Need to implement incremental load from S3 to Snowflake only using snowflake objects.
Accessing S3 location thru WINSCP :

CHECKITEMS_1
CHECKITEMS_2
CHECKITEMS_3
Project_1
Project_2
Project_3

1. Created a external table without columns.

2. Created a view to load data based on filename.

3. Created a tracking table to track which files got loaded.

4. Created Stored procedure to load files one by one incrementally.

   CREATE OR REPLACE PROCEDURE DEV_GR_RDH_DB.NPI.LOAD_NPI_DATA()
   RETURNS STRING
   LANGUAGE SQL
   AS
   $$
   DECLARE
   file_name VARCHAR;
   file_count INTEGER;
   BEGIN
   — Process NPICheckItems files
   FOR file_record IN (
   SELECT METADATA$FILENAME AS file_name
   FROM DEV_GR_RDH_DB.EXTERNAL.EXT_NPI_CSV_COMMA
   WHERE METADATA$FILENAME ILIKE ‘CHECKITEMS%.csv’;
   )
   DO
   file_name := file_record.file_name;

       -- Check if the file has already been processed
       SELECT COUNT(*) INTO :file_count
       FROM DEV_GR_RDH_DB.NPI.TRACK_LOADED_FILES
       WHERE file_name = :file_name;
   
       IF file_count = 0 THEN
           -- Merge data into the target table
         MERGE INTO DEV_GR_RDH_DB.NPI.TRG_NPI_CHECKITEMS trg
         USING DEV_GR_RDH_DB.EXTERNAL.VW_LATEST_NPI_CHECKITEMS stg
         ON trg.CHECKITEMID = stg.CHECKITEMID
         WHEN MATCHED THEN
         UPDATE SET
             CHECKITEMCODE = stg.CHECKITEMCODE,
             CHECKITEMNAME = stg.CHECKITEMNAME,
             CHECKITEMDESCRIPTION = stg.CHECKITEMDESCRIPTION,
             CHECKITEMTYPEID = stg.CHECKITEMTYPEID
         WHEN NOT MATCHED THEN
         INSERT (
             CHECKITEMID, CHECKITEMCODE, CHECKITEMNAME, CHECKITEMDESCRIPTION,
             CHECKITEMTYPEID
         ) VALUES (
             stg.CHECKITEMID, stg.CHECKITEMCODE, stg.CHECKITEMNAME, stg.CHECKITEMDESCRIPTION,
             stg.CHECKITEMTYPEID
         );
   
           -- Track the processed file
           INSERT INTO DEV_GR_RDH_DB.NPI.TRACK_LOADED_FILES (file_name, success_flag, records_affected)
           SELECT :file_name, TRUE, COUNT(*)
           FROM DEV_GR_RDH_DB.NPI.VW_NPI_CHECKITEMS
           WHERE file_name = :file_name
           GROUP BY file_name;
           ELSE
           -- File already processed, skip processing
           CONTINUE;
       END IF;
   END FOR;
   
   
   
   RETURN 'Incremental load process completed successfully.';
   

   END;
   $$;

Similarly we need to include code for Project% in the same code.
But S.P is throwing errors.