Function find_path

database_utils.py:249–294

(entity1,entity2,working_dir,level,depth=5)

    return res

def find_path(entity1,entity2,working_dir,level,depth=5):
    db = pymysql.connect(host='localhost',port=4321, user='root',
                      passwd='123',  charset='utf8mb4')
    db_name=os.path.basename(working_dir)
    cursor = db.cursor()

    query = f"""
        WITH RECURSIVE path_cte AS (
            SELECT 
                src_tgt,
                tgt_src,
                 CAST(CONCAT(src_tgt, '|', tgt_src) AS CHAR(5000)) AS path,
                1 AS depth
            FROM {db_name}.relations
            WHERE src_tgt = %s
              AND level = %s

            UNION ALL

            SELECT 
                p.src_tgt,
                t.tgt_src,
                CONCAT(p.path, '|', t.tgt_src),
                p.depth + 1
            FROM path_cte p
            JOIN {db_name}.relations t ON p.tgt_src = t.src_tgt
            WHERE NOT FIND_IN_SET(
                  CONVERT(t.tgt_src USING utf8mb4) COLLATE utf8mb4_unicode_ci,
                  CONVERT(p.path USING utf8mb4) COLLATE utf8mb4_unicode_ci
              )
              AND level = %s
              AND p.depth < %s
        )
        SELECT path
        FROM path_cte
        WHERE tgt_src = %s
        ORDER BY depth ASC
        LIMIT 1;
    """
    cursor.execute(query, (entity1,level,level,depth,entity2))
    result = cursor.fetchone()

    if result:
            return result[0].split('|')  # 返回节点列表
    else:
        return None

def search_nodes_link(entity1,entity2,working_dir,level=0):
    # cursor = db.cursor()