Practise-- Oracle

CREATE OR REPLACE PROCEDURE raise_emp_salary (column_value NUMBER,
emp_column VARCHAR2, amount NUMBER) IS
v_column VARCHAR2(30);
sql_stmt VARCHAR2(200);
BEGIN
-- determine if a valid column name has been given as input
SELECT COLUMN_NAME INTO v_column FROM USER_TAB_COLS
WHERE TABLE_NAME = 'EMPLOYEES' AND COLUMN_NAME = emp_column;
sql_stmt := 'UPDATE employees SET salary = salary + :1 WHERE '
|| v_column || ' = :2';
EXECUTE IMMEDIATE sql_stmt USING amount, column_value;
IF SQL%ROWCOUNT > 0 THEN
DBMS_OUTPUT.PUT_LINE('Salaries have been updated for: ' || emp_column
|| ' = ' || column_value);
END IF;
EXCEPTION
WHEN NO_DATA_FOUND THEN
DBMS_OUTPUT.PUT_LINE ('Invalid Column: ' || emp_column);
END raise_emp_salary;
/

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DECLARE
plsql_block VARCHAR2(500);
BEGIN
-- note the semi-colons (;) inside the quotes '...'
plsql_block := 'BEGIN raise_emp_salary(:cvalue, :cname, :amt); END;';
EXECUTE IMMEDIATE plsql_block USING 110, 'DEPARTMENT_ID', 10;
EXECUTE IMMEDIATE 'BEGIN raise_emp_salary(:cvalue, :cname, :amt); END;'
USING 112, 'EMPLOYEE_ID', 10;
END;
/

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DECLARE
sql_stmt VARCHAR2(200);
v_column VARCHAR2(30) := 'DEPARTMENT_ID';
dept_id NUMBER(4) := 46;
dept_name VARCHAR2(30) := 'Special Projects';
mgr_id NUMBER(6) := 200;
loc_id NUMBER(4) := 1700;
BEGIN
-- note that there is no semi-colon (;) inside the quotes '...'
EXECUTE IMMEDIATE 'CREATE TABLE bonus (id NUMBER, amt NUMBER)';
sql_stmt := 'INSERT INTO departments VALUES (:1, :2, :3, :4)';
EXECUTE IMMEDIATE sql_stmt USING dept_id, dept_name, mgr_id, loc_id;
EXECUTE IMMEDIATE 'DELETE FROM departments WHERE ' || v_column || ' = :num'
USING dept_id;
EXECUTE IMMEDIATE 'ALTER SESSION SET SQL_TRACE TRUE';
EXECUTE IMMEDIATE 'DROP TABLE bonus';
END;
/
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select dbms_metadata.get_ddl('PACKAGE_BODY','PACKAGE_NAME') from dual;

select dbms_metadata.get_ddl('PACKAGE_SPEC','PACKAGE_NAME') from dual;

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