Inserting and checking data via stored procedure

Question

I am trying to insert new data into a table and at the same time check if any of the data(treatments) is conflicting with each other according to a 'conflict' attribute in one of the tables. I'm not quite sure if my PL/SQL is actually fully correct, but i am currently getting an error when i try to insert new data saying "exact fetch returns more than requested number of rows". I cant quite figure out what this means exactly. My procedure:

CREATE OR REPLACE PROCEDURE FPRESC (
    FP_ID VARCHAR2,
    FTREAT_ID VARCHAR2,
    FCLIENT_ID VARCHAR2,
    FDOC_ID VARCHAR2,
    FP_DATE DATE)
AS
   V_CLIENT_ID PRESCRIPTION.CLIENT_ID%TYPE;
   V_CONFLICT TREATMENTS.CONFLICT%TYPE;
   V_P_DATE PRESCRIPTION.P_DATE%TYPE;
   V_TREAT_ID TREATMENTS.TREAT_ID%TYPE;
BEGIN
    SELECT P.CLIENT_ID, T.CONFLICT, P.P_DATE, T.TREAT_ID
    INTO V_CLIENT_ID, V_CONFLICT, V_P_DATE, V_TREAT_ID
    FROM PRESCRIPTION P, TREATMENTS T
    WHERE P.TREAT_ID=T.TREAT_ID;

    IF FP_DATE = V_P_DATE AND FCLIENT_ID = V_CLIENT_ID AND FTREAT_ID = V_TREAT_ID AND V_CONFLICT != NULL THEN 
         DBMS_OUTPUT.PUT_LINE('CONFLICT');
    ELSE
         INSERT INTO PRESCRIPTION (P_ID, TREAT_ID, CLIENT_ID, DOC_ID, P_DATE)
         VALUES (FP_ID, FTREAT_ID, FCLIENT_ID, FDOC_ID, FP_DATE);
    END IF;
END FPRESC;
/

and here is an example of the data i am inserting:

 EXEC FPRESC ('P00011', 'T016', 'C00017', 'D006', '28-NOV-14');

This example inserts conflicting data, so i can test if the procedure will be able to identify the conflict.

Answer 1

SELECT P.CLIENT_ID, T.CONFLICT, P.P_DATE, T.TREAT_ID
    INTO V_CLIENT_ID, V_CONFLICT, V_P_DATE, V_TREAT_ID
    FROM PRESCRIPTION P, TREATMENTS T
    WHERE P.TREAT_ID=T.TREAT_ID;

This select should fetch only one record for the logic to work, because of the INTO clause.. You're getting the error because your select is fetching more than 1 row. Fix your logic and it should work..

Answer 2

To follow on with @Shankar, what you have will return every row in the tables where a join exists. You need to filter the results down to a specific row. Probably something like this:

CREATE OR REPLACE PROCEDURE FPRESC (
    FP_ID VARCHAR2,
    FTREAT_ID VARCHAR2,
    FCLIENT_ID VARCHAR2,
    FDOC_ID VARCHAR2,
    FP_DATE DATE)
AS
   V_ROWCOUNT NUMBER;
   V_CLIENT_ID PRESCRIPTION.CLIENT_ID%TYPE;
   V_CONFLICT TREATMENTS.CONFLICT%TYPE;
   V_P_DATE PRESCRIPTION.P_DATE%TYPE;
   V_TREAT_ID TREATMENTS.TREAT_ID%TYPE;
BEGIN
    SELECT COUNT(*)
    INTO V_ROWCOUNT
    FROM PRESCRIPTION P, TREATMENTS T
    WHERE P.TREAT_ID=T.TREAT_ID
          AND P.CLIENT_ID = FCLIENT_ID
          AND P.P_DATE = FP_DATE
          AND T.TREAT_ID = FTREAT_ID
          AND V_CONFLICT != NULL;

    IF (V_ROWCOUNT > 0) THEN 
         DBMS_OUTPUT.PUT_LINE('CONFLICT');
    ELSE
         INSERT INTO PRESCRIPTION (P_ID, TREAT_ID, CLIENT_ID, DOC_ID, P_DATE)
         VALUES (FP_ID, FTREAT_ID, FCLIENT_ID, FDOC_ID, FP_DATE);
    END IF;
END FPRESC;