How can I combine different rows?

[hlajeunessse]

Hi!

I have a table looking like

(username) (account number) (start date) (end date) (product)

wich I can have up to 4 lines for the same client.

I wist to transfert those lines into a new table looking like

(username) (account number) (start date 1) (end date 1) (product 1)
(start date 2) (end date 2) ... (product 4)

How (in SQL) I could do it?

[--CELKO--]

>I have a table looking like ..

Please post DDL instead of your personal narrative. If you had done
the talbe properly, i mgiht look like this:

CREATE TABLE AccountHistory
(acct_nbr INTEGER NOT NULL,
product_nbr INTEGER NOT NULL,
product_cnt INTEGER DEFAULT 1 NOT NULL
CHECK(product_cnt BETWEEEN ! AND 4),
PRIMARY KEY (acct_nbr, product_nbr, product_cnt),
user_name VARCHAR(25) NOT NULL,
start_date DATETIME NOT NULL,
end_date DATETIME NOT NULL,
CHECK (start_date < end_date));

I left out the REFERENCES clause you would need and some other
things.

>which I can have up to 4 lines [sic] for the same client. <<

Lines appear on a paper form or an input screen; a table has rows.
You need a constraint to enforce this rule.

>I wish to transfer those lines into a new table looking like .. <<

You also failed to give any rules for sorting the repeating groups.
But th real question is why are you doing this at all?? That would
violate First Normal Form (1NF). This is not a good way to write
SQL.