mysql select where
时间: 2023-05-02 19:02:53 浏览: 57
问题:什么是MySQL中的“select where”语句?
回答:MySQL中的“select where”是一种SQL查询语句,用于从表中选择符合特定条件的记录。语法为:“SELECT column_name(s) FROM table_name WHERE condition”。条件可以是任何表中的列与值之间的比较,如等于、大于、小于、包含等。通过“select where”语句,可以快速定位并提取需要的数据。
相关问题
mysql select from where when
The "SELECT FROM WHERE" clause is used in MySQL to retrieve data from a table based on certain conditions.
Here is an example of how to use the SELECT FROM WHERE clause in MySQL:
```
SELECT column1, column2, ...
FROM table_name
WHERE condition;
```
- "column1, column2, ..." are the columns that you want to retrieve data from.
- "table_name" is the name of the table that you want to retrieve data from.
- "condition" is the condition that you want to apply to retrieve data.
For example, to retrieve all the rows from the "users" table where the age is greater than or equal to 18, you can use the following query:
```
SELECT * FROM users WHERE age >= 18;
```
This will retrieve all the columns and rows from the "users" table where the age is greater than or equal to 18.
mysql select from where in
`SELECT` 语句用于从数据库中检索数据。`WHERE` 子句用于指定检索条件。`IN` 运算符用于指定范围,它允许您指定多个值作为搜索条件。
语法如下:
```
SELECT column_name(s) FROM table_name WHERE column_name IN (value1, value2, ...);
```
例如,从 `employees` 表中选择工资为 20000 或 25000 的员工:
```
SELECT * FROM employees WHERE salary IN (20000, 25000);
```