MySQL database query operation

Data Query Language

SELECT column name 1, column Name 2 ... from table name [where condition]

Query all fields use * to isolate all records of a table without a Where condition

=//Assignment and judgment are

! = <>//Two types not equal to

< > <= >=

OR OR | |

and &&

Between 5 and 10

Inch

Not in

Like '% value% '

For some simple queries, take the user table for example, sex-"0 for Male, 1 for female

1. Query all

Sleect * from user

2. Query for data with age 33

SELECT * from user where age=33;

3. Query sex is not a male data

SELECT * from user where sex!=0;

4. Querying for data older than 30

SELECT * from user where age>30

5. Query for age=30 or age=40 data

SELECT * from user where age=30 or age=40;

6. Querying age=40 and user_name=liming data

SELECT * from user where age=40 and user_name= ' liming ';

MySQL database query operation