECT #columns = STUFF((
SELECT DISTINCT ','+QUOTENAME(ROW_NUMBER() OVER (ORDER BY (SELECT NULL)))
FROM PremByClass
WHERE PolicyId = 1673885
FOR XML PATH('')
),1,1,'')
SELECT #sql = N'
SELECT *
FROM (
SELECT DISTINCT ClassCode,
ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) RN
FROM PremByClass
WHERE PolicyId = 1673885
) as t
PIVOT (
MAX(ClassCode) FOR RN IN ('+#columns+')
) as pvt'
EXEC sp_executesql #sql
Assuming that there's a limit to the amount of numbers in that csv string.
You could cast or convert it to an xml type, and then put the values in as many columns you expect.
In this example it's assumed that there's no more than 6 values in the text:
declare #PolicyId INT = 1673885;
select PolicyId
,x.value('/x[1]','int') as n1
,x.value('/x[2]','int') as n2
,x.value('/x[3]','int') as n3
,x.value('/x[4]','int') as n4
,x.value('/x[5]','int') as n5
,x.value('/x[6]','int') as n6
from (
select
PolicyId,
cast('<x>'+replace(ClassCode,',','</x><x>')+'</x>' as xml) as x
from PremByClass
where PolicyId = #PolicyId
) q;
I'm trying to split a column, in SQL, into multiple columns.
My data looks like this:
Column1 | Column2 | Column3
ABC | 123 | User7;User9
nbm | qre | User1;User2;User3
POI | kjh | User1;User4;User5;User9
I need to split the Column3 into 4 new columns - each column containing the first "User". Each value within this column is separated by a semi-colon. One of the problems I have is that Column3 can have any number of users listed (all separated by semi-colons), so I don't know how many "new" columns I would need added.
The final output would need to look like:
Column1 | Column2 | Column3 | NewColumn1 | NewColumn2 | ETC.
Besides the fact that this is bad design here is a solution:
Just paste this into an empty query window and execute. Adapt to your needs...
declare #tbl TABLE(Column1 VARCHAR(15),Column2 VARCHAR(15),Column3 VARCHAR(150));
INSERT INTO #tbl VALUES
('ABC','123','User7;User9')
,('nbm','qre','User1;User2;User3')
,('POI','kjh','User1;User4;User5;User9');
WITH Splitted AS
(
SELECT Column1,Column2,CAST('<x>'+REPLACE(Column3,';','</x><x>')+'</x>' AS XML) AS Col3Splitted
FROM #tbl
)
SELECT Column1,Column2,Col3Splitted
,Col3Splitted.value('x[1]','varchar(max)') AS Column4
,Col3Splitted.value('x[2]','varchar(max)') AS Column5
,Col3Splitted.value('x[3]','varchar(max)') AS Column6
,Col3Splitted.value('x[4]','varchar(max)') AS Column7
/*Add as many as you need*/
FROM Splitted
Following the discussion with #SeanLang I add this dynamic approach. It will count the highest number of semicolons in Column3 and build the statement above dynamically.
CREATE TABLE #tbl (Column1 VARCHAR(15),Column2 VARCHAR(15),Column3 VARCHAR(150));
INSERT INTO #tbl VALUES
('ABC','123','User7;User9')
,('nbm','qre','User1;User2;User3')
,('POI','kjh','User1;User4;User5;User9');
DECLARE #sql VARCHAR(MAX)=
'WITH Splitted AS
(
SELECT Column1,Column2,CAST(''<x>''+REPLACE(Column3,'';'',''</x><x>'')+''</x>'' AS XML) AS Col3Splitted
FROM #tbl
)
SELECT Column1,Column2';
DECLARE #counter INT = 0;
WHILE #counter<=(SELECT MAX(LEN(Column3) - LEN(REPLACE(Column3, ';', ''))) from #tbl)
BEGIN
SET #counter=#counter+1;
SET #sql=#sql+',Col3Splitted.value(''x[' + CAST(#counter AS VARCHAR(10)) + ']'',''varchar(max)'') AS Column' + CAST(#counter+3 AS VARCHAR(10));
END
SET #sql=#sql+ ' FROM Splitted;';
EXEC (#sql);
DROP TABLE #tbl;
Here is a method that will be 100% dynamic. It will produce any number of columns based solely on the data it finds. The prevailing method for this around SO is a dynamic pivot. I prefer a dynamic crosstab as I find the syntax less obtuse and it has a slight benefit from a performance standpoint too. :)
Here is an article which explains this methodology very well. http://www.sqlservercentral.com/articles/Crosstab/65048/
Also, I am using the DelimitedSplit8K function originally penned by Jeff Moden and improved over time through the community. You can read about it and find the code for it here. http://www.sqlservercentral.com/articles/Tally+Table/72993/
if OBJECT_ID('tempdb..#Something') is not null
drop table #Something;
create table #something
(
Column1 varchar(5)
, Column2 varchar(5)
, Column3 varchar(50)
);
insert #something
select 'ABC', '123', 'User7;User9' union all
select 'nbm', 'qre', 'User1;User2;User3' union all
select 'POI', 'kjh', 'User1;User4;User5;User9';
declare #StaticPortion nvarchar(2000) = 'with orderedResults as
(
select s.Column1
, s.Column2
, x.Item
, x.ItemNumber
from #something s
cross apply dbo.DelimitedSplit8K(Column3, '';'') x
)
select Column1
, Column2
';
declare #DynamicPortion nvarchar(max) = '';
WITH
E1(N) AS (select 1 from (values (1),(1),(1),(1),(1),(1),(1),(1),(1),(1))dt(n)),
E2(N) AS (SELECT 1 FROM E1 a, E1 b), --10E+2 or 100 rows
E4(N) AS (SELECT 1 FROM E2 a, E2 b), --10E+4 or 10,000 rows max
cteTally(N) AS
(
SELECT ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) FROM E4
)
select #DynamicPortion = #DynamicPortion + ', MAX(Case when ItemNumber = ' + CAST(N as varchar(6)) + ' then Item end) as Subject' + CAST(N as varchar(6)) + CHAR(10)
from cteTally t
where t.N <=
(
select top 1 COUNT(*)
from #something s
cross apply dbo.DelimitedSplit8K(Column3, ';') x
group by Column1
Order by COUNT(*) desc
);
declare #FinalStaticPortion nvarchar(2000) = ' from orderedResults group by Column1, Column2 order by Column1, Column2';
declare #SqlToExecute nvarchar(max) = #StaticPortion + #DynamicPortion + #FinalStaticPortion;
select #SqlToExecute;
--uncomment the following line when you are sure this is what you want to execute.
--exec sp_executesql #SqlToExecute;
For MySQl below code can be used. This is just a sample code
#num_Column3 := 1 + LENGTH(#Column3) - LENGTH(REPLACE(#Column3, '|', '')) AS num_Column3
,IF(#num_Column3 > 0, SUBSTRING_INDEX(SUBSTRING_INDEX(#Column3)), '|', 1), '|', -1), '') AS RC_user
Currently building a SELECT statement in SQL Server 2008 but would like to make this SELECT statement dynamic, so the columns can be defined based on values in a table. I heard about pivot table and cursors, but seems kind of hard to understand at my current level, here is the code;
DECLARE #date DATE = null
IF #date is null
set # date = GETDATE() as DATE
SELECT
Name,
value1,
value2,
value3,
value4
FROM ref_Table a
FULL OUTER JOIN (
SELECT
PK_ID ID,
sum(case when FK_ContainerType_ID = 1 then 1 else null) Box,
sum(case when FK_ContainerType_ID = 2 then 1 else null) Pallet,
sum(case when FK_ContainerType_ID = 3 then 1 else null) Bag,
sum(case when FK_ContainerType_ID = 4 then 1 else null) Drum
from
Packages
WHERE
#date between PackageStart AND PackageEnd
group by PK_ID ) b on a.Name = b.ID
where
Group = 0
The following works great for me , but PK_Type_ID and the name of the column(PackageNameX,..) are hard coded, I need to be dynamic and it can build itself based on present or futures values in the Package table.
Any help or guidance on the right direction would be greatly appreciated...,
As requested
ref_Table (PK_ID, Name)
1, John
2, Mary
3, Albert
4, Jane
Packages (PK_ID, FK_ref_Table_ID, FK_ContainerType_ID, PackageStartDate, PackageEndDate)
1 , 1, 4, 1JAN2014, 30JAN2014
2 , 2, 3, 1JAN2014, 30JAN2014
3 , 3, 2, 1JAN2014, 30JAN2014
4 , 4, 1, 1JAN2014, 30JAN2014
ContainerType (PK_ID, Type)
1, Box
2, Pallet
3, Bag
4, Drum
and the result should look like this;
Name Box Pallet Bag Drum
---------------------------------------
John 1
Mary 1
Albert 1
Jane 1
The following code like I said works great, the issue is the Container table is going to grow and I need to replicated the same report without hard coding the columns.
What you need to build is called a dynamic pivot. There are plenty of good references on Stack if you search out that term.
Here is a solution to your scenario:
IF OBJECT_ID('tempdb..##ref_Table') IS NOT NULL
DROP TABLE ##ref_Table
IF OBJECT_ID('tempdb..##Packages') IS NOT NULL
DROP TABLE ##Packages
IF OBJECT_ID('tempdb..##ContainerType') IS NOT NULL
DROP TABLE ##ContainerType
SET NOCOUNT ON
CREATE TABLE ##ref_Table (PK_ID INT, NAME NVARCHAR(50))
CREATE TABLE ##Packages (PK_ID INT, FK_ref_Table_ID INT, FK_ContainerType_ID INT, PackageStartDate DATE, PackageEndDate DATE)
CREATE TABLE ##ContainerType (PK_ID INT, [Type] NVARCHAR(50))
INSERT INTO ##ref_Table (PK_ID,NAME)
SELECT 1,'John' UNION
SELECT 2,'Mary' UNION
SELECT 3,'Albert' UNION
SELECT 4,'Jane'
INSERT INTO ##Packages (PK_ID, FK_ref_Table_ID, FK_ContainerType_ID, PackageStartDate, PackageEndDate)
SELECT 1,1,4,'2014-01-01','2014-01-30' UNION
SELECT 2,2,3,'2014-01-01','2014-01-30' UNION
SELECT 3,3,2,'2014-01-01','2014-01-30' UNION
SELECT 4,4,1,'2014-01-01','2014-01-30'
INSERT INTO ##ContainerType (PK_ID, [Type])
SELECT 1,'Box' UNION
SELECT 2,'Pallet' UNION
SELECT 3,'Bag' UNION
SELECT 4,'Drum'
DECLARE #DATE DATE, #PARAMDEF NVARCHAR(MAX), #COLS NVARCHAR(MAX), #SQL NVARCHAR(MAX)
SET #DATE = '2014-01-15'
SET #COLS = STUFF((SELECT DISTINCT ',' + QUOTENAME(T.[Type])
FROM ##ContainerType T
FOR XML PATH, TYPE).value('.', 'NVARCHAR(MAX)'),1,1,'')
SET #SQL = 'SELECT [Name], ' + #COLS + '
FROM (SELECT [Name], [Type], 1 AS Value
FROM ##ref_Table R
JOIN ##Packages P ON R.PK_ID = P.FK_ref_Table_ID
JOIN ##ContainerType T ON P.FK_ContainerType_ID = T.PK_ID
WHERE #DATE BETWEEN P.PackageStartDate AND P.PackageEndDate) X
PIVOT (COUNT(Value) FOR [Type] IN (' + #COLS + ')) P
'
PRINT #COLS
PRINT #SQL
SET #PARAMDEF = '#DATE DATE'
EXEC SP_EXECUTESQL #SQL, #PARAMDEF, #DATE=#DATE
Output:
Name Bag Box Drum Pallet
Albert 0 0 0 1
Jane 0 1 0 0
John 0 0 1 0
Mary 1 0 0 0
Static Query:
SELECT [Name],[Box],[Pallet],[Bag],[Drum] FROM
(
SELECT *
FROM
(
SELECT rf.Name,cnt.[Type], pk.PK_ID AS PKID, rf.PK_ID AS RFID
FROM ref_Table rf INNER JOIN Packages pk ON rf.PK_ID = pk.FK_ref_Table_ID
INNER JOIN ContanerType cnt ON cnt.PK_ID = pk.FK_ContainerType_ID
) AS SourceTable
PIVOT
(
COUNT(PKID )
FOR [Type]
IN ( [Box],[Pallet],[Bag],[Drum])
) AS PivotTable
) AS Main
ORDER BY RFID
Dynamic Query:
DECLARE #columnList nvarchar (MAX)
DECLARE #pivotsql nvarchar (MAX)
SELECT #columnList = STUFF(
(
SELECT ',' + '[' + [Type] + ']'
FROM ContanerType
FOR XML PATH( '')
)
,1, 1,'' )
SET #pivotsql =
N'SELECT [Name],' + #columnList + ' FROM
(
SELECT *
FROM
(
SELECT rf.Name,cnt.[Type], pk.PK_ID AS PKID, rf.PK_ID AS RFID
FROM ref_Table rf INNER JOIN Packages pk ON rf.PK_ID = pk.FK_ref_Table_ID
INNER JOIN ContanerType cnt ON cnt.PK_ID = pk.FK_ContainerType_ID
) AS SourceTable
PIVOT
(
COUNT(PKID )
FOR [Type]
IN ( ' + #columnList + ')
) AS PivotTable
) AS Main
ORDER BY RFID;'
EXEC sp_executesql #pivotsql
Following my tutorial below will help you to understand the PIVOT functionality:
We write sql queries in order to get different result sets like full, partial, calculated, grouped, sorted etc from the database tables. However sometimes we have requirements that we have to rotate our tables. Sounds confusing?
Let's keep it simple and consider the following two screen grabs.
SQL Table:
Expected Results:
Wow, that's look like a lot of work! That is a combination of tricky sql, temporary tables, loops, aggregation......, blah blah blah
Don't worry let's keep it simple, stupid(KISS).
MS SQL Server 2005 and above has a function called PIVOT. It s very simple to use and powerful. With the help of this function we will be able to rotate sql tables and result sets.
Simple steps to make it happen:
Identify all the columns those will be part of the desired result set.
Find the column on which we will apply aggregation(sum,ave,max,min etc)
Identify the column which values will be the column header.
Specify the column values mentioned in step3 with comma separated and surrounded by square brackets.
So, if we now follow above four steps and extract information from the above sales table, it will be as below:
Year, Month, SalesAmount
SalesAmount
Month
[Jan],[Feb] ,[Mar] .... etc
We are nearly there if all the above steps made sense to you so far.
Now we have all the information we need. All we have to do now is to fill the below template with required information.
Template:
Our SQL query should look like below:
SELECT *
FROM
(
SELECT SalesYear, SalesMonth,Amount
FROM Sales
) AS SourceTable
PIVOT
(
SUM(Amount )
FOR SalesMonth
IN ( [Jan],[Feb] ,[Mar],
[Apr],[May],[Jun] ,[Jul],
[Aug],[Sep] ,[Oct],[Nov] ,[Dec])
) AS PivotTable;
In the above query we have hard coded the column names. Well it's not fun when you have to specify a number of columns.
However, there is a work arround as follows:
DECLARE #columnList nvarchar (MAX)
DECLARE #pivotsql nvarchar (MAX)
SELECT #columnList = STUFF(
(
SELECT ',' + '[' + SalesMonth + ']'
FROM Sales
GROUP BY SalesMonth
FOR XML PATH( '')
)
,1, 1,'' )
SET #pivotsql =
N'SELECT *
FROM
(
SELECT SalesYear, SalesMonth,Amount
FROM Sales
) AS SourceTable
PIVOT
(
SUM(Amount )
FOR SalesMonth
IN ( ' + #columnList +' )
) AS PivotTable;'
EXEC sp_executesql #pivotsql
Hopefully this tutorial will be a help to someone somewhere.
Enjoy coding.
I need a query that will return a table where each column is the count of distinct values in the columns of another table.
I know how to count the distinct values in one column:
select count(distinct columnA) from table1;
I suppose that I could just make this a really long select clause:
select count(distinct columnA), count(distinct columnB), ... from table1;
but that isn't very elegant and it's hardcoded. I'd prefer something more flexible.
This code should give you all the columns in 'table1' with the respective distinct value count for each one as data.
DECLARE #TableName VarChar (Max) = 'table1'
DECLARE #SqlString VarChar (Max)
set #SqlString = (
SELECT DISTINCT
'SELECT ' +
RIGHT (ColumnList, LEN (ColumnList)-1) +
' FROM ' + Table_Name
FROM INFORMATION_SCHEMA.COLUMNS COL1
CROSS AppLy (
SELECT ', COUNT (DISTINCT [' + COLUMN_NAME + ']) AS ' + '''' + COLUMN_NAME + ''''
FROM INFORMATION_SCHEMA.COLUMNS COL2
WHERE COL1.TABLE_NAME = COL2.TABLE_NAME
FOR XML PATH ('')
) TableColumns (ColumnList)
WHERE
1=1 AND
COL1.TABLE_NAME = #TableName
)
EXECUTE (#SqlString)
try this (sql server 2005 syntax):
DECLARE #YourTable table (col1 varchar(5)
,col2 int
,col3 datetime
,col4 char(3)
)
insert into #YourTable values ('abcdf',123,'1/1/2009','aaa')
insert into #YourTable values ('aaaaa',456,'1/2/2009','bbb')
insert into #YourTable values ('bbbbb',789,'1/3/2009','aaa')
insert into #YourTable values ('ccccc',789,'1/4/2009','bbb')
insert into #YourTable values ('aaaaa',789,'1/5/2009','aaa')
insert into #YourTable values ('abcdf',789,'1/6/2009','aaa')
;with RankedYourTable AS
(
SELECT
ROW_NUMBER() OVER(PARTITION by col1 order by col1) AS col1Rank
,ROW_NUMBER() OVER(PARTITION by col2 order by col2) AS col2Rank
,ROW_NUMBER() OVER(PARTITION by col3 order by col3) AS col3Rank
,ROW_NUMBER() OVER(PARTITION by col4 order by col4) AS col4Rank
FROM #YourTable
)
SELECT
SUM(CASE WHEN col1Rank=1 THEN 1 ELSE 0 END) AS col1DistinctCount
,SUM(CASE WHEN col2Rank=1 THEN 1 ELSE 0 END) AS col2DistinctCount
,SUM(CASE WHEN col3Rank=1 THEN 1 ELSE 0 END) AS col3DistinctCount
,SUM(CASE WHEN col4Rank=1 THEN 1 ELSE 0 END) AS col4DistinctCount
FROM RankedYourTable
OUTPUT:
col1DistinctCount col2DistinctCount col3DistinctCount col4DistinctCount
----------------- ----------------- ----------------- -----------------
4 3 6 2
(1 row(s) affected)
and it's hardcoded.
It is not hardcoding to provide a field list for a sql statement. It's common and acceptable practice.
This won't necessarily be possible for every field in a table. For example, you can't do a DISTINCT against a SQL Server ntext or image field unless you cast them to other data types and lose some precision.
I appreciate all of the responses. I think the solution that will work best for me in this situation (counting the number of distinct values in each column of a table from an external program that has no knowledge of the table except its name) is as follows:
Run "describe table1" and pull out the column names from the result.
Loop through the column names and create the query to count the distinct values in each column. The query will look something like "select count(distinct columnA), count(distinct columnB), ... from table1".
Raj More's answer works well if you don't need to consider null as a value as count(distinct...) does not count null.
Here is a modification to count values including null by converting values to a string and replacing null with "NULL AS SOME IMPOSSIBLE STRING":
DECLARE #TableName VarChar (1024) = 'tableName'
DECLARE #SqlString VarChar (Max)
set #SqlString = (
SELECT DISTINCT
'SELECT ' +
RIGHT (ColumnList, LEN (ColumnList)-1) +
' FROM ' + Table_Name
FROM INFORMATION_SCHEMA.COLUMNS COL1
CROSS AppLy (
SELECT ', COUNT (DISTINCT coalesce(cast([' + COLUMN_NAME + '] as varchar),
''NULL AS SOME IMPOSSIBLE STRING'')) AS ' + '''' + COLUMN_NAME + ''''
FROM INFORMATION_SCHEMA.COLUMNS COL2
WHERE COL1.TABLE_NAME = COL2.TABLE_NAME
FOR XML PATH ('')
) TableColumns (ColumnList)
WHERE
COL1.TABLE_NAME = #TableName
)
EXECUTE (#SqlString)
DISTINCT is evil. Do COUNT/GROUP BY