diff --git a/src/main/scala/gitbucket/core/controller/SystemSettingsController.scala b/src/main/scala/gitbucket/core/controller/SystemSettingsController.scala
index e0226ef..1287501 100644
--- a/src/main/scala/gitbucket/core/controller/SystemSettingsController.scala
+++ b/src/main/scala/gitbucket/core/controller/SystemSettingsController.scala
@@ -27,7 +27,7 @@
   with AccountService with RepositoryService with AdminAuthenticator
 
 case class Table(name: String, columns: Seq[Column])
-case class Column(name: String)
+case class Column(name: String, primaryKey: Boolean)
 
 trait SystemSettingsControllerBase extends AccountManagementControllerBase {
   self: AccountService with RepositoryService with AdminAuthenticator =>
@@ -165,10 +165,19 @@
     using(meta.getTables(null, "%", "%", Array("TABLE", "VIEW"))){ rs =>
       while(rs.next()){
         val tableName = rs.getString("TABLE_NAME")
+
+        val pkColumns = ListBuffer[String]()
+        using(meta.getPrimaryKeys(null, null, tableName)){ rs =>
+          while(rs.next()){
+            pkColumns += rs.getString("COLUMN_NAME").toUpperCase
+          }
+        }
+
         val columns = ListBuffer[Column]()
         using(meta.getColumns(null, "%", tableName, "%")){ rs =>
           while(rs.next()){
-            columns += Column(rs.getString("COLUMN_NAME").toUpperCase)
+            val columnName = rs.getString("COLUMN_NAME").toUpperCase
+            columns += Column(columnName, pkColumns.contains(columnName))
           }
         }
 
diff --git a/src/main/twirl/gitbucket/core/admin/dbviewer.scala.html b/src/main/twirl/gitbucket/core/admin/dbviewer.scala.html
index e0eab7e..3dc0ddb 100644
--- a/src/main/twirl/gitbucket/core/admin/dbviewer.scala.html
+++ b/src/main/twirl/gitbucket/core/admin/dbviewer.scala.html
@@ -10,7 +10,9 @@
             <li data-jstree='{"icon":"@context.path/assets/common/images/table.gif"}'><a href="javascript:void(0);" class="table-link">@table.name</a>
               <ul>
               @table.columns.map { column =>
-                <li data-jstree='{"icon":"@context.path/assets/common/images/column.gif"}'>@column.name</li>
+                <li data-jstree='{"icon":"@context.path/assets/common/images/column.gif"}'>@column.name
+                  @if(column.primaryKey){ (PK) }
+                </li>
               }
               </ul>
             </li>