Added P10 trigger (plsql). Engineered by Macho.

Practical/Practical Exam/PL-SQL/P10 - Trigger.md

@@ -0,0 +1,87 @@
+# P10 - Trigger
+
+**Problem Statement:** Trigger: Write a after trigger for Insert, update and delete event considering following requirement:
+Emp(Emp_no, Emp_name, Emp_salary)
+a) Trigger should be initiated when salary tried to be inserted is less than Rs.50,000/-
+b) Trigger should be initiated when salary tried to be updated for value less than Rs. 50,000/-
+Also the new values expected to be inserted will be stored in new table Tracking(Emp_no,Emp_salary).
+
+---
+
+## Creating tables:
+```sql
+CREATE TABLE Emp(
+    Emp_no NUMBER(14),
+    Emp_name VARCHAR(255),
+    Emp_salary NUMBER(14)
+);
+
+CREATE TABLE Tracking(
+    Emp_no NUMBER(14),
+    Emp_salary NUMBER(14)
+);
+
+```
+
+## Trigger
+```sql
+CREATE OR REPLACE TRIGGER P10
+AFTER INSERT OR UPDATE ON Emp
+FOR EACH ROW
+BEGIN
+	IF inserting THEN
+		IF (:New.Emp_salary < 50000) THEN
+			insert into Tracking (Emp_no, Emp_salary) VALUES (:New.Emp_no, :New.Emp_salary);
+			DBMS_OUTPUT.PUT_LINE('Inserting record with salary < 50000');
+		END IF;
+	ELSIF updating THEN
+		IF (:New.Emp_salary < 50000) THEN
+			UPDATE Tracking SET Emp_salary = :New.Emp_salary WHERE Emp_no = :Old.Emp_no;
+			DBMS_OUTPUT.PUT_LINE('Updated value of salary < 50000 for a record');
+		END IF;
+	END IF;
+END;
+/
+
+```
+
+1. After performing insertion operation:
+```sql
+INSERT INTO Emp VALUES (1, 'Tanmay', 45000);
+INSERT INTO Emp VALUES (2, 'Rajesh', 35000);
+
+```
+
+<details>
+  <summary>Output</summary>
+  1 row(s) inserted.<br>
+  Inserting record with salary < 50000<br>
+<br>
+  1 row(s) inserted.<br>
+  Inserting record with salary < 50000<br>
+<br>
+  Tracking:<br>
+  EMP_NO	EMP_SALARY<br>
+  1	45000<br>
+  2	35000<br>
+
+</details>
+
+2. After performing update operation:
+```sql
+UPDATE Emp SET Emp_salary = 43000 WHERE Emp_no = 1;
+
+```
+<details>
+  <summary>Output</summary>
+  1 row(s) updated.<br>
+  Updated value of salary < 50000 for a record<br>
+  <br>
+  Tracking:<br>
+  EMP_NO	EMP_SALARY<br>
+  1	43000<br>
+  2	35000<br>
+
+</details>
+
+---

Practical/Practical Exam/PL-SQL/P7 - Age_calc.md

@@ -3,34 +3,37 @@
 ## Creating function
 
 ```sql
-CREATE OR REPLACE FUNCTION Age_calc (p_dob IN DATE)
-RETURN VARCHAR IS
--- declare
-  ageOP VARCHAR2(255);
-  years NUMBER;
-  months NUMBER;
-  days NUMBER;
-
+CREATE OR REPLACE FUNCTION P7(
+    dob IN DATE,
+    f_month OUT NUMBER,
+    f_day OUT NUMBER
+)
+RETURN NUMBER
+IS
+	current_date DATE := SYSDATE;
+	year_diff NUMBER;
+	month_diff NUMBER;
+	day_diff NUMBER;
 BEGIN
+	year_diff := EXTRACT(YEAR FROM current_date) - EXTRACT(YEAR FROM dob);
+	month_diff := EXTRACT(MONTH FROM current_date) - EXTRACT(MONTH FROM dob);
+	day_diff := EXTRACT(DAY FROM current_date) - EXTRACT(DAY FROM dob);
 
-  years := EXTRACT(YEAR FROM SYSDATE) - EXTRACT(YEAR FROM p_dob);
-  months := EXTRACT(MONTH FROM SYSDATE) - EXTRACT(MONTH FROM p_dob);
-  days := EXTRACT(DAY FROM SYSDATE) - EXTRACT(DAY FROM p_dob);
+	IF (day_diff < 0) THEN
+		month_diff := month_diff - 1;
+		day_diff := day_diff + EXTRACT(DAY FROM last_day(add_months(SYSDATE, -1)));
+	END IF;
 
-  IF (days < 1) THEN
-    months := months - 1;
-    days := days + EXTRACT(DAY FROM LAST_DAY(ADD_MONTHS(SYSDATE, -1)));
-  END IF;
+	IF (month_diff < 0) THEN
+		year_diff := year_diff - 1;
+		month_diff := month_diff + 12;
+	END IF;
 
-  IF (months < 1) THEN
-    years := years - 1;
-    months := months + 12;
-  END IF;
+	f_month := month_diff;
+	f_day := day_diff;
 
-  ageOP := 'Given person is ' || years || ' years ' || months || ' months ' || days || ' days old.';
-
-RETURN ageOP;
-END Age_calc;
+	RETURN year_diff;
+END;
 /
 
 ```
@@ -38,8 +41,13 @@ END Age_calc;
 ## Calling function
 
 ```sql
+DECLARE
+    years NUMBER;
+    months NUMBER;
+    days NUMBER;
 BEGIN
-  DBMS_OUTPUT.PUT_LINE(Age_calc(TO_DATE('2004-04-28', 'YYYY-MM-DD')));
+    years := P7(TO_DATE('2003-12-02', 'YYYY-MM-DD'), months, days);
+    DBMS_OUTPUT.PUT_LINE('Age: ' || years || ' Years ' || months || ' Months ' || days || ' Days.');
 END;
 /