树状结构的节点深度计算的sql

前提有一张组织表.

CREATE TABLE organization_

(

organizationid bigint NOT NULL,

companyid bigint,

parentorganizationid bigint,

leftorganizationid bigint,

rightorganizationid bigint,

"name" character varying(100),

type_ character varying(75),

recursable boolean,

regionid bigint,

countryid bigint,

statusid integer,

comments text,

CONSTRAINT organization__pkey PRIMARY KEY (organizationid)

)

节点深度计算的sql:

SELECT MAX(level) AS height

FROM (SELECT Children.organizationid , COUNT(Parents.organizationid) AS level

FROM organization_ Parents, organization_ Children

WHERE Children.leftorganizationid BETWEEN Parents.leftorganizationid AND Parents.rightorganizationid

GROUP BY Children.organizationid) TMP;

结果例子:

3