Accelerators permit the joining of data from tables in different data sources to be stored in memory. This can greatly improve performance.

When joining data from Table 1 in Data Source 1 to data in Table 2 in Data Source 2, putting an accelerator on Table 2 causes Insight to read all of Table 2 into memory and use that to resolve the join to Table 1. This is useful when the number of records required from Table 2 is small enough to fit into memory.