DDL operation table structure

By Mysql

DDL operation table structure: CRUD

One, C (create) create

　　1, create table 

create table table name(
   Column name 1 data type 1,
   Column name 2 data type 2,
   Column name 3 data type 3,
   ...
   Column name n data type n
);

　　Note: The last column, no need to add a comma (,)

　　2, copy table

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create table table name like the name of the copied table;

　　3, MySQL data type

　　　 Common data types:

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　　 Detailed data type:

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　　Note< /strong>: timestamp: timestamp type, including year, month, day, hour, minute and second yyyy-MM-dd HH:mm:ss, if not in the future Assign a value to this field, or assign it to null, the current system time will be used by default to automatically assign the value

Second, R (Retrieve) query

　　1. Query all table names in a database

show tables;

　　2, query table structure

desc table name;

　　3. View the SQL statement to create the table

show create table table name;

　　

3. U (Update) modification

　　1 , Modify the table name

alter table Table name rename to new table name

　　2, modify the character set of the table

alter table table name character set character set name;

　　3, add a column

alter table table name add column name data type

　　4. Modify the column name type

alter table table name change column name new column name new data type;
alter table table name modify alias new data type;

　　5, delete column

alter table table name drop column name

　　

Four. D (Delete) delete

　　1 , Delete table

drop table Name;

　　2, determine whether the table exists, and then delete it after it exists

drop table if exists table name;


create table name(
   Column name 1 data type 1,
   Column name 2 data type 2,
   Column name 3 data type 3,
   ...
   Column name n data type n
);


create table table name like is copied The name of the table;


show tables; 

desc table name;


show create table table name;


alter table rename to new Table name

alter table table name character set character set name;

alter table table name add column name data type

alter table table name change column name new column name new data type;
alter table table name modify alias new data type;

alter table table name drop column name


drop table table name;

drop table if exists table name;

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