Github user cloud-fan commented on a diff in the pull request:
https://github.com/apache/spark/pull/21252#discussion_r186345913
--- Diff:
sql/catalyst/src/main/scala/org/apache/spark/sql/internal/SQLConf.scala ---
@@ -1238,6 +1238,14 @@ object SQLConf {
.booleanConf
.createWithDefault(true)
+ val SORT_IN_MEM_FOR_LIMIT_THRESHOLD =
+ buildConf("spark.sql.limit.sortInMemThreshold")
+ .internal()
+ .doc("In sql like 'select x from t order by y limit m', if m is
under this threshold, " +
+ "sort in memory, otherwise do a global sort with disk.")
+ .intConf
+ .createWithDefault(2000)
--- End diff --
what if users only have a few queries which have large limit and they want
to disable the top n sort? I feel this config is more flexible than a boolean
flag.
---
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
