Constant sets
To establish a view for the individual income tax rate worksheet:
| Level | Taxable Income | Tax Rate | Deduction |
| 1 | 500 | 5% | 0 |
| 2 | 2000 | 10% | 25 |
| 3 | 5000 | 15% | 125 |
| 4 | 20000 | 20% | 375 |
SQL
CREATE VIEW tax_rate AS
SELECT 1 level, 500 payable_inc, 0.05 tax_rate, 0 deduction
FROM dual UNION
SELECT 2, 2000, 0.1, 25 FROM dual UNION
SELECT 3, 5000, 0.15, 125 FROM dual UNION
SELECT 4, 20000, 0.2, 375 FROM dual
The text-style SQL code cannot neatly align the constants presented in the table.
SPL
| A | B | C | D | |
| 1 | 1 | 500 | 5% | 0 |
| 2 | 2 | 2000 | 10% | 25 |
| 3 | 3 | 5000 | 15% | 125 |
| 4 | 4 | 20000 | 20% | 375 |
| 5 | =create(level,payable_inc,tax_rate,deduction).record([A1:D4]) | |||
The grid-style SPL code displays the data in a more intuitive and neater way.
In order to simplify the SQL statement as much as possible in the examples, the window functions of SQL 2003 standard are widely used, and accordingly the Oracle database syntax which has best support for SQL 2003 is adopted in this essay.
