¶ Description
Performs an in-memory left join or inner join between two tables. Unlike some other join operations, the tables do not need to be sorted beforehand. This action is suitable when the slave table may contain duplicate keys.
¶ Parameters
Parameters:
-
Join mode:
Select the join strategy. Options includeleft outer(default) orinner join. -
Master key in master table A on 1st pin (0):
The column from the master table (connected to input pin 0) used as the join key. -
Column name prefix for master table A:
Optional prefix for all columns coming from the master table. -
Slave key in table B on 2nd pin (1):
The column from the slave table (connected to input pin 1) used as the join key. -
Column name prefix for slave table B:
Optional prefix for all columns coming from the slave table.
¶ About
The InMemoryJoin action executes a join fully in memory for high-speed processing. It is similar to the MultiJoin action but with key differences:
- The input tables do not need to be sorted.
- The slave table can contain duplicate keys, allowing many-to-one or many-to-many joins.
- Because the join occurs entirely in RAM, the action is recommended for small to medium datasets.
Note: For larger datasets, where RAM consumption might be a concern, consider using MultiJoin with memory-efficient configuration.
