https://blog.youkuaiyun.com/XL_upzh-cnhttps://blog.youkuaiyun.com/https://blog.youkuaiyun.com/XL_up/article/details/133820361https://blog.youkuaiyun.com/XL_up/article/details/133820361XL_upSat, 14 Oct 2023 01:05:45 +0800https://blog.youkuaiyun.com/XL_up/article/details/133820325https://blog.youkuaiyun.com/XL_up/article/details/133820325XL_upSat, 14 Oct 2023 01:01:08 +0800https://blog.youkuaiyun.com/XL_up/article/details/133820316https://blog.youkuaiyun.com/XL_up/article/details/133820316XL_upSat, 14 Oct 2023 00:55:44 +0800https://blog.youkuaiyun.com/XL_up/article/details/133820277https://blog.youkuaiyun.com/XL_up/article/details/133820277XL_upSat, 14 Oct 2023 00:51:12 +0800https://blog.youkuaiyun.com/XL_up/article/details/133820266https://blog.youkuaiyun.com/XL_up/article/details/133820266XL_upSat, 14 Oct 2023 00:47:05 +0800fromlist字段指向这个空表（原先其值为NULL，是一个空指针），并且这个空表与刚刚添加的RTE结点是对应的。因为其并不与任何的实体关系表绑定，也不包含任何可以被引用的元组条目，是一张空表。函数的作用是，如果当前的查询结点（输入的查询结点）的jointree是空树，即结点的fromlist字段是一个空指针，那么替换其为将其指向一个RTE_RESULT类型的“假”关系表。]]>https://blog.youkuaiyun.com/XL_up/article/details/133820206https://blog.youkuaiyun.com/XL_up/article/details/133820206XL_upSat, 14 Oct 2023 00:43:12 +0800https://blog.youkuaiyun.com/XL_up/article/details/133820152https://blog.youkuaiyun.com/XL_up/article/details/133820152XL_upSat, 14 Oct 2023 00:36:02 +0800https://blog.youkuaiyun.com/XL_up/article/details/133820118https://blog.youkuaiyun.com/XL_up/article/details/133820118XL_upSat, 14 Oct 2023 00:30:01 +0800https://blog.youkuaiyun.com/XL_up/article/details/133820097https://blog.youkuaiyun.com/XL_up/article/details/133820097XL_upSat, 14 Oct 2023 00:26:21 +0800https://blog.youkuaiyun.com/XL_up/article/details/133820084https://blog.youkuaiyun.com/XL_up/article/details/133820084XL_upSat, 14 Oct 2023 00:23:47 +0800https://blog.youkuaiyun.com/XL_up/article/details/133820075https://blog.youkuaiyun.com/XL_up/article/details/133820075XL_upSat, 14 Oct 2023 00:21:36 +0800https://blog.youkuaiyun.com/XL_up/article/details/133820047https://blog.youkuaiyun.com/XL_up/article/details/133820047XL_upSat, 14 Oct 2023 00:19:21 +0800https://blog.youkuaiyun.com/XL_up/article/details/133819780https://blog.youkuaiyun.com/XL_up/article/details/133819780XL_upSat, 14 Oct 2023 00:14:16 +0800https://blog.youkuaiyun.com/XL_up/article/details/133819751https://blog.youkuaiyun.com/XL_up/article/details/133819751XL_upFri, 13 Oct 2023 23:40:01 +0800https://blog.youkuaiyun.com/XL_up/article/details/133819648https://blog.youkuaiyun.com/XL_up/article/details/133819648XL_upFri, 13 Oct 2023 23:32:10 +0800https://blog.youkuaiyun.com/XL_up/article/details/133819473https://blog.youkuaiyun.com/XL_up/article/details/133819473XL_upFri, 13 Oct 2023 23:10:10 +0800https://blog.youkuaiyun.com/XL_up/article/details/133819432https://blog.youkuaiyun.com/XL_up/article/details/133819432XL_upFri, 13 Oct 2023 23:01:32 +0800https://blog.youkuaiyun.com/XL_up/article/details/133819379https://blog.youkuaiyun.com/XL_up/article/details/133819379XL_upFri, 13 Oct 2023 22:56:38 +0800https://blog.youkuaiyun.com/XL_up/article/details/133819334https://blog.youkuaiyun.com/XL_up/article/details/133819334XL_upFri, 13 Oct 2023 22:49:54 +0800https://blog.youkuaiyun.com/XL_up/article/details/133819269https://blog.youkuaiyun.com/XL_up/article/details/133819269XL_upFri, 13 Oct 2023 22:42:21 +0800