diff --git a/documentation/concept/sql-optimizer-hints.md b/documentation/concept/sql-optimizer-hints.md index 9005ab9d9..ffe3fe573 100644 --- a/documentation/concept/sql-optimizer-hints.md +++ b/documentation/concept/sql-optimizer-hints.md @@ -48,9 +48,9 @@ past from the row that matches by timestamp. For this, we need a more sophisticated algorithm. Our optimized algorithms assume the JOIN condition matches additional columns by -equality. Basically, we have a join key that must match on both sides. An even -narrower common case we optimize for is matching on a _symbol column_ on both -sides, but many optimizations work for other key combinations as well. +equality. Basically, there's a join key that must match on both sides. An even +narrower common case we optimize more aggressively for is matching on a _symbol +column_ on both sides. We distinguish these two cases: @@ -58,13 +58,13 @@ We distinguish these two cases: In this case, when scanning the right-hand table backward from the timestamp of the left-hand row, we find a match much sooner than reaching the timestamp of -the previous left-hand row. We end up scanning only a small subset of right-hand -rows. In the diagram, we show the scanned portions of the right-hand dataset in -red. +the previous left-hand row. We end up scanning only a small subset of the +right-hand rows. In the diagram, we show the scanned portions of the right-hand +dataset in red. -The best way to perform this join is to first locate the right-hand row that -matches by timestamp (marked with the dotted line), then scan backward to find -the row satisfying additional join conditions. +The best way to perform this join is the straightforward one: first locate the +right-hand row that matches by timestamp (marked with the dotted line), then +scan backward to find the row satisfying additional join conditions.