5 Easy Facts About DDL迁移/转换 Described

The storage facts construction of OceanBase is created depending on LSM-Tree, which has similarities for the strategy of LevelDB. The info modification is to start with recorded in MemTable (dynamic information in memory) applying linked checklist, and The top is linked to the corresponding block in block cache.

You wish to Handle the folks what A part of the house They can be permitted to accessibility and sort of obtain.

          Creates a whole new DDL object which can comprise statements to perform steps relating to the offered object.

OceanBase supports international crucial to constrain information regularity, which is an important edge as compared to all kinds of other distributed DBMS. Overseas key reference is outlined when making new desk schema.

Insert COLUMN is not really an in-position operation for saved columns (done devoid of utilizing a temporary desk) because the expression need to be evaluated by the server.

(three) Alternate Compaction: When one ObServer is going to compact a person partition, queries to the merged partition will be despatched to ObServers in other Zones storing replicas of a similar partition.

From the TPC-C benchmark examination, which is named the "World Cup" on the databases sector, OceanBase broke the entire world history, which was preserved by Oracle for nine consecutive several years, making Ant Fiscal the 1st Chinese enterprise to best the record ever.  

The storage facts framework of OceanBase is made depending on LSM-Tree, which has similarities towards the strategy of LevelDB. The info modification is initially recorded in MemTable (dynamic info in memory) utilizing connected record, and The pinnacle is connected to the corresponding block in block cache.

Through the minimal using表达式优化 peak time period during the night time or in the event the size of MemTable reaches the edge, OceanBase will merge the MemTable into SSTable(static information in disk) employing considered one of adhering to merge algorithms:

The LOCK clause may be utilized for operations which can be performed in position and is helpful for high-quality-tuning the degree of concurrent use of the desk in the course of operations.

When you make a desk with out a Major crucial, InnoDB chooses 1 系统函数适配/兼容 for you, which may be the primary UNIQUE vital described on NOT NULL columns, or simply a process-generated key.

TRUNCATE – take out all documents from a table; also, all spaces allocated for the records are taken off.

OceanBase uses column compression. It implements quite a few encoding algorithms Oracle转MySQL and it routinely chooses the best suited a single for every column. It adopts column compression to leverage facts similarity, such as very same details kind, same benefit selection, etcetera.

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