发表日期： 2022-11-30 15:19:08 浏览次数：401
舟山企业建站
币安推出的交易所平台币模式首次让用户参与到平台建设当中，享受平台发展的红利。据悉，币安将平台当季净利润的20%用于BNB回购，通过市场交易行为兑现平台的预期价值，以维持平台币价稳步上涨。这一做法类似于证券市场中以现金流作抵押发行债券，后期再通过利润等方式回购的模式。
随后，火币、OKCoin等各大平台也纷纷推出平台币，在BNB的基础上增加了更多权益，交易所的竞争逐渐演变为平台币、甚至平台生态的竞争。
ALTER FOREIGN TABLE — 更改一个外部表的定义
ALTER FOREIGN TABLE [ IF EXISTS ] [ ONLY ] name [ * ] action [, ... ]
ALTER FOREIGN TABLE [ IF EXISTS ] [ ONLY ] name [ * ]
RENAME [ COLUMN ] column_name TO new_column_nameALTER FOREIGN TABLE [ IF EXISTS ] name
RENAME TO new_nameALTER FOREIGN TABLE [ IF EXISTS ] name
SET SCHEMA new_schema其中 action 是以下之一：
ADD [ COLUMN ] column_name data_type [ COLLATE collation ] [ column_constraint [ ... ] ]
DROP [ COLUMN ] [ IF EXISTS ] column_name [ RESTRICT | CASCADE ]
ALTER [ COLUMN ] column_name [ SET DATA ] TYPE data_type [ COLLATE collation ]
ALTER [ COLUMN ] column_name SET DEFAULT expression
ALTER [ COLUMN ] column_name DROP DEFAULT
ALTER [ COLUMN ] column_name { SET | DROP } NOT NULL
ALTER [ COLUMN ] column_name SET STATISTICS integer
ALTER [ COLUMN ] column_name SET ( attribute_option = value [, ... ] )
ALTER [ COLUMN ] column_name RESET ( attribute_option [, ... ] )
ALTER [ COLUMN ] column_name SET STORAGE { PLAIN | EXTERNAL | EXTENDED | MAIN }
ALTER [ COLUMN ] column_name OPTIONS ( [ ADD | SET | DROP ] option ['value'] [, ... ])
ADD table_constraint [ NOT VALID ]
VALIDATE CONSTRAINT constraint_name
DROP CONSTRAINT [ IF EXISTS ] constraint_name [ RESTRICT | CASCADE ]
DISABLE TRIGGER [ trigger_name | ALL | USER ]
ENABLE TRIGGER [ trigger_name | ALL | USER ]
ENABLE REPLICA TRIGGER trigger_name
ENABLE ALWAYS TRIGGER trigger_name
SET WITH OIDS
SET WITHOUT OIDS
INHERIT parent_table
NO INHERIT parent_table
OWNER TO { new_owner | CURRENT_USER | SESSION_USER }
OPTIONS ( [ ADD | SET | DROP ] option ['value'] [, ... ])ALTER FOREIGN TABLE更改一个现有外部表的定义。 有几种子形式：
ADD COLUMN
这种形式使用与CREATE FOREIGN TABLE相同的语法把 一个新的列增加到该外部表。和为常规表增加一列不同，这种形式并不影响底层 的存储：这个动作只是简单地声明通过该外部表可以访问某个新的列而已。
