Hierarchical SQL Queries: Databases for Developers #16
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6 سال پیش
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Often data contains a parent-child
Often data contains a parent-child relationship between rows in the same table. For example, company org charts and family trees.
You can use the power of SQL to traverse these hierarchical relationships. There are two ways to do this in Oracle Database:
- Connect By
- Recursive With
Watch this video to learn about data trees and find out how these work!
Further reading:
Hierarchical queries in the docs: docs.oracle.com/en/database/oracle/oracle-database…
Recursive subquery factoring in 11.2: oracle-base.com/articles/11g/recursive-subquery-fa…
Take the course! devgym.oracle.com/pls/apex/dg/class/databases-for-…
Need help with SQL? Ask us over on AskTOM: asktom.oracle.com/
Twitter: twitter.com/ChrisRSaxon
Daily SQL Twitter tips: twitter.com/SQLDaily
All Things SQL blog: blogs.oracle.com/sql/
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The Magic of SQL with Chris Saxon
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6 سال پیش
در تاریخ 1397/04/02 منتشر شده
است.
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