How to pass table name and column name dynamic in SQL - sql

Question

I was trying to pass table name and column name dynamic, this is as part of SSIS process I am trying this stored procedure below.
CREATE PROCEDURE [lnd].[Get_ANCNotullColumn]
(#PassedTableName AS NVarchar(255),
#PassedColumnName AS NVARCHAR(100))
AS
BEGIN
DECLARE #ActualTableName AS NVarchar(255)
SELECT #ActualTableName = QUOTENAME( TABLE_NAME )
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_NAME = #PassedTableName
DECLARE #sql AS NVARCHAR(MAX)
SELECT #sql = 'SELECT COUNT(*) FROM ' + #ActualTableName + ';'
DECLARE #final AS NVARCHAR(MAX)
SELECT #final = #sql + 'WHERE ' + #PassedColumnName + ' IS NULL OR ' + #PassedColumnName + '='''
EXEC(#SQL)
END
On executing this, I am NOT getting count as result, instead I am getting execution success.
EXEC [lnd].[Get_ANCNotullColumn] 'lnd.ANC_LND_ItemOverride', 'comments'
I need to get the count as output.
Also my simple direct query is like this
SELECT COUNT(*)
FROM lnd.ANC_LND_ItemOverride
WHERE Comments IS NULL OR Comments = '' -- 3 is the output

Answer 1

I think you may need to modify you value passing and your concatenation values.
from this statement you need to remove the semi colon as it will throw error
SELECT #sql = 'SELECT COUNT(*) FROM ' + #ActualTableName + ';'
While passing blank values you need additional quotes
SELECT #final = #sql + 'WHERE ' + #PassedColumnName + ' IS NULL OR ' + #PassedColumnName + '= '''''
While execution I believe you wanted to execute final instead of SQL
I think below should give your output:
CREATE PROC [lnd].[Get_ANCNotullColumn]( #PassedTableName as NVarchar(255),#PassedColumnName AS
NVARCHAR(100))
AS
BEGIN
DECLARE #ActualTableName AS NVarchar(255)
SELECT #ActualTableName = QUOTENAME( TABLE_NAME )
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_NAME = #PassedTableName
DECLARE #sql AS NVARCHAR(MAX)
SELECT #sql = 'SELECT COUNT(*) FROM ' + #ActualTableName + ' '
DECLARE #final AS NVARCHAR(MAX)
SELECT #final = #sql + 'WHERE ' + #PassedColumnName + ' IS NULL OR ' + #PassedColumnName + '='''''
EXEC(#final)
END