March 2021
Intermediate to advanced
265 pages
6h 50m
Chinese
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122
｜
第
8
章
在每个连接器中，
Information Schema
都有
8
个视图。对于某些不支持的功能（例如角色）
的连接器，查询对应的
InformationSchema
可能会产生一个不支持的错误：
SHOW TABLES IN system.information_schema;
Table
------------------
applicable_roles
columns
enabled_roles
roles
schemata
table_privileges
tables
views
(8 rows)
注意，在你通过
Information Schema
查询
schema
中的表时，也会返回
Information Schema
自身拥有的表：
SELECT * FROM hive.information_schema.tables;
table_catalog | table_schema | table_name | table_type
---------------+--------------------+------------------+----------
hive | web | nation | BASE TABLE
hive | information_schema | enabled_roles | BASE TABLE
hive | information_schema | roles | BASE TABLE