no outer join has been formed -- outer join operator (+) ignored Explanation: A column was marked with the outer join operator (+) and compared to a simple expression that doesn't contain another table and column reference. Since no outer join has been formed between two tables Oracle Rdb will ignore the outer join notation. User Action: If this Boolean expression appears before other AND comparisions then you should reorder the AND expressions so that comparisions with literal values and other simple expressions appear last.