Storage Engine

The storage engine is the storage base of the database system. The database uses the storage engine to create, query, update and delete data. Depending on your needs, different storage engines will provide different storage mechanisms and can be combined with different execution engines to become database microkernels suitable for specific scenarios.

Currently, the YMatrix database system supports the use of several storage engines:

PostgreSQL-based HEAP
Greenplum-based AO (Append-optimized)
MARS2 developed by YMatrix

Storage Engine	Description
HEAP	The storage engine provided by PostgreSQL database, also known as heap tables, uses row storage. This type of table supports a large number of concurrent read and write, transaction, index and other features
AO	The storage engine provided by the Greenplum database, also known as append optimization table, uses Append-optimized (AO) storage format to load and read data in batches, and can provide performance advantages on HEAP tables. Append optimized storage provides checksums for data protection, compression, and row/column orientation. Tables with row or column addition optimization can be compressed
MARS2	The storage engine developed on MARS reduces the number of IO addressing times with its physically ordered merging method, thereby improving the query performance of data in the table. MARS2 supports compression, column storage, automatic archiving, pre-aggregation and other functions, and performs superiorly in timing scenarios. In terms of compression, MARS2 can provide customized compression solutions: *Coding chain (mxcustom)*. Enable coding chains to perform detailed, targeted and customized deep compression of the table. It refers in detail to a series of encoding algorithms developed by YMatrix, such as deltadelta, deltazigzag, etc.; targeted refers to the ability of encoding chains to be column-oriented, which is more refined and targeted than table-level compression; customization means that the encoding chain has the ability to combine compression, and you can further combine compression algorithms based on data types and general algorithms to achieve better compression effects. MARS2 tables currently do not support updates and deletion

Storage Engine Principle

Table Design Best Practices

Using compression

Storage Status Diagnosis