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Archives of the TeradataForum
Message Posted: Mon, 23 Jul 2012 @ 13:32:59 GMT
| Subj: | | Re: What does TOP actually mean? |
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| From: | | Walter, Todd |
A specific AMP will be chosen based on the tableid, then rows will be taken from the beginning of the data in that AMP which means they will be
returned by rowid order - since the table is in that order already.
If a row is inserted that happens to hash low in that amp, it will change the result returned. If there are not enough rows in that amp to
satisfy the request, then a different mechanism is used that will have different behavior and will be much less predictable.
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