sql教程4 MySQL SELECT

sql快速入门教程1简介

sql教程2数据库和SQL简介

sql教程3 MySQL介绍

sql教程4 MySQL SELECT

sql教程5插入和删除及更新

sql教程6分组、转义与模糊匹配、正则表达式

sql教程7函数

sql教程8 NULL ALTER DROP RENAME LIMIT

SQL SELECT语法

SELECT [DISTINCT|ALL ] { * | [fieldExpression [AS newName]} FROM tableName [alias] [WHERE condition][GROUP BY fieldName(s)]  [HAVING condition] ORDER BY fieldName(s)

数据库

mysql> SELECT Concat(`title`, ' (', `director`, ')') , `year_released` FROM `movies`;
+---------------------------------------------+---------------+
| Concat(`title`, ' (', `director`, ')')      | year_released |
+---------------------------------------------+---------------+
| Pirates of the Caribean 4 ( Rob Marshall)   |          2011 |
| Forgetting Sarah Marshal (Nicholas Stoller) |          2008 |
| NULL                                        |          2008 |
| Code Name Black (Edgar Jimz)                |          2010 |
| NULL                                        |          2007 |
| NULL                                        |          2007 |
| NULL                                        |          2007 |
| Honey mooners (John Schultz)                |          2005 |
| NULL                                        |          2012 |
| The Great Dictator (Chalie Chaplie)         |          1920 |
| movie 3 (John Brown)                        |          1920 |
+---------------------------------------------+---------------+
11 rows in set (0.04 sec)

mysql> SELECT Concat(`title`, ' (', `director`, ')') AS 'Concat', `year_released` FROM `movies`;
+---------------------------------------------+---------------+
| Concat                                      | year_released |
+---------------------------------------------+---------------+
| Pirates of the Caribean 4 ( Rob Marshall)   |          2011 |
| Forgetting Sarah Marshal (Nicholas Stoller) |          2008 |
| NULL                                        |          2008 |
| Code Name Black (Edgar Jimz)                |          2010 |
| NULL                                        |          2007 |
| NULL                                        |          2007 |
| NULL                                        |          2007 |
| Honey mooners (John Schultz)                |          2005 |
| NULL                                        |          2012 |
| The Great Dictator (Chalie Chaplie)         |          1920 |
| movie 3 (John Brown)                        |          1920 |
+---------------------------------------------+---------------+
11 rows in set (0.00 sec)

mysql> SELECT `membership_number`,`full_names`,LEFT(`date_of_birth`,4) AS `year_of_birth` FROM members;
+-------------------+---------------------+---------------+
| membership_number | full_names          | year_of_birth |
+-------------------+---------------------+---------------+
|                 1 | Janet Jones         | 1980          |
|                 2 | Janet Smith Jones   | 1980          |
|                 3 | Robert Phil         | 1989          |
|                 4 | Gloria Williams     | 1984          |
|                 5 | Leonard Hofstadter  | NULL          |
|                 6 | Sheldon Cooper      | NULL          |
|                 7 | Rajesh Koothrappali | NULL          |
|                 8 | Leslie Winkle       | 1984          |
|                 9 | Howard Wolowitz     | 1981          |
+-------------------+---------------------+---------------+
9 rows in set (0.00 sec)

mysql> SELECT * FROM members WHERE membership_number IN (1,2,3);
+-------------------+-------------------+--------+---------------+------------------------+----------------+----------------+---------------------+
| membership_number | full_names        | gender | date_of_birth | physical_address       | postal_address | contact_number | email               |
+-------------------+-------------------+--------+---------------+------------------------+----------------+----------------+---------------------+
|                 1 | Janet Jones       | Female | 1980-07-21    | First Street Plot No 4 | Private Bag    | 0759 253 543   | [email protected] |
|                 2 | Janet Smith Jones | Female | 1980-06-23    | Melrose 123            | NULL           | NULL           | [email protected]      |
|                 3 | Robert Phil       | Male   | 1989-07-12    | 3rd Street 34          | NULL           | 12345          | [email protected]      |
+-------------------+-------------------+--------+---------------+------------------------+----------------+----------------+---------------------+
3 rows in set (0.03 sec)

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