From d0aa2c516579e32b3285427ccbd609fbcedafec1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E5=90=B4=E6=99=9F=20Wu=20Sheng?= <wu.sheng@foxmail.com>
Date: Sun, 11 Sep 2022 20:46:57 +0800
Subject: [PATCH] Add docs for virtual database tags (#307)

* Add docs for virtual database tags

* Update CHANGES.md
---
 CHANGES.md                                          |  3 ++-
 .../java-agent/Java-Plugin-Development-Guide.md     | 13 +++++++++++++
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/CHANGES.md b/CHANGES.md
index 46411e5ae..bcd3a46f2 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -15,7 +15,8 @@ Release Notes.
 #### Documentation
 
 * Update `configuration` doc about overriding default value as empty map/list accordingly.
-* Update plugin dev tags for cache relative tags
+* Update plugin dev tags for cache relative tags.
+* Add plugin dev docs for virtual database tags.
 
 All issues and pull requests are [here](https://github.com/apache/skywalking/milestone/150?closed=1)
 
diff --git a/docs/en/setup/service-agent/java-agent/Java-Plugin-Development-Guide.md b/docs/en/setup/service-agent/java-agent/Java-Plugin-Development-Guide.md
index 20e9ce65e..289a20efa 100644
--- a/docs/en/setup/service-agent/java-agent/Java-Plugin-Development-Guide.md
+++ b/docs/en/setup/service-agent/java-agent/Java-Plugin-Development-Guide.md
@@ -186,6 +186,19 @@ The value of `x-le` should be in JSON format. There are two options:
 }
 ```
 
+#### Vitural Database Relative Tags
+SkyWalking analysis Database(SQL-like) performance metrics through the following tags.
+
+```java
+    public static final StringTag DB_TYPE = new StringTag(3, "db.type");
+    public static final StringTag DB_STATEMENT = new StringTag(5, "db.statement");
+```
+
+* `db.type` records database type, such as sql, cassandra, Elasticsearch. 
+* `db.statement`records the sql statement of the database access.
+
+Read [backend's virtual database doc](https://skywalking.apache.org/docs/main/next/en/setup/service-agent/virtual-database/) for more details. 
+
 #### Vitural Cache Relative Tags
 Skywalking analysis cache performance related metrics through the following tags.