DOC-5112 added PHP hash search examples

Author: andy-stark-redis

content/develop/clients/php/queryjson.md

@@ -9,18 +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: 20
 ---
 
-This example shows how to index and query Redis JSON data using `predis`.
+This example shows how to create a
+[search index]({{< relref "/develop/interact/search-and-query/indexing" >}})
+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 Community Edition and `predis` installed, as described
-in the [Install](#install) section above.
+## 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
+[`Predis`]({{< relref "/develop/clients/php" >}}) client library if you
+haven't already done so.
+
+Add the following dependencies:
 
 ```php
 <?php
@@ -38,19 +47,9 @@ use Predis\Command\Argument\Search\SchemaFields\TagField;
 use Predis\Command\Argument\Search\SchemaFields\VectorField;
 ```
 
-Connect to the Redis server:
-
-```php
-$r = new PredisClient([
-                'scheme'   => 'tcp',
-                'host'     => '127.0.0.1',
-                'port'     => 6379,
-                'password' => '',
-                'database' => 0,
-            ]);
-```
+## Create data
 
-Create some test data to add to the database:
+Create some test data to add to your database:
 
 ```php
 $user1 = json_encode([
@@ -75,6 +74,23 @@ $user3 = json_encode([
 ], JSON_THROW_ON_ERROR);
 ```
 
+## 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/php/connect" >}})
+to learn more about the available connection options.
+
+```php
+$r = new PredisClient([
+                'scheme'   => 'tcp',
+                'host'     => '127.0.0.1',
+                'port'     => 6379,
+                'password' => '',
+                'database' => 0,
+            ]);
+```
+
 Create an
 [index]({{< relref "/develop/interact/search-and-query/indexing" >}}).
 In this example, only JSON documents with the key prefix `user:` are indexed.
@@ -99,6 +115,8 @@ catch (Exception $e) {
 }
 ```
 
+## 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
@@ -110,6 +128,8 @@ $r->jsonset('user:2', '$', $user2);
 $r->jsonset('user:3', '$', $user3);
 ```
 
+## 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
@@ -149,5 +169,76 @@ echo json_encode($res), PHP_EOL;
 // >>> [2,["city","London","count","1"],["city","Tel Aviv","count","2"]]
 ```
 
+## 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.
+
+```php
+$hashSchema = [
+    new TextField('name'),
+    new TagField('city'),
+    new NumericField('age'),
+];
+
+try {
+$r->ftCreate("hash-idx:users", $hashSchema,
+    (new CreateArguments())
+        ->on('HASH')
+        ->prefix(["huser:"]));
+}
+catch (Exception $e) {
+    echo $e->getMessage(), PHP_EOL;
+}
+```
+
+You use [`hmset()`]({{< relref "/commands/hset" >}}) to add the hash
+documents instead of [`jsonset()`]({{< relref "/commands/json.set" >}}).
+Supply the fields as an array directly, without using
+[`json_encode()`](https://www.php.net/manual/en/function.json-encode.php).
+
+```php
+$r->hmset('huser:1', [
+    'name' => 'Paul John',
+    'email' => '[email protected]',
+    'age' => 42,
+    'city' => 'London',
+]);
+
+$r->hmset('huser:2', [
+    'name' => 'Eden Zamir',
+    'email' => '[email protected]',
+    'age' => 29,
+    'city' => 'Tel Aviv',
+]);
+
+$r->hmset('huser:3', [
+    'name' => 'Paul Zamir',
+    'email' => '[email protected]',
+    'age' => 35,
+    'city' => 'Tel Aviv',
+]);
+```
+
+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
+almost the same except that the fields are returned directly in the
+result array rather than in a JSON string with `$` as its key:
+
+```php
+$res = $r->ftSearch("hash-idx:users", "Paul @age:[30 40]");
+echo json_encode($res), PHP_EOL;
+// >>> [1,"huser:3",["age","35","city","Tel Aviv","email","[email protected]","name","Paul Zamir"]]
+```
+
+## More information
+
 See the [Redis query engine]({{< relref "/develop/interact/search-and-query" >}}) docs
 for a full description of all query features with examples.