// Package sql define database sql statement
package sql

// RecursiveSQL define Topologic table recursive query statement
var RecursiveSQL = `WITH RECURSIVE recursive_tree as (
	SELECT uuid_from,uuid_to,page_id,flag
	FROM "Topologic"
	WHERE uuid_from is null and page_id = ?
	UNION ALL
	SELECT t.uuid_from,t.uuid_to,t.page_id,t.flag
	FROM "Topologic" t
	JOIN recursive_tree rt ON t.uuid_from = rt.uuid_to
	)
	SELECT * FROM recursive_tree;`

// TODO 为 Topologic 表增加唯一所以
// CREATE UNIQUE INDEX uuid_from_to_page_id_idx ON public."Topologic"(uuid_from,uuid_to,page_id);