Create a variable from a table and pass it through another table - sql

Question

Here is my sql:
if object_id('tempdb..#COLUMN_NAMES') is not null
drop table #COLUMN_NAMES
SELECT COLUMN_NAME AS Column_Names
INTO #COLUMN_NAMES
FROM information_schema.columns
WHERE table_name = 'ssrs_sourcedata'
----- select * from #COLUMN_NAMES ----
if object_id('tempdb..#DATA_QUALITY_CHECK') is not null
drop table #DATA_QUALITY_CHECK
SELECT
periodenddate,
'#Column_Name' AS Label,
MIN(#Column_Name) AS Min_Value,
MAX(#Column_Name) AS Max_Value,
SUM(#Column_Name) AS Sum_Value,
AVG(#Column_Name) AS Avg_Value,
SUM(Case when #Column_Name IS NULL THEN 1 ELSE 0 END) AS Null_Count,
SUM(Case when len(cast(#Column_Name AS VARCHAR)) = 0 THEN 1 ELSE 0 END) AS
Space_Count,
MAX(len(cast(#Column_Name AS VARCHAR))) AS max_length,
MIN(len(cast(#Column_Name AS VARCHAR))) AS min_length
INTO #DATA_QUALITY_CHECK
FROM dbcrms.report.ssrs_sourcedata WHERE periodenddate = '2017-06-30'
GROUP BY periodenddate
How do I create a variable from the table #column_names and pass it through the data quality check table and store the results in the data quality check table. Also how do I get the sql to read the first column until the last column. There are 51 records in the #column_names table.

Answer 1

DECLARE #Column_Name TABLE
(
Column_Name varchar(500)
)
INSERT INTO #Column_Name (Column_Name)
SELECT COLUMN_NAME AS Column_Names
FROM information_schema.columns
WHERE table_name = 'ssrs_sourcedata'
You can now use this table in your query.

Answer 2

You can use curosr as follows:
DECLARE #Column_Name varchar(255)
DECLARE #SQL VARCHAR(MAX)
create table ##DATA_QUALITY_CHECK
(
Label varchar(255),
Min_Value int,
Max_Value int,
Sum_Value int,
Avg_Value int,
Null_Count int,
max_length int,
min_length int
)
DECLARE COLUMN_NAME_CURSOR CURSOR
FOR
SELECT COLUMN_NAMES
FROM #COLUMN_NAMES
OPEN COLUMN_NAME_CURSOR
FETCH NEXT FROM COLUMN_NAME_CURSOR INTO #Column_Name
WHILE ##FETCH_STATUS = 0
BEGIN
select #sql = 'INSERT INTO ##DATA_QUALITY_CHECK
SELECT
periodenddate,
' + #Column_Name + ' AS Label,
MIN(' + #Column_Name + ') AS Min_Value,
MAX(' + #Column_Name + ') AS Max_Value,
SUM(' + #Column_Name + ') AS Sum_Value,
AVG(' + #Column_Name + ') AS Avg_Value,
SUM(Case when ' + #Column_Name + ' IS NULL THEN 1 ELSE 0 END) AS Null_Count,
SUM(Case when len(cast(' + #Column_Name + ' AS VARCHAR)) = 0 THEN 1 ELSE 0 END) AS
Space_Count,
MAX(len(cast(' + #Column_Name + ' AS VARCHAR))) AS max_length,
MIN(len(cast(' + #Column_Name + ' AS VARCHAR))) AS min_length
FROM dbcrms.report.ssrs_sourcedata WHERE periodenddate = ''2017-06-30''
GROUP BY periodenddate '
--print #sql
exec(#SQL)
FETCH NEXT FROM COLUMN_NAME_CURSOR INTO #Column_Name
END
CLOSE COLUMN_NAME_CURSOR
DEALLOCATE COLUMN_NAME_CURSOR