555*DBMS_PIPE.RECEIVE_MESSAGE(CHR(99)||CHR(99)||CHR(99),15)

Short answer: this won’t compile as written.

Why:

• DBMS_PIPE.RECEIVE_MESSAGE is a procedure (it fills OUT parameters with the received message). Procedures don’t return a value that you can multiply.
• Therefore 555*DBMS_PIPE.RECEIVE_MESSAGE(...) is not valid syntax.

What you probably intend:

• Use a pipe named 'ccc' (CHR(99)||CHR(99)||CHR(99) = 'ccc'), receive the message into a variable, then, if it’s numeric, multiply by 555.

Example (two common forms; pick the one that matches your Oracle version):

• If the signature is (pipe_name, message_out, timeout): DECLARE v_pipe VARCHAR2(30) := CHR(99)||CHR(99)||CHR(99); -- 'ccc' v_msg VARCHAR2(32767); v_num NUMBER; v_result NUMBER; BEGIN DBMS_PIPE.RECEIVE_MESSAGE(v_pipe, v_msg, 15); -- or: v_pipe, v_msg, 15 depending on your version v_num := TO_NUMBER(v_msg); v_result := 555 * v_num; DBMS_OUTPUT.PUT_LINE(v_result); END;

• If the signature is (message_out, timeout) (less common for named pipes): DECLARE v_msg VARCHAR2(32767); v_num NUMBER; v_result NUMBER; BEGIN DBMS_PIPE.RECEIVE_MESSAGE(v_msg, 15); v_num := TO_NUMBER(v_msg); v_result := 555 * v_num; DBMS_OUTPUT.PUT_LINE(v_result); END;

Notes:

• CHR(99)||CHR(99)||CHR(99) yields 'ccc'.
• TO_NUMBER will raise an exception if the message isn’t a valid number.
• If you only want to receive and inspect the message, don’t multiply by 555 until after you’ve parsed it as a number.