30. Table - type
30
• ⽇日期
• DATE '0000-00-00'
• TIME '00:00:00'
• DATETIME '0000-00-00 00:00:00’
• TIMESTAMP unix time stamp
• '2038-01-19 03:14:07'
31. select 查詢
31
• SELECT * FROM table_name
WHERE condition // 篩選條件
ORDER BY condition // 排序
GROUP BY condition; // 分組
• SELECT col1, col2, … FROM table_name;
• 「*」 是拿所有欄欄位
33. lab - select where
33
• 找出所有年年齡⼤大於20的⼈人
• SELECT * FROM `employees` WHERE
birth_date < '1999-01-01';
34. select 查詢 AND OR NOT
34
• SELECT * FROM `employees`
WHERE condition1 [AND/OR] condition2;
• WHERE NOT condition;
AND 與 a AND b
OR 或 a OR b
NOT 非 NOT a
35. select 查詢 AND OR NOT
35
• SELECT * FROM `employees`
WHERE birth_date < '1999-01-01'
AND first_name = 'Roy';
• 「⼤大於20歲」且「名字是Roy」的員⼯工
36. lab - AND OR NOT
36
• 找出所有年年齡⼤大於20的⼈人且是女性
• SELECT * FROM `employees`
WHERE birth_date < '1999-01-01'
AND gender = 'F';
37. select 查詢 ORDER BY
37
• SELECT * FROM `employees`
ORDER BY condition [ASC/DESC]
ASC 遞增 (ascending) 0 1 2 3 4 5
DESC 遞減 (descending) 5 4 3 2 1 0
預設是 ASC
38. select 查詢 ORDER BY
38
• SELECT * FROM `employees`
WHERE gender = 'M'
ORDER BY birth_date;
• 男性員⼯工以⽣生⽇日排序
39. lab - select order by
39
• 找出所有年年齡⼤大於20的⼈人且是女性「以年年齡排序」
• SELECT * FROM `employees`
WHERE birth_date <= '1999-01-01'
AND gender = 'F'
ORDER BY birth_date;