修改表名:alter table table_name rename new_table_name; 添加字段:alter table table_name add column_name type_name constraint_name 修改字段:alter table table_name modify column_name type_name constraint_name 删除字段:alter table table_name drop column_name 约束: 主键: 单主键添加: create table table_name(column primary key,...); alter table table_name add constraint pk_name primary key (column); 多主键添加: create table table_name(column ...,primary key (column...)); alter table table_name add constraint pk_name primary key (column...); 主键删除: alter table table_name drop primary key; 外键: 外键创建: create table table_name(column ...,constraint fk_name foreign key (column) references table_name(column)); alter table productinfo add constraint fk_name foreign key (column) references table_name(column); 外键删除: alter table table_name drop foreign key fk_name; 默认: 创建: create table table_name(column default value,...); alter table table_name alter column set default value; 删除: alter table table_name alter column drop default; 非空: 创建: create table table_name(column NOT NULL,...); alter table table_name modify/alter column NOT NULL; 检查: 创建: create table table_name(column check(expression),...); create table table_name(column ...,[constraint constraint_name]check(expression)); alter table table_name add constraint check_name check(expression); 唯一: 创建: create table table_name(column unique,...); create table table_name(column ...,[constraint constraint_name]unique(column)...); create table table_name(column ...,[constraint constraint_name]unique(column...)); alter table table_name add constraint unique_name unique(column...); 删除: drop index unique_name on table_name;