diff --git a/htdocs/install/mysql/tables/llx_element_tag.key.sql b/htdocs/install/mysql/tables/llx_element_tag.key.sql
index e4af1c3871e..d3a0b38afa9 100644
--- a/htdocs/install/mysql/tables/llx_element_tag.key.sql
+++ b/htdocs/install/mysql/tables/llx_element_tag.key.sql
@@ -16,8 +16,6 @@
 --
 -- ============================================================================
 
-ALTER TABLE llx_element_tag ADD PRIMARY KEY pk_element_tag (fk_categorie, fk_element);
-ALTER TABLE llx_element_tag ADD INDEX idx_element_tag_fk_categorie (fk_categorie);
-ALTER TABLE llx_element_tag ADD INDEX idx_element_tag_fk_element (fk_element);
+ALTER TABLE llx_element_tag ADD UNIQUE INDEX idx_element_tag_uk (fk_categorie, fk_element);
 
 ALTER TABLE llx_element_tag ADD CONSTRAINT fk_element_tag_categorie_rowid FOREIGN KEY (fk_categorie) REFERENCES llx_categorie (rowid);
diff --git a/htdocs/install/mysql/tables/llx_element_tag.sql b/htdocs/install/mysql/tables/llx_element_tag.sql
index 937137727e7..d43ced98130 100644
--- a/htdocs/install/mysql/tables/llx_element_tag.sql
+++ b/htdocs/install/mysql/tables/llx_element_tag.sql
@@ -18,6 +18,7 @@
 
 create table llx_element_tag
 (
+  rowid integer AUTO_INCREMENT PRIMARY KEY,
   fk_categorie  integer NOT NULL,
   fk_element  integer NOT NULL,
   import_key    varchar(14)