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From GitBox <...@apache.org>
Subject [GitHub] keith-turner commented on a change in pull request #38: Continue tour
Date Thu, 01 Jan 1970 00:00:00 GMT
keith-turner commented on a change in pull request #38: Continue tour
URL: https://github.com/apache/accumulo-website/pull/38#discussion_r150927221
 
 

 ##########
 File path: tour/ranges-splits.md
 ##########
 @@ -0,0 +1,36 @@
+---
+title: Ranges and Splits
+---
+
+A Range is a specified group of Keys. There are many different ways to create a Range.  Here
are a few examples:
+```java
+new Range(Key startKey, Key endKey)  // Creates a range from startKey inclusive to endKey
inclusive.
+new Range(CharSequence row)  // Creates a range that covers an entire row.
+new Range(CharSequence startRow, CharSequence endRow) // Creates a range from startRow inclusive
to endRow inclusive.
+```
+
+A Scanner by default will scan all Keys in a table but this can be inefficient. It is a good
practice to set a range on a Scanner.
+```java
+scanner.setRange(new Range("id0000", "id0010"));  // returns rows from id0000 to id0010
+```
+
+As your data grows larger, Accumulo will split tables across multiple servers called Tablet
Servers.  
+By default a table will get split on row boundaries, guaranteeing an entire row to be on
one Tablet Server.  We have the ability to 
+tell Accumulo were to split tables by setting split points. This is done using _addSplits_
in the [TableOperations] API.  The image below 
+demonstrates how Accumulo splits data.  
 
 Review comment:
   Should mention Tablets in this paragraph.

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