Aggregating Datasources (ADS), first introduced with BIOVIA Isentris, merge the record sets of queries against at least two separate Integrating Datasources (IDS) into a single, combined record set. This is similar to what the UNION operator in standard SQL does. As separate IDS can point to different databases and even different database systems (Oracle, SQL Server) this is a nice feature for workflows where the merging of query results from different datasources in a single query is difficult to achieve with the databases' standard features. BIOVIA Insight and the Pipeline Pilot Datasource Builder support the use and creation of ADS. 

When considering the use of ADS' please be aware that this is a performance-sensitive feature - the BIOVIA Queryservice must fetch and consolidate the data from the different queries so that typical database performance switches like Oracle's FIRST ROWS hint may be less effective or inactive.