Dremio query forming

[vincent_mayer]

@balaji.ramaswamy

SELECT "part"."p_partkey" AS "p_partkey", "part"."p_name", "part"."p_mfgr" AS "p_mfgr", "part"."p_brand" AS "p_brand", "part"."p_type", "part"."p_size" AS "p_size", "part"."p_container" AS "p_container", "part"."p_retailprice" AS "p_retailprice", "part"."p_comment", "supplier"."s_suppkey", "supplier"."s_name", "supplier"."s_address" COLLATE "C" AS "s_address", "supplier"."s_nationkey", "supplier"."s_phone", "supplier"."s_acctbal", "supplier"."s_comment" COLLATE "C" AS "s_comment"
FROM (SELECT "part"."p_partkey", "part"."p_name" COLLATE "C" AS "p_name", "part"."p_mfgr", "part"."p_brand", "part"."p_type" COLLATE "C" AS "p_type", "part"."p_size", "part"."p_container", "part"."p_retailprice", "part"."p_comment" COLLATE "C" AS "p_comment"
FROM "public"."part"
WHERE "part"."p_size" = 15 AND "part"."p_type" COLLATE "C" LIKE '%BRASS' COLLATE "C") AS "part"
INNER JOIN "public"."supplier" ON TRUE

The query takes round about 2 min 20 sec

[balaji.ramaswamy]

@vincent_mayer Same query when push down from Dremio is taking 19 minutes, Dremio does not do anything but sends the above push down into the back end DB. This may indicate a network condition. If the push down was not good, even running the push down on the source, would have been slow

[vincent_mayer]

@balaji.ramaswamy
okay, thanks!

Can you still elaborate on this?

• What part of the system decides which data gets joined?
• And what criteria does the system use to pick the right join?

I am curious

[balaji.ramaswamy]

@vincent_mayer This will be based on planner rules like row count estimates, I see the query I pasted which is what is sent to the backend DB is taking 2 minutes to run. But when the same query is sent from Dremio it takes longer. Is it possible to install the client like if this is Postgres then psql on the Dremio executor and run the same SQL, we can narrow it down then