标记列为未使用 (Marking Columns Unused)
Posted by dbtan on 12月 16th, 2016Marking Columns Unused 基本操作步骤
1. 标记列为未使用 SQL ALTER TABLE <table_name> SET UNUSED (<column_name>);
2. 然后在数据库空闲时,再删除列 SQL ALTER TABLE <table_name> DROP UNUSED COLUMNS CHECKPOINT <n>; -- CHECKPOINT <n>
In the ALTER TABLE statement that fo
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