Add a query hint to limit the number of concurrent source queries
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Key: TEIID-2356
URL:
https://issues.jboss.org/browse/TEIID-2356
Project: Teiid
Issue Type: Sub-task
Components: Query Engine
Affects Versions: 7.4
Reporter: Steven Hawkins
Assignee: Steven Hawkins
Priority: Minor
We would like a new query hint to limit the number of parallel executions of union
members. This is useful in two situations:
1. When the queries are expensive, but the overall union contains a limit that is most
likely to be fulfilled by the first member of the union
2. When the queries are backed by a common resource which may be overloaded by multiple
queries
The addition of a hint would make this manageable by the client; perhaps something like
"/*+ parallel=2*/"?