Common basic MySQL operations

No details about MySQL? # Common basic operations of the MySQL database SQL (StructuredQueryLanguage) Structured Query Language: * DDL (DataDefinitionLanguage) Data Definition Language * # create a database: createdatabase database name charsetutf8; # delete a database: dropdatabase database name; # display

No details about MySQL? # Common basic operations of the Structured Query Language (Structured Query Language) Structured Query Language in MySQL:/* Data Definition Language (DDL) */# create a database: create database 'database name' charset utf8; # delete a database: drop database 'database name'; # display

<无详细内容> MySQL

? # Common basic operations of the Structured Query Language (Structured Query Language) Structured Query Language in MySQL:/* Data Definition Language (DDL) */# create a database: create database 'database name' charset utf8; # delete database: drop database 'database name'; # display all databases: show databases; # use database 'database name '; # determine the currently used database: select database (); # desc 'table name' of a table structure in the database; # show the table creation statement show create table 'table name '; # create a table: create table 'table name' ('column name' 'column description', 'column name', 'column name '); # create table 'table name' ('column name' column description 'Primary key auto_increment, 'column name' 'column description ', 'column name' 'column description'); # delete a table: drop table 'table name'; # modify a table: alter table 'old table name' rename' new table name '; # add field alter table 'table name' add column 'column name' 'column description '; # modify the field "alter table" table name "change" old column name "new column name" "new column description"; # Delete the field "alter table" table name "drop column name" column name '; /* DML (Data Manipulation Language) Data operation Language */# insert into 'table name' ('field name, field name... ') values (' corresponding value, corresponding value... '); insert into' table name' values ('corresponding value, corresponding value... '); # update data Update' table name 'set' field name' = 'field value', 'field name' = 'field value '... where 'field name' = 'field value'; Update' table name'set' field name' = 'field value', 'field name' = 'field value '...; # delete Data from 'table name'; delete from 'table name' where 'field name' = 'field value';/* DQL (Data Queries Language) data Query Language */# query all select * from 'table name'; # query the required select 'field name', 'field name '... from 'table name'; # Alias query select 'field name', concat ('field name', 'field name') [as] 'Alias 'from' table name '; # where query select * from 'table name' where 'field name' like "_ 'value' %" # Aggregate Query select count (*) from 'table name '; # query the number of records select 'field name' from 'table name' order by 'field name' desc; # query select distinct 'field name' from 'table name' order by 'field name' asc in descending order; # duplicate query in ascending order # select avg ('field name') from 'table name' group by 'field name'; select avg (field name) as 'Alias ', 'Alias 'from 'field name' group by 'field name' having 'field name'> 0;/* DCL (Data Control Language) data Control Language * // * constraint */# primary key constraint alter table 'table name' add constraint primary key ('field name '); # unique constraint alter table 'table name' add constraint unique ('field name '); # foreign key constraint alter table 'table name' add constraint foreign key ('foreign key field name') references 'Primary table' ('Primary key field name ');