23 lines
892 B
Markdown
23 lines
892 B
Markdown
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# Query DAG
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The query is represented as a DAG, where each node represents an operation to be performed.
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There may be multiple roots to the DAG where each root represents a source of data.
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Root nodes will specify whether they are selecting data from the database or consuming data as a stream.
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The leaves of the DAG represent the results of the operation.
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A result node may be added as a child to any node to make that intermediate representation a finalized result.
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## Specification
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A query DAG consists of a set of nodes and a set of edges that form a directed acyclic graph (DAG).
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Each node has the following properties:
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* ID - A unique identifier for the node within the graph.
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* Kind - The kind of operation the node performs.
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* Spec - The spec, specifies the parameters provided to the node detailing the specifics of the operation.
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The parameters vary by the kind of node.
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