IST466: Altering tables in Oracle

Altering tables in Oracle

Please run the following SQL commands. For each command explain what it does and also the Oracle output. Pay especially attention to error messages.

create table TROUBLE (
  City  varchar(13)  not null,
  SampleData date  not null,
  Noon  number(4,1),
  Midnight number(4,1),
  constraint TROUBLE_UQ unique (City, SampleData)
);

insert into trouble values ('Huntington', to_date('08-22-02', 'MM-DD-YY'), 12.23, 44.999);

alter table trouble add (
  Wind  number(3)
);

alter table trouble add(
  Condition varchar(9) not null
);

alter table trouble add(
  Condition varchar(9)
);

```
update trouble set Condition='Sunny';
```

alter table trouble modify (Condition varchar(9) not null);

```
desc trouble;
```

alter table trouble modify (Condition null);

```
desc trouble;
```

alter table trouble add (
  population number check (population >=1000)
);

alter table trouble add (
  age date constraint trouble_age check (age >= to_date('08-22-1564', 'MM-DD-YYYY') )
);

insert into trouble (City, Sampledata, age)
  values ('Huntington', SysDate,  to_date('08-22-1000', 'MM-DD-YYYY'));

 insert into trouble (City, Sampledata, age)