Query Help

[anupamasuresh]

Hi,
Can anyone give me solution for these question:

IS there any way we can retrieve alternate rows in a table(1,3,5,...)?

What is the maximum number of triggers we can write on a table?

Thanks All in advance
Anupama

[jmodic]

Originally posted by anupamasuresh
IS there any way we can retrieve alternate rows in a table(1,3,5,...)?

What are those 1,3,5,... values? If they are for example values from some column (like sequence generated keys), you can us this:

SELECT * FROM my_table
WHERE MOD(my_column, 2) = 1;

If on the other hand you simply would like to display every other record that is otherwise returned by the query, you can use this:

SELECT * FROM
(SELECT ROWNUM rn, x.* FROM my_table x)
WHERE MOD(rn, 2) = 1;

What is the maximum number of triggers we can write on a table?

Don't think there is a limit on this (at least not a practical one).

[DaPi]

1) something like:

select * from
(select a.*, Rownum row_number
 from my_table a)
where mod(row_number,2)=1

2) since you can't determine the sequence of triggers firing, I'd prefer one trigger which calls a heap of procedures.