Not known Factual Statements About 数据库国产化迁移

The storage data structure of OceanBase is designed dependant on LSM-Tree, which has similarities to your strategy of LevelDB. The information modification is to start with recorded in MemTable (dynamic facts in memory) employing connected listing, and The top is linked to the corresponding block in block cache.

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

From the standpoint of source administration, Each individual database occasion is considered as a tenant in OceanBase. Each and every tenant is allocated by using a unit pool that contains models. Every single unit is a gaggle of computation and storage resource on ObServers. Each and every tenant has at most one particular unit on 1 ObServer.

In order to avoid uncertainty plus the probable Area need For an additional concealed column, specify the PRIMARY Essential clause as A part of the Generate TABLE statement.

ADD COLUMN is not an in-position Procedure for saved columns (finished devoid of employing A brief desk) because the expression need to be evaluated from the server.

@TomJMuthirenthi I don't think DESCRIBE fits into any of the two. It just returns It can be own representation of how a Desk/DB is structured. You are able to accomplish exactly the same thing with e.g. Produce although not as "human-readable"

OceanBase uses column compression. It implements numerous encoding algorithms and it mechanically chooses the most fitted 1 for each column. It adopts column compression to leverage information similarity, such as same information form, exact same benefit selection, and many others.

The storage information composition of OceanBase is created based on LSM-Tree, which is similar for the technique of LevelDB. The data modification is very first recorded in MemTable (dynamic details in memory) using joined record, and The top is linked to the corresponding block in block cache.

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OceanBase works by using physiological logging to information many of the modification. Physiological targets about the modification on each single web site with no specifying the detailed data Firm inside the website page. OceanBase uses Paxos consensus algorithm to synchronize log replicas on distinctive server nodes.

(three) Alternate Compaction: When just one ObServer is going to compact just one partition, queries over the merged partition is going to be sent to ObServers in other Zones storing replicas of the exact same partition.

Within the point of view of source management, Each and every databases occasion is regarded as a tenant in OceanBase. Every single tenant is allotted that has a device pool containing units. Each and every unit is a group of computation and storage useful resource on ObServers. Just about every tenant has at most a person unit on a person ObServer.

Operate: A Dify plugin for connecting to and querying OceanBase databases. This job has become migrated to a whole new repository.

OceanBase implements block cache for Micro Block to speed using表达式优化 up large scan question. What's more, it implements a row cache for rows in block cache to accelerate compact get question.