Storing Time Alone: Enhancing Performance and Space Efficiency
The need to store time as a separate entity, excluding the date component, arises in many database management scenarios. Whether to optimize performance or conserve disk space, this article explores various techniques to achieve this feat in Oracle.
Interval Day to Second: A Tailor-Made Solution?
The INTERVAL DAY TO SECOND data type emerges as a promising candidate for storing time-only values. Designed explicitly for this purpose, it offers a highly efficient and precise way to represent time durations. However, it does not provide any significant space savings, as the interval's representation requires a fixed size of 11 bytes.
Sample Code:
CREATE TABLE t1 (time_of_day INTERVAL DAY(0) TO SECOND(0)); INSERT INTO t1 VALUES (TO_DSINTERVAL('0 23:59:59')); SELECT DATE '2009-05-13' + time_of_day FROM t1;
Limitations:
While the INTERVAL DAY TO SECOND data type provides a clean and purpose-built solution, it may not be the most effective option for optimizing disk space. If storage efficiency is a primary concern, alternative approaches should be considered.
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