带有两个标识符的Oracle条件索引

Question

是否可以在两列上创建条件索引？

CREATE UNIQUE INDEX idx_dup_wfc
    ON WF_WORKFLOW_CLASS (CASE WHEN is_active = 1
      THEN (NAME, DEPT_OWNER)
         ELSE NULL
      END)

ORA-00906: missing left parenthesis然而,返回以下工作

CREATE UNIQUE INDEX idx_dup_wfc
    ON WF_WORKFLOW_CLASS (CASE WHEN is_active = 1
      THEN NAME
         ELSE NULL
      END)

Answer 1

是的,但您必须按列执行CASE:

CREATE UNIQUE INDEX idx_dup_wfc
    ON WF_WORKFLOW_CLASS 
     (CASE WHEN is_active = 1 THEN NAME END
     ,CASE WHEN is_active = 1 THEN DEPT_OWNER END
     )

(代码中的ELSE是多余的).