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You're reading from  Developing Robust Date and Time Oriented Applications in Oracle Cloud

Product typeBook
Published inMay 2023
PublisherPackt
ISBN-139781804611869
Edition1st Edition
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Author (1)
Michal Kvet
Michal Kvet
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Michal Kvet

Michal Kvet is a researcher, educator, and database expert at the University of Žilina in Slovakia. His primary focus areas are databases, analytics, performance, and cloud computing. He works closely with Oracle and Oracle Academy. He is the co-author of multiple textbooks (a SQL and PL/SQL cookbook, a book on APEX application development, a book on temporal databases, and a MySQL cookbook), coordinates multiple Erasmus+ projects and co-organizes several research conferences and database workshops. Besides this, he supervises engineering projects and bachelor's, master's, and doctoral theses. Over the years, his research has been associated with date and time management and temporal databases. He has Oracle's SQL, PL/SQL, Cloud, Analytics, and Administration certifications. His core knowledge of temporality is provided to you in this book.
Read more about Michal Kvet

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Deploying duration models using timepoint borders

Although using timepoints in the system makes it possible to model the elapsed time duration, border identification can be demanding and too time-consuming; therefore, it is necessary to find the direct next state. The processing takes place in two phases. Firstly, the states where the validity begins after a defined timepoint (T) are identified, then the state with the lowest value of the beginning of validity is selected from this set. OBJ_REF expresses the referenced object identifier:

  • First phase:
    SELECT Tab.*, RANK() OVER(ORDER BY BD) as rank
     FROM Tab
      WHERE BD>T and ID=OBJ_REF;
  • Second phase:
    SELECT *
     FROM
       (SELECT Tab.*, RANK() OVER(ORDER BY BD) as rank
         FROM Tab
          WHERE BD>T and ID=OBJ_REF
        )
      WHERE rank=1;

Note that a solution where only the end date of the validity (state expiration...

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Developing Robust Date and Time Oriented Applications in Oracle Cloud
Published in: May 2023Publisher: PacktISBN-13: 9781804611869

Author (1)

author image
Michal Kvet

Michal Kvet is a researcher, educator, and database expert at the University of Žilina in Slovakia. His primary focus areas are databases, analytics, performance, and cloud computing. He works closely with Oracle and Oracle Academy. He is the co-author of multiple textbooks (a SQL and PL/SQL cookbook, a book on APEX application development, a book on temporal databases, and a MySQL cookbook), coordinates multiple Erasmus+ projects and co-organizes several research conferences and database workshops. Besides this, he supervises engineering projects and bachelor's, master's, and doctoral theses. Over the years, his research has been associated with date and time management and temporal databases. He has Oracle's SQL, PL/SQL, Cloud, Analytics, and Administration certifications. His core knowledge of temporality is provided to you in this book.
Read more about Michal Kvet