From 78a41443e48af2f6342bc3dfefe37dfe8ee2f6cd Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E5=90=B4=E6=99=9F=20Wu=20Sheng?= <wu.sheng@foxmail.com>
Date: Mon, 4 Apr 2022 21:31:58 +0800
Subject: [PATCH] Add a doc for virtual database. (#8798)

---
 CHANGES.md                                      |  1 +
 docs/en/setup/service-agent/virtual-database.md | 15 +++++++++++++++
 docs/menu.yml                                   |  4 ++++
 3 files changed, 20 insertions(+)
 create mode 100644 docs/en/setup/service-agent/virtual-database.md

diff --git a/CHANGES.md b/CHANGES.md
index 4765afa2e0..2d8febd82e 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -180,6 +180,7 @@ NOTICE, this sharding concept is NOT just for splitting data into different data
 * Remove `All` source relative document and examples.
 * Update Booster UI's dependency licenses.
 * Add profiling doc, and remove service mesh intro doc(not necessary).
+* Add a doc for virtual database.
 
 All issues and pull requests are [here](https://github.com/apache/skywalking/milestone/112?closed=1)
 
diff --git a/docs/en/setup/service-agent/virtual-database.md b/docs/en/setup/service-agent/virtual-database.md
new file mode 100644
index 0000000000..fcef2ca042
--- /dev/null
+++ b/docs/en/setup/service-agent/virtual-database.md
@@ -0,0 +1,15 @@
+# Virtual Database
+
+Virtual databases represents the database nodes detected by [server agents' plugins](server-agents.md). The performance
+metrics of the databases are also from Database client side perspective.
+
+For example, JDBC plugins(MySQL, PostgreSQL, Mariadb, MSSQL) in the Java agent could detect the latency of SQL
+performance, as well as SQL statements. As a result, in this dashboard, SkyWalking would show database traffic, latency,
+success rate and sampled slow SQLs powered by backend analysis capabilities.
+
+The Database access span should have
+- It is an **Exit** span
+- **Span's layer == DATABASE**
+- Tag key = `db.statement`, value = SQL statement
+- Tag key = `db.type`, value = the type of Database
+- Span's peer is the network address(IP or domain) of Database server.
diff --git a/docs/menu.yml b/docs/menu.yml
index 7d93562fc1..5f79779d95 100644
--- a/docs/menu.yml
+++ b/docs/menu.yml
@@ -165,6 +165,10 @@ catalog:
                 path: "/en/setup/backend/backend-vm-monitoring"
           - name: "Browser Monitoring"
             path: "/en/setup/service-agent/browser-agent"
+          - name: "Database Monitoring"
+            catalog:
+              - name: "Virtual Database"
+                path: "en/setup/service-agent/virtual-database"
           - name: "Self Observability"
             catalog:
               - name: "OAP Telemetry"