DOC-5108 added JavaScript hash search examples

Author: andy-stark-redis

content/develop/clients/nodejs/queryjson.md

@@ -9,20 +9,27 @@ categories:
 - oss
 - kubernetes
 - clients
-description: Learn how to use the Redis Query Engine with JSON
-linkTitle: Index and query JSON
-title: Example - Index and query JSON documents
+description: Learn how to use the Redis Query Engine with JSON and hash documents.
+linkTitle: Index and query documents
+title: Index and query documents
 weight: 2
 ---
 
 This example shows how to create a
 [search index]({{< relref "/develop/interact/search-and-query/indexing" >}})
-for [JSON]({{< relref "/develop/data-types/json" >}}) data and
-run queries against the index.
+for [JSON]({{< relref "/develop/data-types/json" >}}) documents and
+run queries against the index. It then goes on to show the slight differences
+in the equivalent code for [hash]({{< relref "/develop/data-types/hashes" >}})
+documents.
 
-Make sure that you have Redis Stack and `node-redis` installed. 
+## Initialize
 
-Start by importing dependencies:
+Make sure that you have [Redis Community Edition]({{< relref "/operate/oss_and_stack/" >}})
+or another Redis server available. Also install the
+[`node-redis`]({{< relref "/develop/clients/nodejs" >}}) client library if you
+haven't already done so.
+
+Add the following dependencies:
 
 ```js
 import {
@@ -33,14 +40,10 @@ import {
 } from 'redis';
 ```
 
-Connect to the database:
-
-```js
-const client = await createClient();
-await client.connect();
-```
+## Create data
 
-Create some test data to add to the database:
+Create some test data to add to your database. The example data shown
+below is compatible with both JSON and hash objects.
 
 ```js
 const user1 = {
@@ -65,6 +68,18 @@ const user3 = {
 };
 ```
 
+## Add the index
+
+Connect to your Redis database. The code below shows the most
+basic connection but see
+[Connect to the server]({{< relref "/develop/clients/nodejs/connect" >}})
+to learn more about the available connection options.
+
+```js
+const client = await createClient();
+await client.connect();
+```
+
 Create an index. In this example, only JSON documents with the key prefix `user:` are indexed. For more information, see [Query syntax]({{< relref "/develop/interact/search-and-query/query/" >}}).
 
 ```js
@@ -87,6 +102,8 @@ await client.ft.create('idx:users', {
 });
 ```
 
+## Add the data
+
 Add the three sets of user data to the database as
 [JSON]({{< relref "/develop/data-types/json" >}}) objects.
 If you use keys with the `user:` prefix then Redis will index the
@@ -103,6 +120,8 @@ const [user1Reply, user2Reply, user3Reply] = await Promise.all([
 ]);
 ```
 
+## Query the data
+
 You can now use the index to search the JSON objects. The
 [query]({{< relref "/develop/interact/search-and-query/query" >}})
 below searches for objects that have the text "Paul" in any field
@@ -161,6 +180,66 @@ Finally, close the connection to Redis.
 await client.quit();
 ```
 
+## Differences with hash documents
+
+Indexing for hash documents is very similar to JSON indexing but you
+need to specify some slightly different options.
+
+When you create the schema for a hash index, you don't need to
+add aliases for the fields, since you use the basic names to access
+the fields anyway. Also, you must use `HASH` for the `ON` option
+when you create the index. The code below shows these changes with
+a new index called `hash-idx:users`, which is otherwise the same as
+the `idx:users` index used for JSON documents in the previous examples.
+
+```js
+await client.ft.create('hash-idx:users', {
+    'name': {
+        type: SchemaFieldTypes.TEXT
+    },
+    'city': {
+        type: SchemaFieldTypes.TEXT
+    },
+    'age': {
+        type: SchemaFieldTypes.NUMERIC
+    }
+}, {
+    ON: 'HASH',
+    PREFIX: 'huser:'
+});
+```
+
+You use [`hSet()`]({{< relref "/commands/hset" >}}) to add the hash
+documents instead of [`json.set()`]({{< relref "/commands/json.set" >}}),
+but the same flat `userX` objects work equally well with either
+hash or JSON:
+
+```js
+const [huser1Reply, huser2Reply, huser3Reply] = await Promise.all([
+    client.hSet('huser:1', user1),
+    client.hSet('huser:2', user2),
+    client.hSet('huser:3', user3)
+]);
+```
+
+The query commands work the same here for hash as they do for JSON (but
+the name of the hash index is different). The format of the result is
+also the same:
+
+```js
+let findPaulHashResult = await client.ft.search(
+    'hash-idx:users', 'Paul @age:[30 40]'
+);
+
+console.log(findPaulHashResult.total); // >>> 1
+
+findPaulHashResult.documents.forEach(doc => {
+    console.log(`ID: ${doc.id}, name: ${doc.value.name}, age: ${doc.value.age}`);
+});
+// >>> ID: huser:3, name: Paul Zamir, age: 35
+```
+
+## More information
 
 See the [Redis Query Engine]({{< relref "/develop/interact/search-and-query" >}}) docs
 for a full description of all query features with examples.