From 90cdaa2a4f930fbdb8af7ade547ee21e65d10559 Mon Sep 17 00:00:00 2001
From: Aadit Agrawal <tech@aaditagrawal.com>
Date: Tue, 11 Feb 2025 16:19:47 +0530
Subject: [PATCH] Update DBMS/SQL/Week6/writeup.md

---
 DBMS/SQL/Week6/writeup.md | 85 ++++++++++++++++++++-------------------
 1 file changed, 43 insertions(+), 42 deletions(-)

diff --git a/DBMS/SQL/Week6/writeup.md b/DBMS/SQL/Week6/writeup.md
index 1739e63..e649a77 100644
--- a/DBMS/SQL/Week6/writeup.md
+++ b/DBMS/SQL/Week6/writeup.md
@@ -55,14 +55,17 @@ PL/SQL procedure successfully completed.
 ### 3. Create a procedure to display accident information which took place in a particular location.
 
 ```SQL
-SQL> create or replace procedure accident_info(location_value in varchar) IS
-  begin
-        for accident_rec in
-       (select * from accident where location = location_value) loop
-            dbms_output.put_line('Report Number: ' || accident_rec.report_number || ', Date: ' || accident_rec.accd_date || ', Location: ' || accident_rec.location);
-       end loop;
-    end;
-    /
+SQL> CREATE OR REPLACE PROCEDURE accident_info(location_value IN VARCHAR2) IS
+BEGIN
+    FOR accident_rec IN
+    (SELECT * FROM accident WHERE LOCATION = location_value) LOOP
+        DBMS_OUTPUT.PUT_LINE('Report Number: ' || accident_rec.REPORT_NUMBER || 
+                             ', Date: ' || TO_CHAR(accident_rec.ACCD_DATE, 'DD-MON-YYYY') || 
+                             ', Location: ' || accident_rec.LOCATION);
+    END LOOP;
+END;
+/
+
 ```
 ```sql
 SQL> execute accident_info('Delhi India');
@@ -74,23 +77,22 @@ PL/SQL procedure successfully completed.
 ### 4. Create a procedure to identify all drivers who have never been involved in any accidents. The procedure should return their driver-id, name, and address.
 
 ```SQL
-SQL> CREATE OR REPLACE PROCEDURE GetDriversWithoutAccidents AS
-    begin
-        for rec in (
-            select p.driver_id#, p.name, p.address
-            from person p
-            left join participated pa on p.driver_id# = pa.driver_id#
-            where pa.report_number is null
-        ) loop
-            dbms_output.put_line('driver id: ' || rec.driver_id# ||
+SQL> 
+CREATE OR REPLACE PROCEDURE GetDriversWithoutAccidents AS
+BEGIN
+    FOR rec IN (
+        SELECT p.driver_id#, p.name, p.address
+        FROM person p
+        LEFT JOIN participated pa ON p.driver_id# = pa.driver_id#
+        WHERE pa.report_number IS NULL
+    ) LOOP
+        DBMS_OUTPUT.PUT_LINE('driver id: ' || rec.driver_id# ||
+                             ', name: ' || rec.name ||
+                             ', address: ' || rec.address);
+    END LOOP;
+END;
+/
 
-                                 ', name: ' || rec.name ||
-                                 ', address: ' || rec.address);
-        end loop;
-    end;
-    /
-
-Procedure created.
 ```
 ```SQL
 SQL> EXEC GetDriversWithoutAccidents;
@@ -102,25 +104,24 @@ PL/SQL procedure successfully completed.
 
 Q5. Write a function that takes a REGNO as input and returns the total number of accidents in which the car was involved
 ```sql
-SQL> create or replace function gettotalaccidentsbyregno(p_regno in varchar2)
-    return number
-    is
-        v_total_accidents number;
-    begin
-        select count(*)
-        into v_total_accidents
-        from participated
-        where regno = p_regno;
-        return v_total_accidents;
-    exception
-        when no_data_found then
-            return 0;
-        when others then
-            raise;
-    end;
-    /
+SQL> 
+CREATE OR REPLACE FUNCTION gettotalaccidentsbyregno(p_regno IN VARCHAR2)
+RETURN NUMBER
+IS
+    v_total_accidents NUMBER := 0; -- Initialize to 0
+BEGIN
+    SELECT COUNT(*)
+    INTO v_total_accidents
+    FROM participated
+    WHERE REGNO = p_regno;
+
+    RETURN v_total_accidents;
+EXCEPTION
+    WHEN OTHERS THEN
+        RETURN 0; -- Return 0 for any error
+END;
+/
 
-Function created.
 ```
 ```SQL
 SQL> SELECT GetTotalAccidentsByRegno('ABCD0001') AS Total_Accidents