CREATE SEQUENCE serial START 10;创建

drop SEQUENCE serial；删除

SELECT nextval(‘serial‘);查询

def getmoseries():
    while True:
        try:
            cursor = db.session.execute("SELECT nextval(‘serial‘)")
            mo = cursor.fetchall()[0][0]
            print(f"---{mo}")
            if mo > 99998:
                db.session.execute("drop SEQUENCE serial")
                continue
            break
        except:
            db.session.rollback()
            db.session.execute("CREATE SEQUENCE serial START 1")
            continue
    return mo
#备注：如果不存在序列，你查询就会报错，数据库报错就不会执行下一条语句，你需要回滚