isnull for dynamically Generated column - sql

Question

I am getting temp table with dynamically generated columns let say it is columns A,B,C,D etc from other source.
Now in my hand I have temp table with column generated. I had to write stored procedure with the use of temp table.
So my stored procedure is like
create proc someproc()
as
begin
Insert into #searchtable
select isnull(#temp.*,0.00)
End
Now #searchresult is table created by me to store temp table columns. The problem arises when I want to check isnull for #tempdb columns. Because from source it comes it may be 3 columns, again next time it may be 4 columns. It changes.
Since it is dynamically generated I cannot use each column name and use like below:
isnull(column1,0.00)
isnull(column2,0.00)
I had to use all column generated and check if value is empty use 0.00
I tried this below but not working:
isnull(##temp.*,0.00),

Answer 1

Try with Dynamic code by fetching the column name for your dynamic table from [database].NFORMATION_SCHEMA.COLUMNS
--Get the Column Names for the your dynamic table and add the ISNULL Check:
DECLARE #COLS VARCHAR(MAX) = ''
SELECT #COLS = #COLS + ', ISNULL(' + COLUMN_NAME + ', 0.00) AS ' + COLUMN_NAME
FROM tempdb.INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME LIKE '#temp[_]%' -- Dynamic Table (here, Temporary table)
DECLARE #COLNAMES VARCHAR(MAX) = STUFF(#COLS, 1, 1, '')
--Build your Insert Command:
DECLARE #cmd VARCHAR(MAX) = '
INSERT INTO #temp1
SELECT ' + #COLNAMES + ' FROM #temp'
--Execute:
EXEC (#cmd)

Answer 2

Hope, I understood your comment right:
CREATE PROCEDURE someproc
AS
IF OBJECT_ID(N'#searchtable') IS NOT NULL DROP TABLE #searchtable
IF OBJECT_ID(N'#temp') IS NOT NULL
BEGIN
DECLARE #sql nvarchar(max),
#cols nvarchar(max)
SELECT #cols = (
SELECT ',COALESCE('+QUOTENAME([name])+',0.00) as '+QUOTENAME([name])
FROM sys.columns
WHERE [object_id] = OBJECT_ID(N'#temp')
FOR XML PATH('')
)
SELECT #sql = N'SELECT '+STUFF(#cols,1,1,'')+' INTO #searchtable FROM #temp'
EXEC sp_executesql #sql
END
This SP checks if #temp table exists. If exists then it takes all column names from sys.columns table and we make a string like ,COALESCE([Column1],0.00) as [Column1], etc. Then we make a dynamic SQL query like:
SELECT COALESCE([Column1],0.00) as [Column1] INTO #searchtable FROM #temp
And execute it. This query result will be stored in #searchtable.
Notes: Use COALESCE instead of ISNULL, and sp_executesql instead of direct exec. It is a good practice.