SQL query statement

The basic query

1. Specified field

select  Field A, Field B from  surface 

2. Query all fields

select * from  surface 

Query data filtering

1. Simple filtering

Operator	Example
=	id = 1
!= or <>	sex != 1
>= 、> 、<、<=	salary > 1000
BETERRN	salary between 100 and 200
IN	name IN(‘ Cherish ’,‘ Barbarian ’)

2. A null value judgment

select * from user where name is null

3. Text blur
   Use like matching ,% matching 0 Or more than one character ,_ Match a character

select * from user where name like '%i'

4. Combinatorial logic
   AND OR NOT
5. duplicate removal
   DISTINCT

Sort

order by –

ASC： Ascending （ Default ）
DESC： Descending

Qualified result set

Here is mysql How to write a sentence ,limit Specify the quantity ,offset Specify where to start , That's the offset , The default is 0 Start

select  Field  from  Table name  order by  Field  limit a offset b

notes

• – Two hyphens
• /* */ Used for multi line comments