diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9f51e81..5018286 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - System wide values option
 - Allow email login option
 - UID user table column
+- GID user table column
 
 ## [4.4.1] - 2020-02-02
 ### Fixed
diff --git a/README.md b/README.md
index 76294da..c71f1cd 100644
--- a/README.md
+++ b/README.md
@@ -69,7 +69,7 @@ The definition of user table. The table containing user accounts.
 Name | Description | Details
 --- | --- | ---
 **Table name** | The table name. | Mandatory for user backend.
-**UID** | UID column. | Mandatory for user backend.
+**UID** | User ID column. | Mandatory for user backend.
 **Username** | Username column. | Optional.
 **Email** | E-mail column. | Mandatory for *Email sync* option.
 **Quota** | Quota column. | Mandatory for *Quota sync* option.
@@ -90,9 +90,9 @@ The group definitions table.
 Name | Description | Details
 --- | --- | ---
 **Table name** | The table name. | Mandatory for group backend.
-**Is admin** | Flag indicating if its the admin group | Optional.
+**GID** | Group ID column. | Mandatory for group backend.
 **Display name** | Display name column. | Optional.
-**Group name** | Group name column. | Mandatory for group backend.
+**Is admin** | Flag indicating if its the admin group | Optional.
 
 #### User group table
 
@@ -101,8 +101,8 @@ Associative table which maps users to groups.
 Name | Description | Details
 --- | --- | ---
 **Table name** | The table name. | Mandatory for group backend.
-**Username** | Username column. | Mandatory for group backend.
-**Group name** | Group name column. | Mandatory for group backend.
+**UID** | User ID column. | Mandatory for group backend.
+**GID** | Group ID column. | Mandatory for group backend.
 
 ## Integrations
 
@@ -135,20 +135,20 @@ CREATE TABLE sql_user
 
 CREATE TABLE sql_group
 (
-  name         VARCHAR(16) PRIMARY KEY,
-  display_name TEXT        NULL,
-  admin        BOOLEAN     NOT NULL DEFAULT FALSE
+  gid   INT         PRIMARY KEY AUTO_INCREMENT,
+  name  VARCHAR(16) NOT NULL UNIQUE,
+  admin BOOLEAN     NOT NULL DEFAULT FALSE
 );
 
 CREATE TABLE sql_user_group
 (
-  username   VARCHAR(16) NOT NULL,
-  group_name VARCHAR(16) NOT NULL,
-  PRIMARY KEY (username, group_name),
-  FOREIGN KEY (username) REFERENCES sql_user (username),
-  FOREIGN KEY (group_name) REFERENCES sql_group (name),
-  INDEX sql_user_group_username_idx (username),
-  INDEX sql_user_group_group_name_idx (group_name)
+  uid INT NOT NULL,
+  gid INT NOT NULL,
+  PRIMARY KEY (uid, gid),
+  FOREIGN KEY (uid) REFERENCES sql_user (uid),
+  FOREIGN KEY (gid) REFERENCES sql_group (gid),
+  INDEX user_group_username_idx (uid),
+  INDEX user_group_group_name_idx (gid)
 );
 ```
 
diff --git a/lib/Query/DataQuery.php b/lib/Query/DataQuery.php
index 8f7f990..55bef51 100644
--- a/lib/Query/DataQuery.php
+++ b/lib/Query/DataQuery.php
@@ -115,7 +115,7 @@ class DataQuery
         }
 
         $this->logger->debug(
-            "Executing query:" . $query . ", " . implode(",", $params),
+            "Executing query: " . $query . ", " . implode(",", $params),
             ["app" => $this->appName]
         );
 
diff --git a/templates/admin.php b/templates/admin.php
index 16be704..e306adc 100644
--- a/templates/admin.php
+++ b/templates/admin.php
@@ -179,9 +179,9 @@ function print_select_options(
                 print_text_input($l, "db-table-group", "Table name", $_["db.table.group"]); ?>
                 <h3><?php p($l->t("Columns")); ?></h3>
                 <?php
-                print_text_input($l, "db-table-group-column-admin", "Is admin", $_["db.table.group.column.admin"]);
+                print_text_input($l, "db-table-group-column-gid", "GID", $_["db.table.group.column.gid"]);
                 print_text_input($l, "db-table-group-column-name", "Display name", $_["db.table.group.column.name"]);
-                print_text_input($l, "db-table-group-column-gid", "Group name", $_["db.table.group.column.gid"]); ?>
+                print_text_input($l, "db-table-group-column-admin", "Is admin", $_["db.table.group.column.admin"]); ?>
             </fieldset>
         </div>
         <div class="section">
@@ -191,8 +191,8 @@ function print_select_options(
                 print_text_input($l, "db-table-user_group", "Table name", $_["db.table.user_group"]); ?>
                 <h3><?php p($l->t("Columns")); ?></h3>
                 <?php
-                print_text_input($l, "db-table-user_group-column-uid", "Username", $_["db.table.user_group.column.uid"]);
-                print_text_input($l, "db-table-user_group-column-gid", "Group name", $_["db.table.user_group.column.gid"]); ?>
+                print_text_input($l, "db-table-user_group-column-uid", "UID", $_["db.table.user_group.column.uid"]);
+                print_text_input($l, "db-table-user_group-column-gid", "GID", $_["db.table.user_group.column.gid"]); ?>
             </fieldset>
         </div>
     </div>