Summary of MySQL's commonly used SQL statements for creating tables, adding fields, modifying fields, and adding indexes

DROP TABLE IF EXISTS bulletin;
CREATE TABLE bulletin(
 id INT NOT NULL PRIMARY KEY AUTO_INCREMENT, # Primary key uid INT(11) NOT NULL DEFAULT 0, # Creator id
 context VARCHAR(600) NOT NULL DEFAULT '', # Announcement details (300 words)
 begintime DEC(20) NOT NULL DEFAULT 0, # Announcement start time endtime DEC(20) NOT NULL DEFAULT 0, # Announcement end time createtime DEC(20) NOT NULL DEFAULT 0, # Creation time modifytime DEC(20) NOT NULL DEFAULT 0 # Modification time PRIMARY KEY (`Id`),
)DEFAULT CHARSET=UTF8 TYPE=INNODB;

ALTER TABLE bulletin CHANGE uid username VARCHAR(50) NOT NULL DEFAULT '';

alter table bulletin add citycode varchar(6) not null default 0; # city code

create database test character set utf8;

create table test(id int primary key)DEFAULT charset=utf8;

alter database test character set utf8;

alter table test character set utf8;

alter table test modify col_name varchar(50) CHARACTER SET utf8;

mysql>ALTER TABLE `table_name` ADD PRIMARY KEY (`column`)

mysql>ALTER TABLE `table_name` ADD UNIQUE (
`column`
)

mysql>ALTER TABLE `table_name` ADD INDEX index_name (`column`)

mysql>ALTER TABLE `table_name` ADD FULLTEXT (
`column`
)

mysql>ALTER TABLE `table_name` ADD INDEX index_name ( `column1`, `column2`, `column3` )