fix: minor change to kafka examples #104

Signed-off-by: Bohan Zhang <[email protected]>

integrations/sources/kafka.mdx

@@ -93,6 +93,19 @@ When creating a source in RisingWave, you can specify the following Kafka parame
 | receive.message.max.bytes             | properties.receive.message.max.bytes             | int     |
 | ssl.endpoint.identification.algorithm | properties.ssl.endpoint.identification.algorithm | str     |
 
+The additional Kafka parameters `queued.min.messages` and `queued.max.messages.kbytes` are specified with `properties.queued.min.messages` and `properties.queued.max.messages.kbytes`, respectively, when creating the source.
+
+```sql
+CREATE SOURCE s1 (v1 int, v2 varchar) with (
+  connector = 'kafka',
+  topic = 'kafka_1_partition_topic',
+  properties.bootstrap.server = 'message_queue:29092',
+  scan.startup.mode = 'earliest',
+  properties.queued.min.messages = 10000,
+  properties.queued.max.messages.kbytes = 65536
+) FORMAT PLAIN ENCODE JSON;
+```
+
 <Note>
 Set `properties.ssl.endpoint.identification.algorithm` to `none` to bypass the verification of CA certificates and resolve SSL handshake failure. This parameter can be set to either `https` or `none`. By default, it is `https`.
 </Note>
@@ -121,20 +134,26 @@ WITH (
    scan.startup.timestamp.millis='140000000'
 ) FORMAT PLAIN ENCODE AVRO (
    message = 'message_name',
-   schema.registry = 'http://127.0.0.1:8081'
+   schema.registry = 'http://127.0.0.1:8081',
+   schema.registry.username='your_schema_registry_username',
+   schema.registry.password='your_schema_registry_password'
 );
 ```
 
  </Tab>
   <Tab title="Upsert Avro">
 ```sql
-CREATE TABLE IF NOT EXISTS source_abc
+CREATE TABLE IF NOT EXISTS source_abc (
+  primary key (rw_key)
+)
+include key as rw_key
 WITH (
    connector='kafka',
    properties.bootstrap.server='localhost:9092',
    topic='test_topic'
 )
 FORMAT UPSERT ENCODE AVRO (
+   message = 'message_name',
    schema.registry = 'http://127.0.0.1:8081',
    schema.registry.username='your_schema_registry_username',
    schema.registry.password='your_schema_registry_password'
@@ -167,27 +186,16 @@ WITH (
     properties.bootstrap.server = 'message_queue:29092',
     scan.startup.mode = 'earliest'
 ) FORMAT PLAIN ENCODE JSON;
-```
-
-The additional Kafka parameters `queued.min.messages` and `queued.max.messages.kbytes` are specified with `properties.queued.min.messages` and `properties.queued.max.messages.kbytes`, respectively, when creating the source.
-
-```sql
-CREATE SOURCE s1 (v1 int, v2 varchar) with (
-  connector = 'kafka',
-  topic = 'kafka_1_partition_topic',
-  properties.bootstrap.server = 'message_queue:29092',
-  scan.startup.mode = 'earliest',
-  properties.queued.min.messages = 10000,
-  properties.queued.max.messages.kbytes = 65536
-) FORMAT PLAIN ENCODE JSON;
 ```
   </Tab>
   <Tab title="Upsert JSON">
 ```sql
 CREATE TABLE IF NOT EXISTS source_abc (
    column1 varchar,
    column2 integer,
+   primary key (rw_key)
 )
+include key as rw_key
 WITH (
    connector='kafka',
    properties.bootstrap.server='localhost:9092',