The document discusses various SQL statements that can be used in PL/SQL programs including SELECT, INSERT, UPDATE, DELETE, and MERGE. It provides examples of using each statement to retrieve, manipulate, and manage data in Oracle databases. The SELECT statement is used to query data, INSERT adds new rows, UPDATE modifies rows, DELETE removes rows, and MERGE can insert or update rows in a single statement. Joins and cursors are also introduced.

1. Interacting with Oracle Database
Server:
SQL Statements in PL/SQL Programs

2. SELECT Statements in PL/SQL
• SELECT select_list INTO {variable_name[, variable_name]... | record_name}
FROM table [WHERE condition];
• Use the SELECT statement to retrieve data from the database.
– select_list: List of at least one column; can include SQL expressions, row
functions, or group functions
– variable_name: Scalar variable that holds the retrieved value
– record_name:PL/SQL record that holds the retrieved values
– Table: Specifies the database table name
– Condition:
• Ex1:
DECLARE
v_fname VARCHAR2(25);
BEGIN
SELECT custName INTO v_fname
FROM tbCustomer WHERE custID=2;
DBMS_OUTPUT.PUT_LINE(' cust name is : '||v_fname);
END;

3. SELECT Statements in PL/SQL
• EX1:
SELECT EMPID, EMPNAME,GENDER,ADDRESS,DOB,SSID
FROM TBEMPLOYEE;
• EX:SELECT DISTINCT ADDRESS FROM TBEMPLOYEE;
• Ex2:
DECLARE
empName TBEMPLOYEE.EMPNAME%TYPE;
empDob TBEMPLOYEE.DOB%TYPE;
empSalary TBEMPLOYEE.SALARY%TYPE;
BEGIN
SELECT EMPNAME,dob, salary
INTO empName,empDob, empSalary
FROM TBEMPLOYEE
WHERE EMPNAME = 'Chan Da' AND GENDER='Male' AND Address='Phnom Penh';
DBMS_OUTPUT.PUT_LINE ('Name is :'|| empName);
DBMS_OUTPUT.PUT_LINE ('Salary is :'|| empSalary);
DBMS_OUTPUT.PUT_LINE ('DOB is :'|| empDob);
END;

4. Manipulating data with PL/SQL
• Make changes to database tables by using DML commands:
• The INSERT statement adds new rows to the table.
• The UPDATE statement modifies existing rows in the table.
• The DELETE statement removes rows from the table.
• The MERGE statement selects rows from one table to update or insert into another
table.
• EX1:
BEGIN
INSERT INTO employees
(employee_id, first_name, last_name, email,hire_date, job_id, salary)
VALUES(employees_seq.NEXTVAL, 'Ruth', 'Cores','RCORES',CURRENT_DATE, 'AD_ASST',
4000);
END;
EX2:
BEGIN
INSERT INTO TBEMPLOYEE(EMPID,EMPNAME,GENDER, ADDRESS,DOB,SSID,SALARY)
VALUES(4, 'Ruth', 'FEMALE','PHNOM PENH','1-JAN-1979', '112233',123);
END;

5. Manipulating data with PL/SQL
• EX2: Update
DECLARE
sal_increase employees.salary%TYPE := 800;
BEGIN
UPDATE employees
SET salary = salary + sal_increase
WHERE job_id = 'ST_CLERK';
END;
• Ex3:
DECLARE
GENDER_V TBEMPLOYEE.GENDER%TYPE := 'FEMALE';
BEGIN
UPDATE TBEMPLOYEE SET GENDER=GENDER_V WHERE EMPID=4;
END;
• EX3:Delete
DECLARE
deptno employees.department_id%TYPE := 10;
BEGIN
DELETE FROM employees
WHERE department_id = deptno;
END;
EX4:
DECLARE
GENDER_VAR VARCHAR2(20) :='MALE';
BEGIN
DELETE FROM TBEMPLOYEE WHERE
GENDER=GENDER_VAR;
END;

6. Manipulating data with PL/SQL
• Syntax: Merge
BEGIN
MERGE INTO copy_emp c
USING employees e
ON (e.employee_id = c.empno)
WHEN MATCHED THEN
UPDATE SET
c.first_name = e.first_name,
c.last_name = e.last_name,
c.email = e.email,
. . .
WHEN NOT MATCHED THEN
INSERT VALUES(e.employee_id, e.first_name, e.last_name,
. . .,e.department_id);
END;

7. Manipulating data with PL/SQL
• EX4: Merge
BEGIN
MERGE INTO copy_emp c
USING employees e
ON (e.employee_id = c.empno)
WHEN MATCHED THEN
UPDATE SET
c.first_name = e.first_name,
c.last_name = e.last_name,
c.email = e.email,
c.phone_number = e.phone_number,
c.hire_date = e.hire_date,
c.job_id = e.job_id,
c.salary = e.salary,
c.commission_pct = e.commission_pct,
c.manager_id = e.manager_id,
c.department_id = e.department_id
WHEN NOT MATCHED THEN
INSERT VALUES(e.employee_id,
e.first_name, e.last_name,
e.email, e.phone_number, e.hire_date,
e.job_id,
e.salary, e.commission_pct, e.manager_id,
e.department_id);
END;

8. Manipulating data with PL/SQL
• EX5:
BEGIN
MERGE INTO TBEMPLOYEEBACK c
USING TBEMPLOYEE e
ON (e.EMPID = c.EMPID)
WHEN MATCHED THEN
UPDATE SET
c.EMPNAME = e.EMPNAME,
c.GENDER = e.GENDER,
c.ADDRESS = e.ADDRESS,
c.DOB = e.DOB,
c.SSID = e.SSID,
c.SALARY= e.SALARY
WHEN NOT MATCHED THEN
INSERT VALUES(e.EMPID, e.EMPNAME, e.GENDER,
e.ADDRESS, e.DOB, e.SSID, e.SALARY);
END;
EX6:
MERGE INTO bonuses D USING (SELECT
employee_id, salary, department_id FROM
employees WHERE department_id = 80) S
ON (D.employee_id = S.employee_id)
WHEN MATCHED THEN UPDATE SET
D.bonus = D.bonus + S.salary*.01 DELETE
WHERE (S.salary > 8000) WHEN NOT
MATCHED THEN INSERT (D.employee_id,
D.bonus) VALUES (S.employee_id,
S.salary*0.1) WHERE (S.salary <= 8000);

9. Table Relationship
• In SQL Developer, go to View > Data Modeler > Browser. In the Browser view
right click on Relational Models and create a new one. This should create a new
blank diagram. You can drag and drop tables from the Connection view into the
diagram.
• ALTER TABLE TBPRODUCTS ADD
CONSTRAINT FK_PRODUCT_CATE_NUM
FOREIGN KEY (CATEID) REFERENCES TBCATEGORY(CATEID);
• ALTER TABLE TBSALE ADD
CONSTRAINT FK_SALE_CUSTOMER_NUM
FOREIGN KEY (CUSTID)
REFERENCES TBCUSTOMER(CUSTID);

10. Or using wizard by sql developer

11. JOIN operations
• The JOIN operations, which are among the possible TableExpressions in a FROM clause,
perform joins between two tables.
1. INNER JOIN operation: Specifies a join between two tables with an explicit join clause.
SYNTAX:
TableExpression [ INNER ] JOIN
TableExpression { ON booleanExpression | USING clause }
EX1:
SELECT *
FROM TBPRODUCTS INNER JOIN
TBCATEGORY ON
TBPRODUCTS.CATEID = TBCATEGORY.CATEID;
EX2:
SELECT * FROM SAMP.EMPLOYEE
INNER JOIN SAMP.STAFF ON
EMPLOYEE.SALARY < STAFF.SALARY
EX6:
MERGE INTO bonuses D USING (SELECT
employee_id, salary, department_id FROM
employees WHERE department_id = 80) S
ON (D.employee_id = S.employee_id)
WHEN MATCHED THEN UPDATE SET
D.bonus = D.bonus + S.salary*.01 DELETE
WHERE (S.salary > 8000) WHEN NOT
MATCHED THEN INSERT (D.employee_id,
D.bonus) VALUES (S.employee_id,
S.salary*0.1) WHERE (S.salary <= 8000);

12. JOIN operations
• Oracle JOINS are used to retrieve data from multiple tables. An Oracle JOIN is
performed whenever two or more tables are joined in a SQL statement.
• There are 4 different types of Oracle joins:
– Oracle INNER JOIN (or sometimes called simple join)
– Oracle LEFT OUTER JOIN (or sometimes called LEFT JOIN)
– Oracle RIGHT OUTER JOIN (or sometimes called RIGHT JOIN)
– Oracle FULL OUTER JOIN (or sometimes called FULL JOIN)
• INNER JOIN (SIMPLE JOIN)
• Oracle INNER JOINS return all rows from multiple tables where the join condition is
met. Syntax
– SELECT columns FROM table1 INNER JOIN table2 ON table1.column =
table2.column;
Ex1:
SELECT suppliers.supplier_id,
suppliers.supplier_name, orders.order_date
FROM suppliers INNER JOIN orders ON
suppliers.supplier_id = orders.supplier_id;

13. JOIN operations
• Old Syntax
– older implicit syntax as follows (but we still recommend using the INNER JOIN
keyword syntax):
– SELECT suppliers.supplier_id, suppliers.supplier_name, orders.order_date FROM
suppliers, orders WHERE suppliers.supplier_id = orders.supplier_id;

14. JOIN operations
• LEFT OUTER JOIN
– This type of join returns all rows from the LEFT-hand table specified in the ON
condition and only those rows from the other table where the joined fields are
equal (join condition is met).
• Syntax: Oracle LEFT OUTER JOIN is:
• SELECT columns FROM table1 LEFT [OUTER] JOIN table2
ON table1.column = table2.column;
• Ex1:
– SELECT suppliers.supplier_id, suppliers.supplier_name, orders.order_date FROM
suppliers LEFT OUTER JOIN orders ON suppliers.supplier_id = orders.supplier_id;
• Old Syntax
– LEFT OUTER JOIN example above
could be rewritten using the older
implicit syntax that utilizes the outer
join operator (+) as follows
(but we still recommend using the LEFT OUTER JOIN
keyword syntax):
SELECT suppliers.supplier_id, suppliers.supplier_name,
orders.order_date FROM suppliers, orders WHERE suppliers.supplier_id = orders.supplier_id(+);

15. JOIN operations
• Right join returns all rows from the RIGHT-hand table specified in the ON condition
and only those rows from the other table where the joined fields are equal (join
condition is met).
• Syntax
• SELECT columns FROM table1 RIGHT [OUTER] JOIN table2 ON table1.column =
table2.column;
EX:
SELECT orders.order_id, orders.order_date,
suppliers.supplier_name FROM suppliers RIGHT
OUTER JOIN orders ON suppliers.supplier_id =
orders.supplier_id;
Old Syntax:utilizes the outer join operator (+) as follows (but we still
recommend using the RIGHT OUTER JOIN keyword syntax):
SELECT orders.order_id, orders.order_date, suppliers.supplier_name
FROM suppliers, orders WHERE suppliers.supplier_id(+) =
orders.supplier_id;

16. JOIN operations
• FULL OUTER JOIN
• returns all rows from the LEFT-hand table and RIGHT-hand table with nulls in place
where the join condition is not met.
• Syntax
• SELECT columns FROM table1 FULL [OUTER] JOIN table2 ON table1.column =
table2.column;
Ex:
SELECT suppliers.supplier_id, suppliers.supplier_name,
orders.order_date FROM suppliers FULL OUTER JOIN
orders ON suppliers.supplier_id = orders.supplier_id;

17. Introducing SQL cursors
• EX4: Merge
BEGIN
MERGE INTO copy_emp c
USING employees e
ON (e.employee_id = c.empno)
WHEN MATCHED THEN
UPDATE SET
c.first_name = e.first_name,
c.last_name = e.last_name,
c.email = e.email,
c.phone_number = e.phone_number,
c.hire_date = e.hire_date,
c.job_id = e.job_id,
c.salary = e.salary,
c.commission_pct = e.commission_pct,
c.manager_id = e.manager_id,
c.department_id = e.department_id