GBYTYPE
Specifies which algorithm—GROUPBY HASH or GROUPBY PIPELINED —the Vertica query optimizer should use to implement a GROUP BY clause.
Specifies which algorithm—GROUPBY HASH or GROUPBY PIPELINED —the Vertica query optimizer should use to implement a GROUP BY clause. If both algorithms are valid for this query, the query optimizer chooses the specified algorithm over the algorithm that the query optimizer might otherwise choose in its query plan.
Syntax
GROUP BY /*+GBYTYPE( HASH | PIPE )*/
Arguments
HASH | PIPE- Specifies the GROUP BY algorithm to use:
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HASH: GROUPBY HASH algorithm -
PIPE: GROUPBY PIPELINED algorithmNote
Vertica uses the GROUPBY PIPELINED algorithm only if the query and one of its projections comply with GROUPBY PIPELINED requirements. Otherwise, Vertica issues a warning and uses GROUPBY HASH.
For more information about both algorithms, see GROUP BY implementation options.
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