Sequenced transactiontime

Database
Enthusiast

Sequenced transactiontime

Hi

What is meant by SEQUENCED VALIDTIME clause in a query on temporal table ?What does exactly SEQUENCED clause do? On the same light, please can anyone explain why is SEQUENCED TRANSACTIONTIME not permissible ?

Thanks in advance.

1 REPLY
Enthusiast

Re: Sequenced transactiontime

Refer to the Temporal Manual (pg 26 for TD14.0).

"A sequenced query produces a temporal table as a result set."   I have been using this in views, and as the result set is temporal, I can then ask "AS OF" type queries of the view.  I can also see all of the valid records for a given key.  The temporal sql extensions work on a Sequenced VALIDTIME result set (CURRENT, AS OF, etc).

Nonsequenced results sets still give you the same set of rows, but the Period column you added is now just another column.  You can not ask a "AS OF" query in a nonsequenced dataset - well you could use normal Period clauses in your query (CONTAINS, PRECEDES, etc) but not the "out of the box" temporal features.

Also, see my other post at:

http://forums.teradata.com/forum/database/create-compound-temporal-view-to-allow-as-of-reporting

Can someone answer the second question:   Why is it not permissible ?