sql - How small should a table using Diststyle ALL be in Amazon Redshift? -

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how small should table using diststyle in amazon redshift?

it says here: http://dwbitechguru.blogspot.com/2014/11/performance-tuning-in-amazon-redshift.html vey small tables, redshift should use diststyle instead of or key. how small small? if specify row number in clause of query: select relname, reldiststyle pg_class how many rows should specify?

it depends on cluster size using. diststyle copy data of table nodes - mitigate data transfer requirement across nodes. can find out size of table , redshift nodes available size, if can afford copy table multiple times per node, it!

also, if have requirement of joining other tables table very frequently, in 70% of queries, believe worth space if want better query performance.

if join keys across tables same in terms of cardinality, can afford distribute tables on key similar keys lie in same node obviate replication of data.

i suggest trying out 2 options above, , comparing average query run times of around 10 queries , come decision.


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