Differences Between Hybrid DPS and Extreme DPS
As two types of compute engines offered by Relyt, Hybrid DPS and Extreme DPS have many differences concerning performance, support for SQL commands, support for functions, and some other factors.
This topic records the differences between Hybrid DPS and Extreme DPS in support for SQL commands and functions for your quick reference.
Differences in support for SQL commands
Hybrid DPS and Extreme DPS have some differences in support for SQL commands. Therefore, as instances of these two types of compute engines, there are many different differences between Hybrid DPS clusters and Extreme DPS clusters.
Queries that include the following database objects cannot be run on Extreme DPS clusters:
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Functions created by CREATE FUNCTION
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Procedures created by CREATE PROCEDURE
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Cursors declared by DECLARE
Differences in support for functions
The following table lists the differences between the functions that Hybrid DPS and Extreme DPS both support.
| Function | Hybrid DPS | Extreme DPS |
|---|---|---|
|| | || produces null if any of the strings to concatenate is null. For example, 'a' || null -> null. | || ignores the null ones. For example, 'a' || null -> 'a'. |
CONCAT_WS | The strings to concatenate can be any supported data type. | The strings to concatenate can only be text type. |
The following table lists the functions supported only by Extreme DPS.
| Function | Description |
|---|---|
| DATEDIFF | Returns the difference between the date parts of two date or timestamp expressions. |