Sequential Column names - sql-server

Having a simple query such as:
select * from foo
Where the output has the columns
bar | abc | def
---------------
...............
It is possible to encapsulate this query into another one and give sequential names instead to the columns such as 1|2|3... (mantaining all the rows intact)?
I know this sounds weird and probably it isn't even possible.
Thanks for the help!

Try This
DECLARE #Sql NVARCHAR(max),
#TableName VARCHAR(100) = '<YourTableName>'
;WITH CTE
AS
(
SELECT DENSE_RANK()OVER (ORDER BY COLUMN_NAME) Rno,
TABLE_NAME,
COLUMN_NAME
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_CATALOG='Database'
AND TABLE_NAME = #TableName
)
SELECT 'SELECT '+ STUFF((SELECT ', '+ COLUMN_NAME +' AS '+ QUOTENAME(CAST(Rno AS VARCHAR))
FROM CTE
FOR XML PATH ('')),1,1,'') + ' FROM '+#TableName
PRINT #Sql
EXEC (#Sql)

Try this:
DECLARE #TableName NVARCHAR(100) = 'YOUR TABLENAME HERE',
#Query NVARCHAR(MAX) = 'SELECT '
SELECT #Query = CONCAT(#Query, ' ', COLUMN_NAME, ' AS ', QUOTENAME(ROW_NUMBER() OVER(ORDER BY ORDINAL_POSITION)), ',
')
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = #TableName
SET #Query = SUBSTRING(#Query, 0, LEN(#Query) - 3) + '
FROM ' + QUOTENAME(#TableName)
You use INFORMATION_SCHEMA.COLUMNS to get all our table's columns,
ROW_NUMBER() window function to generate sequential number for column aliases and sp_ExecuteSQL to execute dynamic generated queries.

Related

Unpivot all other columns

Im new to Stack overflow and SQL and I'm trying to replicate a function in Microsoft Power Query to use in SQL instead.
I know how to Unpivot and keep 1 Column in SQL and then had to reference all the other columns by name to make the unpivot.
Now I need to Keep 3 ID columns and Unpivot the rest of the columns
(This table has 355 columns right now and will change)
Can anyone help me with this?
This is the furthest I got (Thanks to RAV DBLearning on Youtube), but I cant seem to find a way to Convert the columns types to 1 type.
DECLARE
#SQLSTRING NVARCHAR(MAX),
#COLUMNLIST NVARCHAR(1000) = ''
SELECT
#COLUMNLIST = #COLUMNLIST + QUOTENAME(NAME) + ','
FROM
sys.columns
WHERE
OBJECT_ID = OBJECT_ID('xp.XPROPERTYVALUES') AND
--COLUMN_ID NOT IN(1,2,3)
COLUMN_ID IN(452,453,454)
SELECT
#COLUMNLIST = LEFT(#COLUMNLIST,LEN(#COLUMNLIST)-1)
SET
#SQLSTRING =
'
SELECT
upv.id,
upv.item_id,
upv.itemtype_id,
upv.X_Category,
upv.X_Values
FROM
xp.XPROPERTYVALUES
UNPIVOT
(
X_Values FOR X_Category
IN
(' + #COLUMNLIST + ')
) AS upv
'
PRINT
(#SQLSTRING)
EXECUTE
sp_executesql #SQLSTRING
It just needs a source query.
And you can re-use the calculated column list for that.
DECLARE #SQLSTRING NVARCHAR(MAX),
#COLUMNLIST NVARCHAR(MAX);
DECLARE #TABLENAME VARCHAR(30) = 'xp.XPROPERTYVALUES';
SELECT #COLUMNLIST = CONCAT(#COLUMNLIST + ', ', QUOTENAME(NAME))
FROM sys.columns
WHERE OBJECT_ID = OBJECT_ID(#TABLENAME)
AND LOWER(NAME) NOT LIKE '%id';
SET #SQLSTRING = N'SELECT upv.id
, upv.item_id, upv.itemtype_id
, upv.X_Category, upv.X_Values
FROM
(
SELECT id, item_id, itemtype_id,
'+ #COLUMNLIST + N'
FROM '+ #TABLENAME +N'
) src
UNPIVOT
(
X_Values FOR X_Category IN (' + #COLUMNLIST + N')
) upv';
-- SELECT #SQLSTRING;
EXECUTE sp_executesql #SQLSTRING;
db<>fiddle here

How to get distinct count of values of all the columns of a table based on where condition in sql server?

I have a table with records which has 100 columns, I need to get the count of distinct values of all the columns from this table based on some condition (where clause).
Below query is working fine, but I'm not able to use the where clause. So it's giving the result for all the records of the table. But I want it to be based on some condition lets say column file_id = 1;. My question is how to use where clause with the below query. Or if there is any other alternative way to solve this problem.
declare #SQL nvarchar(max)
set #SQL = ''
;with cols as (
select Table_Schema, Table_Name, Column_Name, Row_Number() over(partition by Table_Schema, Table_Name
order by ORDINAL_POSITION) as RowNum
from INFORMATION_SCHEMA.COLUMNS
)
select #SQL = #SQL + case when RowNum = 1 then '' else ' union all ' end
+ ' select ''' + Column_Name + ''' as Column_Name, count(distinct ' + quotename (Column_Name) + ' ) As DistinctCountValue,
count( '+ quotename (Column_Name) + ') as CountValue FROM ' + quotename (Table_Schema) + '.' + quotename (Table_Name)
from cols
where Table_Name = 'table_name' --print #SQL
execute (#SQL)
I am using the dynamic query because I need to reuse this query for other tables also.
First get the columns and use stuff to generate the select in this way:
SELECT COUNT(ColumnA) AS ColumnA, COUNT(ColumnB AS ColumnB), COUNT(ColumnC) AS ColumnC....
That way you only select on your table once to get all counts, After that, use CROSS APPLY to "unpivot" those columns and return the output on one row per column
CROSS APPLY(
VALUES(1, 'ColumnA', ColumnA), (2, 'ColumnB', ColumnB), (3, 'ColumnC', ColumnC)
)(ID, ColumnName, DistinctCountValue)
For the filter, use sp_executesql and send the file_id as parameter
exec SP_executesql #SQL, N'#FID INT', #FID = #FileID
Since you are using all columns of the table Row_Number() over(partition by Table_Schema, Table_Name order by ORDINAL_POSITION) as RowNum becomes redundant, ORDINAL_POSITION already has the value that you are looking for
declare #tablename nvarchar(50) = 'MyTestTable'
declare #fileID int = 1
declare #SQL nvarchar(max)
set #SQL = ''
;with cols as (
select TABLE_SCHEMA, TABLE_NAME, COLUMN_NAME, ORDINAL_POSITION
from INFORMATION_SCHEMA.COLUMNS
where TABLE_NAME = #TableName
)
select #SQL = ';WITH CTE AS (SELECT
' +
STUFF((
SELECT ', COUNT(DISTINCT ' + QUOTENAME(COLUMN_NAME) + ') AS ' + QUOTENAME(COLUMN_NAME)
FROM cols
ORDER BY ORDINAL_POSITION
FOR XML PATH('')
), 1, 1, '')
+ '
FROM ' + #TableName + '
WHERE File_ID = #FID
)
SELECT B.*
FROM CTE
CROSS APPLY (
VALUES ' +STUFF((
SELECT ',( ' + CAST(ORDINAL_POSITION AS VARCHAR) + ',' + QUOTENAME(COLUMN_NAME,'''') + ',' + QUOTENAME(COLUMN_NAME) + ')'
FROM cols
ORDER BY ORDINAL_POSITION
FOR XML PATH('')
), 1, 1, '') + '
)B (ID,ColumnName,DistinctCountValue)
'
from cols
exec SP_executesql #SQL, N'#FID INT', #FID = #FileID
The query below creates a table of all the column names and uses a while loop to select the count for whatever WHERE clause you want to use. This should be pretty flexible for any table; just update the top variables. Note that this will not count a column where its value is null. You can add a case to the #Query parameter if that's what you want. Since it processes each row individually, I added in a temp table so you only hit the db once.
IF OBJECT_ID('tempdb..##SourceValues') IS NOT NULL
DROP TABLE ##SourceValues
DECLARE #Schema VARCHAR(50) = 'SomeSchema'
DECLARE #Table VARCHAR(50) = 'SomeTable'
DECLARE #WhereClause VARCHAR(MAX) = ' Some WHERE clause'
DECLARE #ColumnName VARCHAR(50)
DECLARE #ProcessedRows TABLE(ColumnName VARCHAR(50), DistinctCount INT)
DECLARE #Columns TABLE(RowNumber INT, ColumnName VARCHAR(100))
INSERT INTO #Columns SELECT ROW_NUMBER() OVER(ORDER BY COLUMN_NAME DESC), COLUMN_NAME FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME = #Table
DECLARE #Count INT = (SELECT MAX(RowNumber) FROM #Columns)
DECLARE #Counter INT = 0
DECLARE #DistinctCount INT
DECLARE #Query NVARCHAR(MAX)
EXEC('SELECT * INTO ##SourceValues FROM ' + #Table +' (NOLOCK)')
WHILE #Counter < #Count
BEGIN
SET #Counter += 1
SET #ColumnName = (SELECT ColumnName FROM #Columns WHERE RowNumber = #Counter)
SET #Query = 'SELECT #OutPut = COUNT(' + #ColumnName + ') FROM ' + #Schema + '.' + ' ##SourceValues ' + #WhereClause
EXECUTE sp_executesql #Query, N'#Output INT OUT', #DistinctCount OUT
INSERT INTO #ProcessedRows(ColumnName, DistinctCount) VALUES (#ColumnName, #DistinctCount)
END
SELECT * FROM #ProcessedRows
Let's try some different approach.
Get all values unpivoted as Param/Value:
1) Collect list of tables and columns to be used in dynamic SQL:
DROP TABLE IF EXISTS #Base;
;WITH SchemaData AS (
SELECT t.name AS [TableName],c.name AS [ColumnName],c.column_id AS [ColumnOrderID]
FROM sys.tables t
INNER JOIN sys.columns c ON c.object_id = t.object_id
)
SELECT t.TableName
,STUFF((SELECT ',CONVERT(NVARCHAR(MAX),' + QUOTENAME([ColumnName]) + ') AS ' + QUOTENAME([ColumnName])
FROM SchemaData a WHERE (a.TableName = t.TableName) FOR XML PATH(''),TYPE).value('(./text())[1]','NVARCHAR(MAX)'),1,1,'') AS [SelectClause]
,STUFF((SELECT ',' + QUOTENAME([ColumnName]) FROM SchemaData a WHERE (a.TableName = t.TableName) FOR XML PATH(''),TYPE).value('(./text())[1]','NVARCHAR(MAX)'),1,1,'') AS [UnpivotClause]
INTO #Base
FROM SchemaData t
GROUP BY t.TableName
;
2) Get all data inside a temp table
DROP TABLE IF EXISTS #Result;
CREATE TABLE #Result(TableName NVARCHAR(255),ColumnName NVARCHAR(255),[Value] NVARCHAR(MAX));
DECLARE #TableName NVARCHAR(255),#SelectClause NVARCHAR(MAX),#UnpivotClause NVARCHAR(MAX);
DECLARE crPopulateResult CURSOR LOCAL FAST_FORWARD READ_ONLY FOR SELECT b.TableName,b.SelectClause,b.UnpivotClause FROM #Base b;
OPEN crPopulateResult;
FETCH NEXT FROM crPopulateResult INTO #TableName,#SelectClause,#UnpivotClause;
DECLARE #dSql NVARCHAR(MAX);
WHILE ##FETCH_STATUS = 0
BEGIN
SELECT #dSql = N' INSERT INTO #Result(TableName,[ColumnName],[Value])
SELECT up.TableName,up.Param AS [ColumnName],up.[Value]
FROM (
SELECT ''' + #TableName + N''' AS [TableName]
,' + #SelectClause + N'
FROM ' + QUOTENAME(#TableName) + N'
) a
UNPIVOT(Value FOR Param IN (' + #UnpivotClause + N')) up
';
EXEC sp_executesql #stmt = #dSql;
FETCH NEXT FROM crPopulateResult INTO #TableName,#SelectClause,#UnpivotClause;
END
CLOSE crPopulateResult;
DEALLOCATE crPopulateResult;
3) Any filters can be applied with #Results, including Table names, column names, data filters, etc:
SELECT r.TableName,r.ColumnName,COUNT(*) AS [CountValue],COUNT(DISTINCT r.[Value]) AS [DistinctCountValue]
FROM #Result r
--
--WHERE r.ColumnName = 'file_id' AND r.[Value] = '1'
--
GROUP BY r.TableName,r.ColumnName
ORDER BY r.TableName,r.ColumnName
;
To use this with a where clause with this query you just have to put the where clause in the construction after the table name so if you wanted to filter on file_id='1' then you would have:
FROM ' + quotename (Table_Schema) + '.' + quotename (Table_Name) +'where file_id =''1'' '
You can add a #where variable and concatenate that with your big union construction (as part of your select ... from cols). For example:
declare #SQL nvarchar(max)
declare #where nvarchar(max) = ' where file_id = 1'
set #SQL = ''
;with cols as (
select Table_Schema, Table_Name, Column_Name, Row_Number() over(partition by Table_Schema, Table_Name
order by ORDINAL_POSITION) as RowNum
from INFORMATION_SCHEMA.COLUMNS
)
select #SQL = #SQL + case when RowNum = 1 then '' else ' union all ' end
+ ' select ''' + Column_Name + ''' as Column_Name, count(distinct ' + quotename (Column_Name) + ' ) As DistinctCountValue,
count( '+ quotename (Column_Name) + ') as CountValue FROM ' + quotename (Table_Schema) + '.' + quotename (Table_Name)
+ #where
from cols
where Table_Name = 'table_name' --print #SQL
execute (#SQL)
Note that you'll need to escape single quotes in #where if you're searching for a string. For example, declare #where nvarchar(max) = ' where state = ''CT'''.

T-SQL : Script to create view with columns from a select statement

I have some bulk views to create for an entire database.
To create a view the general syntax is as follows:
CREATE VIEW [TABLE_NAME]
AS
SELECT [COLUMN1], [COLUMN2], [COLUMN3], [COLUMN4]
FROM [TABLE_NAME]
WITH CHECK OPTION;
I would like to set the column names in the script above by querying the column names ([COLULMN1], [COLUMN2], etc) from INFORMATION_SCHEMA.COLUMNS.
Is there a way to achieve this by table name?
COALESCE is your friend good programmer. What you want to do is get a csv list of COLUMNS. Then using dynamic sql you can auto generate the rest of the code.
declare #columns AS VARCHAR(MAX)
SELECT #COLUMNS = NULL
select #COLUMNS = coalesce(#columns+',','')+c.name from syscolumns as c
inner join sysobjects as o on c.id = o.id
WHERE O.NAME = 'change me to your table name'
SELECT #COLUMNS
SELECT ' CREATE VIEW ' + 'COOL VIEW NAME' + ' AS ' +
' SELECT ' + #COLUMNS +
' FROM '+ ' change me to your table name '+
' WITH CHECK OPTION;'
EDIT
I purposely didn't declare the view anywhere. If you want to declare the view just execute the scripts like so. BUT YOU SHOULD NEVER just execute code on your servers without reading it all I purposely excluded the execution part as I think it is bad judgement just to cut and paste code and execute it without understanding/testing.
DECLARE #sql varchar(max)
SELECT #sql = ' CREATE VIEW ' + 'COOL VIEW NAME' + ' AS ' +
' SELECT ' + #COLUMNS +
' FROM '+ ' change me to your table name '+
' WITH CHECK OPTION;'
EXEC(#sql);
Here's one option... replace "MyTableName" with the table name you want, or wrap it in a cursor that reads TABLE_NAME from INFORMATION_SCHEMA.VIEWS into #tableName:
DECLARE #tableName sysname;
DECLARE #sql nvarchar(max);
DECLARE #columnList nvarchar(max);
SELECT #tableName = 'MyTableName';
SELECT #columnList = '';
SELECT #columnList += CASE WHEN LEN(#columnList) = 0 THEN '' ELSE ', ' END + COLUMN_NAME
FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME = #tableName ORDER BY ORDINAL_POSITION;
SELECT #sql = 'CREATE VIEW [TABLE_NAME] AS
SELECT ' + #columnList + '
FROM [' + #tableName + ']
WITH CHECK OPTION;'
PRINT #sql
EXEC(#sql);

Select any column with respect to cell containing

I have a table named a. Some cells containing a string 'Empty' in many columns. I want to find this columns. Can you help me?.
Try this dynamic query, it will check all the columns with character data and list the columns which has the word 'Empty'.
DECLARE #SearchText VARCHAR(50) = 'Empty'
DECLARE #sql NVARCHAR(MAX) = 'SELECT '
SELECT #sql = #sql + 'MAX(CASE WHEN ' + c.COLUMN_NAME + ' LIKE ''%'+ #SearchText +'%'' THEN ''' + c.COLUMN_NAME +''' ELSE '''' END) + '','' + '
FROM INFORMATION_SCHEMA.COLUMNS c WHERE c.TABLE_SCHEMA = 'dbo' and c.TABLE_NAME = 'a'
AND c.DATA_TYPE IN ('varchar','char','nvarchar','nchar','sysname')
SET #sql = #sql + ''''' FROM dbo.a'
EXEC sys.sp_executesql #sql
Hope this helps
Use the LIKE operator:
SELECT a.*
FROM a
WHERE a.col1 LIKE '%Empty%' OR a.col2 LIKE '%Empty%' OR ...
In sql server you can get object id of table then using that object id you can fetch columns. In that case it will be as below:
Step 1: First get Object Id of table
select * from sys.tables order by name
Step 2: Now get columns of your table and search in it:
select * from a where 'Empty' in (select name from sys.columns where object_id =1977058079)
Note: object_id is what you get fetch in first step for you relevant table
You can do it using unpivot with an help of dynamic query , here i have done below an working sample for you , there might be some modification you might have to do to put the below psedo code with your working .
Sample table structure been used :
create table ColTest
(
name1 varchar(10),
name2 varchar(10),
name3 varchar(10),
name4 varchar(10)
)
insert into ColTest values ('sdas','asdasda','ewrewr','erefds')
insert into ColTest values ('sdas','asdasda','EMPTY','erefds')
insert into ColTest values ('EMPTY','asdasda','ewrewr','erefds')
DECLARE #table_name SYSNAME
SELECT #table_name = 'ColTest'
DECLARE #tmpTable SYSNAME
SELECT #tmpTable = 'ColTest2'
DECLARE #SQL NVARCHAR(MAX)
SELECT #SQL = '
SELECT * into
' + #tmpTable + '
FROM ' + #table_name + '
UNPIVOT (
cell_value FOR column_name IN (
' + STUFF((
SELECT ', [' + c.name + ']'
FROM sys.columns c WITH(NOLOCK)
LEFT JOIN (
SELECT i.[object_id], i.column_id
FROM sys.index_columns i WITH(NOLOCK)
WHERE i.index_id = 1
) i ON c.[object_id] = i.[object_id] AND c.column_id = i.column_id
WHERE c.[object_id] = OBJECT_ID(#table_name)
AND i.[object_id] IS NULL
FOR XML PATH(''), TYPE).value('.', 'NVARCHAR(MAX)'), 1, 2, '') + '
)
) unpiv'
PRINT #SQL
EXEC sys.sp_executesql #SQL
select * from ColTest2 where cell_value = 'EMPTY'
I'd suggest dynamic SQL
--First you set the variable #TableName to your actual table's name.
DECLARE #TableName VARCHAR(100)='a';
--The following statement will create a list of all columns with a data type containing the word "char" (others should not hold the value Empty)
DECLARE #ColList VARCHAR(MAX)=
STUFF(
(
SELECT ' OR ' + COLUMN_NAME + ' LIKE ''%empty%'''
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME=#TableName AND DATA_TYPE LIKE '%char%'
FOR XML PATH('')
),1,4,'');
--This statement builds a command
DECLARE #cmd VARCHAR(MAX)=
(
SELECT 'SELECT * FROM [' + #TableName + '] WHERE ' + #ColList
);
--Here you can see the command
PRINT #cmd;
--And here it is executed
EXEC(#cmd);

How to SELECT * and get all field alphabetical ordered

This could be a strange question.
I have a table with 100+ columns. I would like to SELECT * all columns and get the resulting query with columns ordered alphabetically.
Is it possible in T-SQL?
Thanks
You could build a dynamic SQL statement using the information available in the system catalog view.
The sample code below shows how:
DECLARE #sql AS NVARCHAR(MAX)
DECLARE #cols AS NVARCHAR(MAX)
DECLARE #tbl NVARCHAR(MAX) = N'your_table' -- this is your source table
SELECT #cols= ISNULL(#cols + ',','') + QUOTENAME(c.name)
FROM sys.tables t
join sys.columns c ON c.object_id = t.object_id
WHERE t.name = #tbl
ORDER BY c.name
SET #sql = N'SELECT ' + #cols + ' FROM ' + #tbl
EXEC sp_executesql #sql
DynamicSQL (SQL Server) example:
declare #TABLE varchar(200) set #TABLE='persons'
declare #SQL nvarchar(max)
set #SQL='select '
select #SQL= #SQL + column_name + ','
from information_schema.columns where table_name=#TABLE order by column_name
select #SQL = left(#SQL,len(#SQL)-1) + ' from ' + #TABLE -- trims the trailing comma
--select #SQL -- If you want to see the query
exec sp_executesql #SQL
DECLARE #Table NVARCHAR(MAX)='T'--pass your table name
DECLARE #SQL NVARCHAR(MAX)='SELECT '
SELECT #SQL=#SQL+',' +NAME FROM
(
SELECT TOP 100 QUOTENAME(NAME) AS NAME
FROM sys.columns
WHERE object_id =
(
SELECT OBJECT_ID FROM sys.tables
WHERE NAME =#Table
)
ORDER BY NAME
) AS SS
SELECT #SQL=STUFF(#SQL,8,1,'')+' FROM '+#Table
EXEC sp_executesql #sql

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