Re: What is an overflow segment?

You need the book !

An IOT is basically a primary key index, with all the extra columns attached to the index entry. But this means that your index entries could get very large.

If your rows are large (which means defined as being able to exceed 50 percent of a block), then Oracle insists that you specify an overflow data segment for the excess columns. In effect the IOT turns back into a table (overflow) with a primary key index - but with some of the table columns stored in the index.

It would appear that Axapta has a table defined as an IOT, without making any allowance for an Overflow. Presumably they installed it once on their test systems, but you can't because your block size is smaller than their original block size.

In the simplest case, you could probably get away with simply add the key word OVERFLOW to the CREATE TABLE statement.

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Dino Hsu wrote in message ...


>Dear all,

>

>When we are in the process of installing Axapta (an ERP from Europe),

>we encounter the following error message (with explanation from the

>doc):

>

>"ORA-01429 Index-Organized Table: no data segment to store overflow

>row-pieces

>

>Cause: No overflow segment defined.

>

>Action: Add overflow segment."

>

>The problem is I don't know anything about an overflow segment,

>although I did learn IOT before. I checked Kevin Loney, Jason Couchman

>and Noel Yuhanna books, no overflow segment is mentioned (sorry

>Jonathan, don't have your book yet). Although there are some material

>in the doc and metalink, but I still cannot figuer out a basic idea

>about it. I need straight and basic definition about what an overflow

>segment is. Anyone helps me out? Thanks in advance.

>

>Dino

>