This topic describes the new commands that are supported by performance-enhanced instances of ApsaraDB for Redis Enhanced Edition (Tair). Performance-enhanced instances inherit specific features of Tair and support the commands supported by Community Edition as well as some new commands. This helps you simplify the development process and improve data processing efficiency.

Supported new command types

Table 1. Supported new command types
Command type Description
CAS and CAD commands These commands are developed to enhance the performance of Redis strings. You can use them to implement simple and efficient distributed locks.
TairString commands A TairString is a string that contains a version number. TairStrings contain keys, values, and version numbers. The INCRBY and INCRBYFLOAT commands are used to increase or decrease the values of Redis strings. You can use TairStrings to limit the range of results returned by these commands. If a result is out of range, an error message is returned.
TairHash commands A TairHash is a hash that supports multiple commands and provides the same high performance as a Redis-native hash. In addition, TairHashes allow you to specify the expiration time and version number of a field. This helps you simplify the development process. TairHashes use the efficient active expire algorithm to check the expiration time of fields and delete expired fields. This process does not increase the database response time.
TairGIS commands A TairGIS is a data structure that uses R-tree indexes and supports geographic information system (GIS) API operations. Redis-native GEO commands allow you to use one-dimensional indexes to query points. TairGIS commands allow you to query points, lines, and planes by using two-dimensional indexes. You can also use TairGIS commands to check the relationships between different elements, such as whether A contains B or A intersects with B.
TairBloom commands A TairBloom is a Bloom filter that supports dynamic scaling and is compatible with RedisBloom commands. Compared with traditional methods that achieve a similar feature, TairBlooms consume less memory and maintain a stable false positive rate during scaling. You can use TairBlooms to check whether a large amount of data exists. In this case, a specific false positive rate is allowed.
TairDoc commands A TairDoc is a document data structure. It supports JSON standards and is compatible with RedisJSON commands. TairDoc data is stored in binary trees and allows for fast access to child elements.

Other commands

In addition to the preceding commands, performance-enhanced instances of ApsaraDB for Redis Enhanced Edition (Tair) also support the commands that are supported by Community Edition. For more information, see Commands supported by Community Edition.