I've just came across following bug in toad for oracle (v13.2.0.258).
originally I experienced it in a complex statement with a complex formula split into multiple lines.
but I've managed to track it down to this simple case.
divider sign on a separate line causes ORA-923
statement must have been misinterpreted by toad since sqlplus doesn't have a problem with such a formula.
please check.
The TOAD edit window is treating a slash on a line by itself as a command to execute the previous text. You get the error because "select 1" is not a valid SQL statement.
I don't know what the fix, if any, is going to be, but this is why it is happening.
yes, if you type the statement directly in sqlplus, it tries to interpret slash and execute statement.
but if you edit statement in external editor, then it execute without any issue.