create table user
(
    id NUMBER comment '主键',
    name VARCHAR2(100) comment '姓名',
    email VARCHAR2(100) comment '邮箱',
    gender VARCHAR2(2) default '男' comment '性别'
);

-- Add comments to the table
ALTER TABLE user COMMENT '用户表';

-- Create primary
alter table user add primary key (id);

-- Create indexes
create index idx_name on user(name);
create index idx_name_email on user(name,email);