RESTORE_FLEXTABLE_DEFAULT_KEYS_TABLE_AND_VIEW
恢复键表和视图。无论删除任一表,函数还会将键表与其关联的 Flex 表链接起来。该函数还会指示其恢复了一个对象还是同时恢复了两个对象。
这是元函数。您必须在顶级 SELECT 语句中调用元函数。
行为类型
易变语法
RESTORE_FLEXTABLE_DEFAULT_KEYS_TABLE_AND_VIEW ('flex-table')
参数
-
flex-table
- Flex 表的名称
示例
此示例显示如何使用现有的 Flex 表调用此函数,还原键表和视图:
=> SELECT RESTORE_FLEXTABLE_DEFAULT_KEYS_TABLE_AND_VIEW('darkdata');
RESTORE_FLEXTABLE_DEFAULT_KEYS_TABLE_AND_VIEW
----------------------------------------------------------------------------------
The keys table public.darkdata_keys was restored successfully.
The view public.darkdata_view was restored successfully.
(1 row)
此示例描述函数恢复了 darkdata_view
,但不需要恢复 darkdata_keys
:
=> SELECT RESTORE_FLEXTABLE_DEFAULT_KEYS_TABLE_AND_VIEW('darkdata');
RESTORE_FLEXTABLE_DEFAULT_KEYS_TABLE_AND_VIEW
------------------------------------------------------------------------------------
The keys table public.darkdata_keys already exists and is linked to darkdata.
The view public.darkdata_view was restored successfully.
(1 row)
还原键表之后,其中没有任何内容。要填充 Flex 键,请调用 COMPUTE_FLEXTABLE_KEYS 函数。
=> SELECT * FROM darkdata_keys;
key_name | frequency | data_type_guess
----------+-----------+-----------------
(0 rows)