Tutorial by Examples

SELECT 'Hello world!' FROM dual; In Oracle's flavor of SQL, "dual is just a convienence table". It was originally intended to double rows via a JOIN, but now contains one row with a DUMMY value of 'X'.

Create a simple table create table MY_table ( what varchar2(10), who varchar2(10), mark varchar2(10) ); Insert values (you can omit target columns if you provide values for all columns) insert into my_table (what, who, mark) values ('Hello', 'world', '!' ); insert into my_table ...

List employees earning more than $50000 born this century. List their name, date of birth and salary, sorted alphabetically by name. SELECT employee_name, date_of_birth, salary FROM employees WHERE salary > 50000 AND date_of_birth >= DATE '2000-01-01' ORDER BY employee_name; Show...

/* PL/SQL is a core Oracle Database technology, allowing you to build clean, secure, optimized APIs to SQL and business logic. */ set serveroutput on BEGIN DBMS_OUTPUT.PUT_LINE ('Hello World!'); END;