丢弃唯一键并生成新的唯一键

Question

我在oracle数据库中创建了一个表，我的表脚本是

  CREATE TABLE wsc_widget_bundle (
    id VARCHAR (50),
    widgetBundle BLOB NULL, 
    devicesoftwareclass VARCHAR(30) NOT NULL,
    widgetProfileId VARCHAR (50) NOT NULL,
    bundleHash BLOB NULL,
    widgetLocale VARCHAR (6) NOT NULL ,
    status INT,  
        primary key(id),
        unique(widgetProfileId, devicesoftwareclass,status),
    foreign key(widgetProfileId) references wsc_widget_profile(id)
  );

当我为它创建ddl时，它看起来像这样

create table "DEV1"."WSC_WIDGET_BUNDLE"(
    "ID" VARCHAR2(50) not null,
   "WIDGETBUNDLE" BLOB,
   "DEVICESOFTWARECLASS" VARCHAR2(30) not null,
   "WIDGETPROFILEID" VARCHAR2(50) not null,
   "BUNDLEHASH" BLOB,
   "WIDGETLOCALE" VARCHAR2(6) not null,
   "STATUS" NUMBER,
    constraint "SYS_C00323290" primary key ("ID")
);

alter table "DEV1"."WSC_WIDGET_BUNDLE"  
    add constraint "SYS_C00323292" 
    foreign key ("WIDGETPROFILEID") 
    references "MTP440_DEV1"."WSC_WIDGET_PROFILE"("ID");
create unique index "MTP440_DEV1"."SYS_C00323290" on "MTP440_DEV1"."WSC_WIDGET_BUNDLE"("ID");
create unique index "MTP440_DEV1"."SYS_C00323291" on "MTP440_DEV1"."WSC_WIDGET_BUNDLE"("WIDGETPROFILEID","DEVICESOFTWARECLASS","STATUS");
create index "MTP440_DEV1"."TEST" on "MTP440_DEV1"."WSC_WIDGET_BUNDLE"("DEVICESOFTWARECLASS","STATUS","WIDGETLOCALE","WIDGETPROFILEID");

现在，我想要编写alter脚本来更改我表的唯一键约束，但是在创建表时，我没有提到我的唯一键名的名称，它是由SYS_C00323291之类的系统提供的，那么我如何编写alter脚本来删除名称未知的唯一键并生成新的键

Answer 1

您可以通过查询user_constraints和user_cons_columns视图来查找约束的名称。

Answer 2

Alter table x
drop constraint pk;

Alter table x
add constraint New_constraint_name PRIMARY KEY (colname);