Sketch of querying and updating rows in DB2 from an Excel 97-2004 format file.

gistfile1.py

# http://www.reddit.com/r/learnpython/comments/167cay/using_python_with_excel_and_sql/
# pip install xlwt ibm_db
import xlrd
import logging
import ibm_db_dbi


logging.basicConfig(level=logging.DEBUG)


def valid_data(conn, key):
    """Returns True if the database record is good, else False."""
    # This version selects the entire row and checks that no fields are NULL or
    # empty.
    cursor = conn.cursor()
    # You need to edit the SQL for your schema.
    cursor.execute('SELECT * FROM my_table WHERE id = ?', [key])
    db_row = cursor.fetchone()
    return all(db_row)


def update_data(conn, key, values):
    """Updates the database record with the new data."""
    cursor = conn.cursor()
    # You need to edit the SQL for your schema and the spreadsheet data.
    cursor.execute('UPDATE my_table SET my_col = ?, other_col = ? WHERE id = ?',
        [values[1], values[2], key])


def main(filename, dsn, dry_run=False):
    # Open the spreadsheet and connect to the database.
    book = xlrd.open_workbook(filename=filename)
    conn = ibm_db_dbi.connect(dsn)
    
    # Assumes we want the first sheet.
    sheet = book.sheets()[0]
   
    # Assumes the first column contains database row keys.
    for row_number, key in enumerate(sheet.col_values(0)):
        if not valid_data(conn, key):
            logging.warn('Updating record %r with values on row %r', key, row_number)
            row_values = sheet.row_values(row_number)
            logging.info('Values: %r', row_values)
            
            # Don't do UPDATEs on a dry-run.
            if not dry_run:
                update_data(conn, key, row_values)
        else:
            logging.debug('Valid record %r', key)


if __name__ == "__main__":
    import sys
    
    assert len(sys.argv) == 3, "Usage: ./tool.py <excel filename> <database dsn>"
    # When you are happy it does what you want, change dry_run to False.
    main(filename=sys.argv[1], dsn=sys.argv[2], dry_run=True)