Slide 13
Slide 13 text
·ͣSQLΛࢼͯ͠ΈΑ͏
SELECT count(*) FROM employees;
- 300,024݅
SELECT count(*) FROM employees WHERE hire_date >= ‘1990-01-01';
- 135,227݅
SELECT * FROM employees LIMIT 200;
- 200 rows in set (0.00 sec)
ɹ
SELECT * FROM employees
WHERE hire_date >= ‘1990-01-01’ ORDER BY hire_date desc LIMIT 200;
- 200 rows in set (0.15 sec)
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