This statement contains a use of the SUM or AVG function applied to a column that has a character data type (CHAR or VARCHAR). If you did not intend to take the sum or average of character strings, review the spelling of column names against the table definition. If a character column actually contains numeric values in character form, you can trick the database server (Version 4.0 and later) into performing an automatic conversion. Instead of applying the function to the column name alone, apply it to the expression in parentheses (column+0).