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Editor to share with you what are the data models in HBase, I believe most people do not know much about it, so share this article for your reference, I hope you can learn a lot after reading this article, let's go to know it!

HBase stores data as a table. The table consists of row and column families. The column is divided into several column families (row family), and the logical view is as follows:

Here are a few key concepts:

1) Row key (RowKey)

The row key is a byte array, and any string can be used as a row key.

The rows in the table are sorted by row keys, and the data is sorted and stored according to the byte order (byte order) of Row key

-- all access to the table is through row keys (single RowKey access, or RowKey scope access, or full table scan)

2) column families (ColumnFamily)

-- CF must be given when the table is defined

Each CF can have one or more column members (ColumnQualifier). Column members do not need to be given when the table is defined. New column family members can then be added dynamically as needed.

Data is stored separately according to CF. HBase's so-called column storage is stored separately according to CF (each CF corresponds to a Store). This design is very suitable for data analysis.

3) timestamp (TimeStamp)

There may be multiple versions of each Cell, which are distinguished by timestamps

4) Cell (Cell)

-- Cell is uniquely determined by row keys, column families: qualifiers, and timestamps

Data in Cell is typeless and is all stored in bytecode.

5) region (Region)

-- HBase automatically divides the table horizontally (according to Row) into multiple region, and each region saves a contiguous piece of data in a table.

At the beginning of each table, there is only one region. As the data is inserted into the table, the region increases continuously. When it reaches a threshold, the region will divide into two new region.

When there are more rows in the table, there will be more and more region. Such a complete table is saved on multiple Region.

HRegion is the smallest unit of distributed storage and load balancing in HBase. The smallest unit indicates that different HRegion can be distributed on different HRegionServer. However, a HRegion is not split into multiple server.

These are all the contents of the article "what are the data models in HBase?" Thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!

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