14 lines
696 B
Markdown
14 lines
696 B
Markdown
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# Plan DAG
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The plan is represented as a DAG, where each node performs an operation and produces a result.
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The plan DAG is separate and distinct from the query DAG.
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The plan DAG specifies details about how the query will be executed, while the query DAG only specifies what the query is.
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There may be multiple roots to the DAG where each root represents a source of data.
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A root or source node may retrieve data from multiple different systems.
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Primarily data will be read from the storage interface, but may be streamed from the write ingest system or potentially external systems as well.
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The leaves of the DAG represent the results of the operation.
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The results are collected and returned.
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