The new database the create database

The new form the create table

Delete the database drop database

Query selecr * from

Primary key constraint primary key

The only constraints unique

Automatic growth auto_increment

Not empty the not null

The default constraints default default value

Insent insert data into the table name (the column 1, column 2, column 3,... ) values (number 1 and number 2, number 3,... );

Modify the data update table name set to be modify the field name=new value, to be modify the field name=new value,... Where

Modify all the data in the table sample update studentinfo set age=age + 1;


Delete records delete (delete all data in the table)

Delete the data sample dalete the from table name where
Delete all the data in the table, leaving a structure definition

Truncate tabale table name;

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