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[Ogv]

In our shop we need to add one more column to the existing table and it will be a part of the existing primary key (composite key already).

Can we drop the index and primary key, create index for the whole composite and then create the primaray key for this composite key ?

Or should we drop the table and insert the new col next to the current composite key and then load the old data?

Which option will be a good option performance-wise, maintenance wise?
_________________
Thank-you,
OGV.

[kolusu]

Ogv,

You cannot add a column in the middle without dropping the table.You can add columns at the end without dropping the table.

So in your case you must drop the table and re-create it.

Hope this helps...

cheers

kolusu

[Ogv]

Kolusu,
Thanks for the imm replies.

My question is in detail here.

I am having the table as below.

Table-1
====
col1, col2, col3, col4, col5, col6

Having a composite primary key for the columns col1, col2, col6 will be a problem or not?

Our usual practises are having the first 2/3 columns as primary keys always?

Hope this query should be clear if not the above one.
_________________
Thank-you,
OGV.

[kolusu]

ogv,

Composite key is nothing but an ordered set of key columns of the same table.It is insignificant on the position of the key columns.The key columns need not be adjacent columns.

Performance wise it does not make any difference

Hope this helps...

cheers

kolusu