diff --git a/composer.json b/composer.json
index c92574995..98ba7833b 100644
--- a/composer.json
+++ b/composer.json
@@ -16,6 +16,11 @@
 			"minus-x fix .",
 			"phpcbf"
 		],
+		"dbschema": [
+			"php ../../maintenance/generateSchemaSql.php --json sql/discussiontools_subscription.json --sql sql/mysql/discussiontools_subscription.sql --type mysql",
+			"php ../../maintenance/generateSchemaSql.php --json sql/discussiontools_subscription.json --sql sql/postgres/discussiontools_subscription.sql --type postgres",
+			"php ../../maintenance/generateSchemaSql.php --json sql/discussiontools_subscription.json --sql sql/sqlite/discussiontools_subscription.sql --type sqlite"
+		],
 		"phan": "phan -d . --long-progress-bar"
 	}
 }
diff --git a/extension.json b/extension.json
index 1e0ff4a87..1822f322b 100644
--- a/extension.json
+++ b/extension.json
@@ -350,6 +350,7 @@
 		"discussiontoolsedit": "MediaWiki\\Extension\\DiscussionTools\\ApiDiscussionToolsEdit"
 	},
 	"Hooks": {
+		"LoadExtensionSchemaUpdates": "installer",
 		"ArticleParserOptions": "parser",
 		"ParserAfterTidy": "parser",
 		"ParserOptionsRegister": "parser",
@@ -363,6 +364,9 @@
 		"RecentChange_save": "tags"
 	},
 	"HookHandlers": {
+		"installer": {
+			"class": "MediaWiki\\Extension\\DiscussionTools\\Hooks\\InstallerHooks"
+		},
 		"page": {
 			"class": "MediaWiki\\Extension\\DiscussionTools\\Hooks\\PageHooks"
 		},
diff --git a/includes/Hooks/InstallerHooks.php b/includes/Hooks/InstallerHooks.php
new file mode 100644
index 000000000..71eb55456
--- /dev/null
+++ b/includes/Hooks/InstallerHooks.php
@@ -0,0 +1,34 @@
+<?php
+/**
+ * DiscussionTools installer hooks
+ *
+ * @file
+ * @ingroup Extensions
+ * @license MIT
+ */
+
+namespace MediaWiki\Extension\DiscussionTools\Hooks;
+
+use DatabaseUpdater;
+use MediaWiki\Installer\Hook\LoadExtensionSchemaUpdatesHook;
+
+class InstallerHooks implements
+	LoadExtensionSchemaUpdatesHook
+{
+	/**
+	 * Implements the LoadExtensionSchemaUpdates hook, to create database tables when
+	 * update.php runs
+	 *
+	 * @param DatabaseUpdater $updater
+	 * @return bool|void
+	 */
+	public function onLoadExtensionSchemaUpdates( $updater ) {
+		$base = dirname( __DIR__ );
+		$type = $updater->getDB()->getType();
+
+		$updater->addExtensionTable(
+			'discussiontools_subscription',
+			"$base/../sql/$type/discussiontools_subscription.sql"
+		);
+	}
+}
diff --git a/sql/discussiontools_subscription.json b/sql/discussiontools_subscription.json
new file mode 100644
index 000000000..ae07dd9ad
--- /dev/null
+++ b/sql/discussiontools_subscription.json
@@ -0,0 +1,109 @@
+[
+	{
+		"name": "discussiontools_subscription",
+		"columns": [
+			{
+				"name": "sub_id",
+				"type": "integer",
+				"options": {
+					"autoincrement": true,
+					"unsigned": true,
+					"notnull": true
+				}
+			},
+			{
+				"name": "sub_item",
+				"comment": "Internal name used to identify this item across all pages and revisions where it might appear, see CommentParser::computeName()",
+				"type": "string",
+				"options": {
+					"notnull": true,
+					"length": 255
+				}
+			},
+			{
+				"name": "sub_namespace",
+				"comment": "Namespace of the page where this item appeared when the user subscribed to it",
+				"type": "integer",
+				"options": {
+					"notnull": true,
+					"default": 0
+				}
+			},
+			{
+				"name": "sub_title",
+				"comment": "Title of the page where this item appeared when the user subscribed to it",
+				"type": "string",
+				"options": {
+					"notnull": true,
+					"length": 255
+				}
+			},
+			{
+				"name": "sub_section",
+				"comment": "Section of the page where this item appeared when the user subscribed to it",
+				"type": "string",
+				"options": {
+					"notnull": true,
+					"length": 255
+				}
+			},
+			{
+				"name": "sub_state",
+				"comment": "0: unsubscribed; 1: subscribed",
+				"type": "integer",
+				"options": {
+					"notnull": true,
+					"default": 1,
+					"length": 1
+				}
+			},
+			{
+				"name": "sub_user",
+				"comment": "User who is subscribed, key to user.user_id",
+				"type": "integer",
+				"options": {
+					"unsigned": true,
+					"notnull": true
+				}
+			},
+			{
+				"name": "sub_created",
+				"comment": "Time when this subscription was created",
+				"type": "mwtimestamp",
+				"options": {
+					"notnull": true
+				}
+			},
+			{
+				"name": "sub_notified",
+				"comment": "Time when a notification about the item was last sent",
+				"type": "mwtimestamp",
+				"options": {
+					"notnull": false
+				}
+			}
+		],
+		"indexes": [
+			{
+				"name": "discussiontools_subscription_itemuser",
+				"comment": "Index for finding all users subscribed to an item, or a specific subscription",
+				"columns": [
+					"sub_item",
+					"sub_user"
+				],
+				"unique": true
+			},
+			{
+				"name": "discussiontools_subscription_user",
+				"comment": "Index for finding all subscriptions of the user",
+				"columns": [
+					"sub_user"
+				],
+				"unique": false
+			}
+		],
+		"pk": [
+			"sub_id"
+		]
+	}
+]
diff --git a/sql/mysql/discussiontools_subscription.sql b/sql/mysql/discussiontools_subscription.sql
new file mode 100644
index 000000000..5a36b8863
--- /dev/null
+++ b/sql/mysql/discussiontools_subscription.sql
@@ -0,0 +1,18 @@
+-- This file is automatically generated using maintenance/generateSchemaSql.php.
+-- Source: sql/discussiontools_subscription.json
+-- Do not modify this file directly.
+-- See https://www.mediawiki.org/wiki/Manual:Schema_changes
+CREATE TABLE /*_*/discussiontools_subscription (
+  sub_id INT UNSIGNED AUTO_INCREMENT NOT NULL,
+  sub_item VARCHAR(255) NOT NULL,
+  sub_namespace INT DEFAULT 0 NOT NULL,
+  sub_title VARCHAR(255) NOT NULL,
+  sub_section VARCHAR(255) NOT NULL,
+  sub_state INT DEFAULT 1 NOT NULL,
+  sub_user INT UNSIGNED NOT NULL,
+  sub_created BINARY(14) NOT NULL,
+  sub_notified BINARY(14) DEFAULT NULL,
+  UNIQUE INDEX discussiontools_subscription_itemuser (sub_item, sub_user),
+  INDEX discussiontools_subscription_user (sub_user),
+  PRIMARY KEY(sub_id)
+) /*$wgDBTableOptions*/;
diff --git a/sql/postgres/discussiontools_subscription.sql b/sql/postgres/discussiontools_subscription.sql
new file mode 100644
index 000000000..112f7dde5
--- /dev/null
+++ b/sql/postgres/discussiontools_subscription.sql
@@ -0,0 +1,20 @@
+-- This file is automatically generated using maintenance/generateSchemaSql.php.
+-- Source: sql/discussiontools_subscription.json
+-- Do not modify this file directly.
+-- See https://www.mediawiki.org/wiki/Manual:Schema_changes
+CREATE TABLE discussiontools_subscription (
+  sub_id SERIAL NOT NULL,
+  sub_item VARCHAR(255) NOT NULL,
+  sub_namespace INT DEFAULT 0 NOT NULL,
+  sub_title VARCHAR(255) NOT NULL,
+  sub_section VARCHAR(255) NOT NULL,
+  sub_state INT DEFAULT 1 NOT NULL,
+  sub_user INT NOT NULL,
+  sub_created TIMESTAMPTZ NOT NULL,
+  sub_notified TIMESTAMPTZ DEFAULT NULL,
+  PRIMARY KEY(sub_id)
+);
+
+CREATE UNIQUE INDEX discussiontools_subscription_itemuser ON discussiontools_subscription (sub_item, sub_user);
+
+CREATE INDEX discussiontools_subscription_user ON discussiontools_subscription (sub_user);
diff --git a/sql/sqlite/discussiontools_subscription.sql b/sql/sqlite/discussiontools_subscription.sql
new file mode 100644
index 000000000..58b0cd52f
--- /dev/null
+++ b/sql/sqlite/discussiontools_subscription.sql
@@ -0,0 +1,19 @@
+-- This file is automatically generated using maintenance/generateSchemaSql.php.
+-- Source: sql/discussiontools_subscription.json
+-- Do not modify this file directly.
+-- See https://www.mediawiki.org/wiki/Manual:Schema_changes
+CREATE TABLE /*_*/discussiontools_subscription (
+  sub_id INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL,
+  sub_item VARCHAR(255) NOT NULL,
+  sub_namespace INTEGER DEFAULT 0 NOT NULL,
+  sub_title VARCHAR(255) NOT NULL,
+  sub_section VARCHAR(255) NOT NULL,
+  sub_state INTEGER DEFAULT 1 NOT NULL,
+  sub_user INTEGER UNSIGNED NOT NULL,
+  sub_created BLOB NOT NULL,
+  sub_notified BLOB DEFAULT NULL
+);
+
+CREATE UNIQUE INDEX discussiontools_subscription_itemuser ON /*_*/discussiontools_subscription (sub_item, sub_user);
+
+CREATE INDEX discussiontools_subscription_user ON /*_*/discussiontools_subscription (sub_user);