diff --git a/lib/conf.d/bases_structure.xml b/lib/conf.d/bases_structure.xml
index 11a023db36..b4ef728f8f 100644
--- a/lib/conf.d/bases_structure.xml
+++ b/lib/conf.d/bases_structure.xml
@@ -5298,7 +5298,15 @@
               <field>id</field>
             </fields>
           </index>
-           <index>
+          <index>
+            <name>couple</name>
+            <type>UNIQUE</type>
+            <fields>
+              <field>log_id</field>
+              <field>coll_id</field>
+            </fields>
+          </index>
+          <index>
             <name>log_id</name>
             <type>INDEX</type>
             <fields>