oracle与mysql创建表时的区别

TABLE predict_data as ( id integer NOT NULL,
uid varchar2(80), mid varchar2(80), time date , content varchar2(300), constraint predict_data primary key (id) );
#字段注释
comment on table predict_data is ‘预测表‘;
comment on column predict_data.id is ‘主键‘;
comment on column predict_data.uid is ‘用户名‘;
comment on column predict_data.mid is ‘博文id‘;
comment on column predict_data.time is ‘发文时间‘;
comment on column predict_data.content is ‘发文内容‘;

mysql创建表时，支持在建表时同时增加字段注释。故采用以下方式：

CREATE TABLE predict_data (
  id               int                NOT NULL     COMMENT ‘主键‘, 
  uid               varchar(80)      NOT NULL     COMMENT ‘用户标记‘,
  mid               varchar(80)      DEFAULT NULL COMMENT    ‘博文标记‘    ,
  time              datetime          DEFAULT NULL COMMENT    ‘发博时间‘    ,
  content        varchar(300)   DEFAULT NULL COMMENT    ‘博文内容‘    ,
  CONSTRAINTpredict_data PRIMARY KEY (id),
) ENGINE=InnoDB DEFAULT CHARSET=gbk COLLATE=gbk_bin;

注意：mysql在建立表的时候，不能使用as，即不能使用create table tablename as，否则报错“1064 - You have an error in your SQL syntax;”

oracle与mysql创建表时的区别

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