Answer / gk

We can use Check constraint to restict the values of any
column.

Answer / suresh babu

create check constraint is the best way to restrict the
limited number of entries,because the constraint won't take
a separate space,but Trigger required separate memory
space.perhaps the trigger got error,it would affect all
entries in table.

Answer / guest

hint:using row level and statement level trigger

Answer / bikash khuntia

We have to create a trigger for that which is one of the
way for the solutuion as below:-

create or replace trigger trigger_name
before insert on table_name
for each row
DECLARE
v_count number;
begin
select count(apple) into v_count from table_name;
if v_count=100 then
raise_application_error('-20011','u cant insert more than
100 apples in the table');
end if;
end;

Answer / ashwin

You can create a sequence named seq_fruit as below .

create sequence seq_fruit
increment by 1
start with 1
maxvalue 100
minvalue 1
cycle
cache 10
if the current count ie currval of seq_fruit is 100 and
after this if u r inserting a new row in fruit table as
following

insert into fruit values(seq_fruit.nextval,30,40);
after the execution of this statement next value for apple
will be entered as 1 and not 101.

The cycle keyword will avoid the count of fruit column to go
beyond 100.

Answer / xyz

aLTER TABLE emp ADD CONSTRAINT C3 CHECK (EMPNO < 300)

Can variables be used in sql statements?

0 Answers  

Interchange the value of a column Gender in a table where values are Male and Female. So, where the value is Male, it should changed to Female and Female to Male.

4 Answers   Cap Gemini, IBM,

Are stored procedures faster than queries?

0 Answers  

select 1,col1,col2 from table1. output?

5 Answers   Ramco,

What is TABLE SPACE?

4 Answers   ABB, TCS,

Is truncate ddl or dml?

0 Answers  

What is the purpose of using pl/sql?

0 Answers  

using comand prompt how can import table data and table space with example

2 Answers  

what is explain plan?, given an example...

3 Answers   Polaris,

Is primary key an index?

0 Answers  

I want to display the employees who have joined in last two months. (It should be executed randomly means If I execute the query in March it should display Jan and Feb joined employees. Same query if i execute in Feb, 2007 it should display dec, 2006 and jan 2007 joined employees.

15 Answers   Wipro,

Is sql port 1433 encrypted?

0 Answers