ORA-00904 invalid identifier

1. Cause: The input column name is missing or invalid.

1-1. Specifies a nonexistent column name.

1-2. The column name defined does not match the case.

1-3. Error in how to use single quotes (') and double quotes (").

1-4. Use special characters in column names.

1-5. Use Oracle reserved words for column names.

2. Solution

2-1. Make sure the column exists in the table.

2-2. Column names enclosed in double quotation marks are case sensitive, so check.

2-3. Enclosing a value with a single quotation mark (') is treated as a value, but enclosing the value with a double quotation mark (") will treat it as an object name.

2-4. Make sure that you do not use a number or symbol before the column name, and then fix it.

2-5. Make sure column names do not use reserved words.