jmark99 commented on code in PR #330:
URL: https://github.com/apache/accumulo-website/pull/330#discussion_r927693084
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tour-jshell/basic-read-write2.md:
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+---
+title: Writing and Reading
+---
+
+Accumulo is a big key/value store. Writing data to Accumulo is flexible and
fast. Like any
+database, Accumulo stores data in tables and rows. Each row in an Accumulo
table can hold many
+key/value pairs.
+
+Our next exercise shows how to write and read from a table.
+
+Let's create a table called "GothamPD".
+
+At the JShell prompt, enter the following:
+```commandline
+jshell> client.tableOperations().create("GothamPD");
+```
+
+Accumulo uses Mutation objects to hold all changes to a row in a table. Each
row has a unique row
+ID.
+
+```commandline
+jshell> Mutation mutation1 = new Mutation("id0001");
+mutation1 ==> org.apache.accumulo.core.data.Mutation@1
+```
+
+Create key/value pairs for Batman. Put them in the "hero" family.
+```commandline
+jshell> mutation1.put("hero","alias", "Batman");
+jshell> mutation1.put("hero","name", "Bruce Wayne");
+jshell> mutation1.put("hero","wearsCape?", "true");
+```
+
+Create a BatchWriter to the GothamPD table and add your mutation to it.
Try-with-resources will
+close for us.
+
+```commandline
+jshell> try (BatchWriter writer = client.createBatchWriter("GothamPD")) {
+ ...> writer.addMutation(mutation1);
+ ...> }
+```
+Read and print all rows of the "GothamPD" table.
+
+Note that within the JShell environment, references to Scanner are ambiguous
since it matches both
+interface ```org.apache.accumulo.core.client.Scanner``` and class
```java.util.Scanner```. This can
+be resolved by either using the fully qualified name for the Scanner, or more
easily, by using the
+base class, ```ScannerBase```, in place of ```Scanner``` (this should
generally only be required when
+within the JShell environment).
+
+```commandline
+jshell> try (ScannerBase scan = client.createScanner("GothamPD",
Authorizations.EMPTY)) {
+ ...> System.out.println("Gotham Police Department Persons of Interest:");
+ ...> for(Map.Entry<Key, Value> entry : scan) {
+ ...> System.out.printf("Key : %-50s Value : %s\n", entry.getKey(),
entry.getValue());
+ ...> }
+ ...> }
+Gotham Police Department Persons of Interest:
+Key : id0001 hero:alias [] 1654274195071 false Value : Batman
+Key : id0001 hero:name [] 1654274195071 false Value : Bruce Wayne
+Key : id0001 hero:wearsCape? [] 1654274195071 false Value : true
+```
+
+Be aware the timestamps will differ for you.
+
+Good job! That is all it takes to write and read from Accumulo.
+
+Notice a lot of other information was printed from the Keys we created.
Accumulo is flexible
+because hidden within its [Key] is a rich data model that can be broken up
into different parts. We
+will cover the [Data Model][dmodel] in the next lesson.
+
+### But wait... I thought Accumulo was all about Security?
+
+Spoiler Alert: It is! Did you notice the `Authorizations.EMPTY` we passed in
when creating a
+[Scanner]? The data we created in this first lesson was not secured with
Authorizations so the
+Scanner didn't require any Authorizations to read it. More to come later in
the [Authorizations][auths]
+lesson!
+
+[dmodel]: /tour-jshell/data-model2
+[auths]: /tour-jshell/authorizations2
Review Comment:
I tried the changes and it would not work on my local web server. Compared
these links to similar existing tour pages and then format is the same. Will
keep an eye on this once it is published and update then if necessary.
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