본문 바로가기
RDBMS/Oracle

Hierarchical Queries 계층 구조 쿼리들

by 이도현 2021. 11. 29.

https://docs.oracle.com/en/database/oracle/oracle-database/21/sqlrf/Hierarchical-Queries.html

 

SQL Language Reference

 

docs.oracle.com

https://docs.oracle.com/cd/B19306_01/server.102/b14200/queries003.htm

 

Hierarchical Queries

Hierarchical Queries If a table contains hierarchical data, then you can select rows in a hierarchical order using the hierarchical query clause: hierarchical_query_clause::= Description of the illustration hierarchical_query_clause.gif START WITH specifie

docs.oracle.com

https://docs.oracle.com/database/121/SQLRF/queries003.htm#SQLRF52332

 

Hierarchical Queries

Hierarchical Queries If a table contains hierarchical data, then you can select rows in a hierarchical order using the hierarchical query clause: hierarchical_query_clause::= Description of the illustration ''hierarchical_query_clause.gif'' condition can b

docs.oracle.com

 

일반적 상황에서는 다음 쿼리를 바탕으로 사용할 수 있다.

SELECT last_name, employee_id, manager_id, LEVEL
      FROM employees
      START WITH employee_id = 100
      CONNECT BY PRIOR employee_id = manager_id
      ORDER SIBLINGS BY last_name;