In mysql, you can use the SELECT statement with the specified field name to query the value of a field. The syntax is "SELECT field name FROM table name WHERE clause LIMIT clause;".
The operating environment of this tutorial: windows7 system, mysql8 version, Dell G3 computer.
In mysql, you can use the SELECT statement with the specified field name to query the value of a field.
The syntax format of a field in the query table is:
SELECT 列名 FROM 表名 [WHERE <表达式> [GROUP BY[HAVING [{ }…]] [ORDER BY ] [LIMIT[ ,] ] ]
WHERE
GROUP BY< Field >, this clause tells MySQL how to display the queried data and group it according to the specified field.
[ORDER BY< field>], this clause tells MySQL in what order to display the queried data. The possible sorting is ascending order (ASC) and descending order (DESC ), which is ascending by default.
Example 1:
Query the names of all students in the name column of the tb_students_info table. The SQL statement and running results are as follows.mysql> SELECT name FROM tb_students_info; +--------+ | name | +--------+ | Dany | | Green | | Henry | | Jane | | Jim | | John | | Lily | | Susan | | Thomas | | Tom | +--------+ 10 rows in set (0.00 sec)
SELECT <字段名1>,<字段名2>,…,<字段名n> FROM <表名>;
Example 2:
Get the three columns of id, name and height from the tb_students_info table. The SQL statement and running results are as follows shown.mysql> SELECT id,name,height -> FROM tb_students_info; +----+--------+--------+ | id | name | height | +----+--------+--------+ | 1 | Dany | 160 | | 2 | Green | 158 | | 3 | Henry | 185 | | 4 | Jane | 162 | | 5 | Jim | 175 | | 6 | John | 172 | | 7 | Lily | 165 | | 8 | Susan | 170 | | 9 | Thomas | 178 | | 10 | Tom | 165 | +----+--------+--------+ 10 rows in set (0.00 sec)
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