diff --git a/.github/workflows/ci-linux.yml b/.github/workflows/ci-linux.yml
index 559660c4..2430a859 100644
--- a/.github/workflows/ci-linux.yml
+++ b/.github/workflows/ci-linux.yml
@@ -11,6 +11,9 @@ on:
   # Enable manual run
   workflow_dispatch:
 
+permissions:
+  contents: read
+
 concurrency:
   group: "${{ github.workflow }}-${{ github.ref }}"
   cancel-in-progress: true
@@ -213,3 +216,97 @@ jobs:
         run: |
           cd galette-core/galette/plugins/plugin-events
           ../../vendor/bin/phpunit --test-suffix=.php --bootstrap tests/TestsBootstrap.php --no-coverage --process-isolation tests/GaletteEvents/
+
+  upgrade:
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        db-image: ['mysql:8.4', 'mariadb:11', 'postgres:17']
+      fail-fast: false
+
+    env:
+      DB: ${{ matrix.db-image }}
+
+    services:
+      # Label used to access the service container
+      db:
+        # Docker Hub image
+        image: ${{ matrix.db-image }}
+        # Provide env variables for both mysql and pgsql
+        env:
+          POSTGRES_USER: galette_tests
+          POSTGRES_PASSWORD: g@l3tte
+          POSTGRES_DB: galette_tests
+          MYSQL_USER: galette_tests
+          MYSQL_PASSWORD: g@l3tte
+          MYSQL_ROOT_PASSWORD: g@l3tte
+          MYSQL_DATABASE: galette_tests
+        # Open network ports for both mysql and pgsql
+        ports:
+          - 3306:3306
+          - 5432:5432
+        # Set health checks to wait until postgres has started
+        options: >-
+          --health-cmd="bash -c 'if [[ -n $(command -v pg_isready) ]]; then pg_isready; else if [[ -n $(command -v mysqladmin) ]]; then mysqladmin ping; else mariadb-admin ping; fi fi'"
+          --health-interval=10s
+          --health-timeout=5s
+          --health-retries=10
+
+    name: Upgrade from previous release on ${{ matrix.db-image }}
+
+    steps:
+      - name: PHP
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: '8.4'
+          tools: composer, pecl
+          coverage: none
+          extensions: apcu
+          ini-values: apc.enable_cli=1
+
+      - name: Build Galette
+        uses: galette/.github/actions/build-galette@main
+        with:
+          php-version: '8.4'
+
+      - name: Checkout plugin
+        uses: actions/checkout@v7
+        with:
+          path: galette-core/galette/plugins/plugin-events
+          fetch-depth: 0
+
+      - name: Find previous release
+        run: |
+          cd galette-core/galette/plugins/plugin-events
+          echo "PREVIOUS_RELEASE=$(git tag --list '[0-9]*' --sort=-v:refname --no-contains HEAD | head -n1)" >> $GITHUB_ENV
+
+      - name: Install previous release for PostgreSQL
+        env:
+          PGPASSWORD: g@l3tte
+        run: |
+          cd galette-core
+          bin/console galette:install -v --dbtype=pgsql --dbhost=localhost --dbname=galette_tests --dbuser=galette_tests --dbpass=g@l3tte --admin=admin --password=admin --no-interaction -w
+          git -C galette/plugins/plugin-events show "$PREVIOUS_RELEASE:scripts/pgsql.sql" \
+            | psql -v ON_ERROR_STOP=1 -h localhost -U galette_tests galette_tests
+        if: startsWith(matrix.db-image, 'postgres')
+
+      - name: Install previous release for MariaDB
+        run: |
+          cd galette-core
+          mysql -e 'create database IF NOT EXISTS galette_tests;' -u galette_tests --password=g@l3tte -h 127.0.0.1 -P 3306
+          bin/console galette:install -v --dbtype=mysql --dbhost=127.0.0.1 --dbname=galette_tests --dbuser=galette_tests --dbpass=g@l3tte --admin=admin --password=admin --no-interaction -w
+          git -C galette/plugins/plugin-events show "$PREVIOUS_RELEASE:scripts/mysql.sql" \
+            | mysql -u galette_tests --password=g@l3tte -h 127.0.0.1 -P 3306 galette_tests
+        if: startsWith(matrix.db-image, 'mysql') || startsWith(matrix.db-image, 'mariadb')
+
+      - name: Upgrade
+        run: |
+          cd galette-core
+          bin/console galette:plugins:install-db --no-interaction plugin-events | tee upgrade.log
+          grep -q 'Database for plugin "plugin-events" upgraded' upgrade.log
+
+      - name: Unit tests
+        run: |
+          cd galette-core/galette/plugins/plugin-events
+          ../../vendor/bin/phpunit --test-suffix=.php --bootstrap tests/TestsBootstrap.php --no-coverage --process-isolation tests/GaletteEvents/
diff --git a/_define.php b/_define.php
index b664e066..93ea4e6e 100644
--- a/_define.php
+++ b/_define.php
@@ -48,5 +48,5 @@
         'events_calendar'           => 'member',
         'ajax-events_calendar'      => 'member'
     ],
-    dbver: 1.00
+    dbver: 1.1
 );
diff --git a/lang/events.pot b/lang/events.pot
index 9c786da6..abb9c884 100644
--- a/lang/events.pot
+++ b/lang/events.pot
@@ -8,7 +8,7 @@ msgid ""
 msgstr ""
 "Project-Id-Version: PACKAGE VERSION\n"
 "Report-Msgid-Bugs-To: \n"
-"POT-Creation-Date: 2026-09-25 04:15+0200\n"
+"POT-Creation-Date: 2026-09-27 08:45+0200\n"
 "PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
 "Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
 "Language-Team: LANGUAGE <LL@li.org>\n"
@@ -18,81 +18,93 @@ msgstr ""
 "Content-Transfer-Encoding: 8bit\n"
 "Plural-Forms: nplurals=INTEGER; plural=EXPRESSION;\n"
 
-#: ../lib/GaletteEvents/Event.php:188
+#: ../lib/GaletteEvents/Event.php:182
 msgid "Begin date is mandatory"
 msgstr ""
 
-#: ../lib/GaletteEvents/Event.php:212 ../templates/default/event.html.twig:40
+#: ../lib/GaletteEvents/Event.php:206 ../templates/default/event.html.twig:40
 msgid "Begin date"
 msgstr ""
 
-#: ../lib/GaletteEvents/Event.php:214 ../templates/default/event.html.twig:46
+#: ../lib/GaletteEvents/Event.php:208 ../templates/default/event.html.twig:46
 msgid "End date"
 msgstr ""
 
-#: ../lib/GaletteEvents/Event.php:232
+#: ../lib/GaletteEvents/Event.php:226
 msgid "End date must be later or equal to begin date"
 msgstr ""
 
-#: ../lib/GaletteEvents/Event.php:238 ../lib/GaletteEvents/Activity.php:155
+#: ../lib/GaletteEvents/Event.php:232 ../lib/GaletteEvents/Activity.php:155
 msgid "Name is mandatory"
 msgstr ""
 
-#: ../lib/GaletteEvents/Event.php:254
+#: ../lib/GaletteEvents/Event.php:248
 msgid "Please select a group you own!"
 msgstr ""
 
-#: ../lib/GaletteEvents/Event.php:261
+#: ../lib/GaletteEvents/Event.php:255
 msgid "Town is mandatory"
 msgstr ""
 
-#: ../lib/GaletteEvents/Event.php:388
+#: ../lib/GaletteEvents/Event.php:380
 msgid "Event added"
 msgstr ""
 
-#: ../lib/GaletteEvents/Event.php:392
+#: ../lib/GaletteEvents/Event.php:384
 msgid "Fail to add new event."
 msgstr ""
 
-#: ../lib/GaletteEvents/Event.php:411
+#: ../lib/GaletteEvents/Event.php:403
 msgid "Event updated"
 msgstr ""
 
-#: ../lib/GaletteEvents/Controllers/CsvController.php:54
-#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:257
+#. TRANS: %1$s is the group name, %2$s the number of events
+#: ../lib/GaletteEvents/PluginEventProvider.php:58
+#, php-format
+msgid ""
+"Group \"%1$s\" is used by %2$s event, it cannot be deleted. Remove the event "
+"or change its group first."
+msgid_plural ""
+"Group \"%1$s\" is used by %2$s events, it cannot be deleted. Remove the "
+"events or change their group first."
+msgstr[0] ""
+msgstr[1] ""
+
+#: ../lib/GaletteEvents/Controllers/CsvController.php:86
+#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:226
 #: ../templates/default/booking.html.twig:33 ../templates/default/booking.html.twig:39
 #: ../templates/default/bookings.html.twig:49 ../templates/default/bookings.html.twig:77
 msgid "Event"
 msgstr ""
 
-#: ../lib/GaletteEvents/Controllers/CsvController.php:58
+#: ../lib/GaletteEvents/Controllers/CsvController.php:90
 #: ../templates/default/event.html.twig:86
 msgid "Zip code"
 msgstr ""
 
-#: ../lib/GaletteEvents/Controllers/CsvController.php:64
+#: ../lib/GaletteEvents/Controllers/CsvController.php:96
 #: ../templates/default/booking.html.twig:63
 msgid "Number of persons"
 msgstr ""
 
-#: ../lib/GaletteEvents/Controllers/CsvController.php:79
+#: ../lib/GaletteEvents/Controllers/CsvController.php:111
 #: ../templates/default/booking.html.twig:115
 msgid "Amount"
 msgstr ""
 
-#: ../lib/GaletteEvents/Controllers/CsvController.php:81
+#: ../lib/GaletteEvents/Controllers/CsvController.php:113
 #: ../templates/default/booking.html.twig:127
 msgid "Bank name"
 msgstr ""
 
 #. TRANS: Bank check number
-#: ../lib/GaletteEvents/Controllers/CsvController.php:83
+#: ../lib/GaletteEvents/Controllers/CsvController.php:115
 #: ../templates/default/booking.html.twig:133
 msgid "Check number"
 msgstr ""
 
 #. TRANS: this is a filename: all lowercase, no special character, no space.
-#: ../lib/GaletteEvents/Controllers/CsvController.php:138
+#: ../lib/GaletteEvents/Controllers/CsvController.php:170
 msgid "bookingslist"
 msgstr ""
 
@@ -100,79 +112,86 @@ msgstr ""
 msgid "Events management"
 msgstr ""
 
-#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:153
+#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:128
 msgid "Javascript libraries has not been built!"
 msgstr ""
 
-#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:162
-#: ../lib/GaletteEvents/PluginGaletteEvents.php:139
+#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:137
+#: ../lib/GaletteEvents/PluginGaletteEvents.php:136
 msgid "Events calendar"
 msgstr ""
 
-#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:336
+#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:288
 msgid "Activity has been attached to event."
 msgstr ""
 
-#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:337
+#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:289
+#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:295
 msgid "Do not forget to store the event"
 msgstr ""
 
-#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:339
+#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:291
+#: ../templates/default/event.html.twig:179
+msgid "Please choose an activity to add"
+msgstr ""
+
+#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:294
 msgid "Activity has been detached from event."
 msgstr ""
 
-#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:348
+#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:303
 msgid "New event has been successfully added."
 msgstr ""
 
-#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:350
+#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:305
 msgid "Event has been modified."
 msgstr ""
 
-#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:354
+#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:308
 msgid "An error occurred while storing the event."
 msgstr ""
 
 #. TRANS: %1$s is the event name
-#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:448
+#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:417
 #, php-format
 msgid "Remove event '%1$s'"
 msgstr ""
 
-#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:133
+#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:134
 msgid "Bookings management"
 msgstr ""
 
-#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:291
-msgid "No action was matching."
+#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:258
+#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:322
+msgid "No booking was selected, please check at least one."
 msgstr ""
 
-#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:296
-msgid "No booking was selected, please check at least one."
+#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:317
+msgid "No action was matching."
 msgstr ""
 
-#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:332
+#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:381
 msgid "Booking"
 msgstr ""
 
-#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:457
+#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:510
 msgid "New booking has been successfully added."
 msgstr ""
 
-#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:459
+#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:512
 msgid "Booking has been modified."
 msgstr ""
 
-#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:463
+#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:516
 msgid "An error occurred while storing the booking."
 msgstr ""
 
-#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:471
+#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:524
 msgid "Do not forget to store the booking"
 msgstr ""
 
 #. TRANS: %1$s is the member name, %2$s the event name.
-#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:568
+#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:641
 #, php-format
 msgid "Remove booking for %1$s on %2$s"
 msgstr ""
@@ -203,51 +222,63 @@ msgstr ""
 msgid "Remove activity %1$s"
 msgstr ""
 
-#: ../lib/GaletteEvents/Booking.php:175
+#: ../lib/GaletteEvents/Booking.php:177
 msgid "Event is mandatory"
 msgstr ""
 
+#: ../lib/GaletteEvents/Booking.php:183
+msgid "This event cannot be booked."
+msgstr ""
+
 #. TRANS: %1$s is activity name
-#: ../lib/GaletteEvents/Booking.php:187
+#: ../lib/GaletteEvents/Booking.php:193
 #, php-format
 msgid "%1$s is mandatory for this event!"
 msgstr ""
 
-#: ../lib/GaletteEvents/Booking.php:222
+#: ../lib/GaletteEvents/Booking.php:231
+msgid "Amount must be a number."
+msgstr ""
+
+#: ../lib/GaletteEvents/Booking.php:236
 msgid "Please specify amount if booking has been paid ;)"
 msgstr ""
 
-#: ../lib/GaletteEvents/Booking.php:245
+#: ../lib/GaletteEvents/Booking.php:257
 msgid "Member is mandatory"
 msgstr ""
 
-#: ../lib/GaletteEvents/Booking.php:257
+#: ../lib/GaletteEvents/Booking.php:271
+msgid "You can only book other members on events of groups you manage."
+msgstr ""
+
+#: ../lib/GaletteEvents/Booking.php:281
 msgid "There must be at least one person"
 msgstr ""
 
-#: ../lib/GaletteEvents/Booking.php:266
+#: ../lib/GaletteEvents/Booking.php:290
 msgid "Booking date is mandatory!"
 msgstr ""
 
-#: ../lib/GaletteEvents/Booking.php:290
+#: ../lib/GaletteEvents/Booking.php:314
 msgid "booking date"
 msgstr ""
 
 #. TRANS: first replacement is member name, second is event name
-#: ../lib/GaletteEvents/Booking.php:312
+#: ../lib/GaletteEvents/Booking.php:336
 #, php-format
 msgid "A booking already exists for %1$s in %2$s"
 msgstr ""
 
-#: ../lib/GaletteEvents/Booking.php:378
+#: ../lib/GaletteEvents/Booking.php:402
 msgid "Booking added"
 msgstr ""
 
-#: ../lib/GaletteEvents/Booking.php:382
+#: ../lib/GaletteEvents/Booking.php:406
 msgid "Fail to add new booking."
 msgstr ""
 
-#: ../lib/GaletteEvents/Booking.php:401
+#: ../lib/GaletteEvents/Booking.php:425
 msgid "Booking updated"
 msgstr ""
 
@@ -263,62 +294,62 @@ msgstr ""
 msgid "Activity updated"
 msgstr ""
 
-#: ../lib/GaletteEvents/Repository/Events.php:196
+#: ../lib/GaletteEvents/Repository/Events.php:170
 msgid "Event information"
 msgstr ""
 
-#: ../lib/GaletteEvents/Repository/Events.php:200
+#: ../lib/GaletteEvents/Repository/Events.php:174
 msgid "Start date:"
 msgstr ""
 
-#: ../lib/GaletteEvents/Repository/Events.php:201
+#: ../lib/GaletteEvents/Repository/Events.php:175
 msgid "End date:"
 msgstr ""
 
-#: ../lib/GaletteEvents/Repository/Events.php:202
+#: ../lib/GaletteEvents/Repository/Events.php:176
 msgid "Location:"
 msgstr ""
 
-#: ../lib/GaletteEvents/Repository/Events.php:204
+#: ../lib/GaletteEvents/Repository/Events.php:178
 msgid "Comment:"
 msgstr ""
 
 #. TRANS: %1$s is the number of paid attendees
-#: ../lib/GaletteEvents/Repository/Events.php:221
+#: ../lib/GaletteEvents/Repository/Events.php:195
 #, php-format
 msgid "%1$s paid"
 msgstr ""
 
-#: ../lib/GaletteEvents/Repository/Events.php:226
+#: ../lib/GaletteEvents/Repository/Events.php:200
 msgid "Attendees:"
 msgstr ""
 
-#: ../lib/GaletteEvents/Repository/Events.php:234
-#: ../lib/GaletteEvents/PluginGaletteEvents.php:96
+#: ../lib/GaletteEvents/Repository/Events.php:208
+#: ../lib/GaletteEvents/PluginGaletteEvents.php:93
 #: ../templates/default/booking.html.twig:78 ../templates/default/event.html.twig:108
 msgid "Activities"
 msgstr ""
 
-#: ../lib/GaletteEvents/PluginGaletteEvents.php:55
-#: ../lib/GaletteEvents/PluginGaletteEvents.php:59
+#: ../lib/GaletteEvents/PluginGaletteEvents.php:58
+#: ../lib/GaletteEvents/PluginGaletteEvents.php:62
 #: ../templates/default/activities.html.twig:41 ../templates/default/activities.html.twig:74
 msgid "Events"
 msgstr ""
 
-#: ../lib/GaletteEvents/PluginGaletteEvents.php:66
-#: ../lib/GaletteEvents/PluginGaletteEvents.php:138
+#: ../lib/GaletteEvents/PluginGaletteEvents.php:69
+#: ../lib/GaletteEvents/PluginGaletteEvents.php:135
 msgid "Calendar"
 msgstr ""
 
-#: ../lib/GaletteEvents/PluginGaletteEvents.php:79
+#: ../lib/GaletteEvents/PluginGaletteEvents.php:75
 msgid "Bookings"
 msgstr ""
 
-#: ../lib/GaletteEvents/PluginGaletteEvents.php:159
+#: ../lib/GaletteEvents/PluginGaletteEvents.php:156
 msgid "New event booking"
 msgstr ""
 
-#: ../lib/GaletteEvents/PluginGaletteEvents.php:215
+#: ../lib/GaletteEvents/PluginGaletteEvents.php:212
 msgid "Upcoming events"
 msgstr ""
 
@@ -374,7 +405,7 @@ msgstr ""
 msgid "Today"
 msgstr ""
 
-#: ../templates/default/calendar.html.twig:36 ../templates/default/bookings.html.twig:43
+#: ../templates/default/calendar.html.twig:33 ../templates/default/bookings.html.twig:43
 msgid "New booking"
 msgstr ""
 
@@ -555,7 +586,7 @@ msgstr ""
 msgid "No activity has been found"
 msgstr ""
 
-#: ../templates/default/event.html.twig:19
+#: ../templates/default/event.html.twig:17
 msgid "Is open"
 msgstr ""
 
@@ -607,10 +638,6 @@ msgstr ""
 msgid "No activity available in the database."
 msgstr ""
 
-#: ../templates/default/event.html.twig:179
-msgid "Please choose an activity to add"
-msgstr ""
-
 #: ../templates/default/event.html.twig:186
 msgid "Please choose an activity to remove"
 msgstr ""
diff --git a/lang/events_en_US.po b/lang/events_en_US.po
index 39c6d7b9..8dc055eb 100644
--- a/lang/events_en_US.po
+++ b/lang/events_en_US.po
@@ -7,8 +7,8 @@ msgid ""
 msgstr ""
 "Project-Id-Version: PACKAGE VERSION\n"
 "Report-Msgid-Bugs-To: \n"
-"POT-Creation-Date: 2026-09-25 04:15+0200\n"
-"PO-Revision-Date: 2026-09-25 04:15+0200\n"
+"POT-Creation-Date: 2026-09-27 08:45+0200\n"
+"PO-Revision-Date: 2026-09-27 08:45+0200\n"
 "Last-Translator: Automatically generated\n"
 "Language-Team: none\n"
 "Language: en_US\n"
@@ -17,48 +17,64 @@ msgstr ""
 "Content-Transfer-Encoding: 8bit\n"
 "Plural-Forms: nplurals=2; plural=(n != 1);\n"
 
-#: ../lib/GaletteEvents/Event.php:188
+#: ../lib/GaletteEvents/Event.php:182
 msgid "Begin date is mandatory"
 msgstr "Begin date is mandatory"
 
-#: ../lib/GaletteEvents/Event.php:212 ../templates/default/event.html.twig:40
+#: ../lib/GaletteEvents/Event.php:206 ../templates/default/event.html.twig:40
 msgid "Begin date"
 msgstr "Begin date"
 
-#: ../lib/GaletteEvents/Event.php:214 ../templates/default/event.html.twig:46
+#: ../lib/GaletteEvents/Event.php:208 ../templates/default/event.html.twig:46
 msgid "End date"
 msgstr "End date"
 
-#: ../lib/GaletteEvents/Event.php:232
+#: ../lib/GaletteEvents/Event.php:226
 msgid "End date must be later or equal to begin date"
 msgstr "End date must be later or equal to begin date"
 
-#: ../lib/GaletteEvents/Event.php:238 ../lib/GaletteEvents/Activity.php:155
+#: ../lib/GaletteEvents/Event.php:232 ../lib/GaletteEvents/Activity.php:155
 msgid "Name is mandatory"
 msgstr "Name is mandatory"
 
-#: ../lib/GaletteEvents/Event.php:254
+#: ../lib/GaletteEvents/Event.php:248
 msgid "Please select a group you own!"
 msgstr "Please select a group you own!"
 
-#: ../lib/GaletteEvents/Event.php:261
+#: ../lib/GaletteEvents/Event.php:255
 msgid "Town is mandatory"
 msgstr "Town is mandatory"
 
-#: ../lib/GaletteEvents/Event.php:388
+#: ../lib/GaletteEvents/Event.php:380
 msgid "Event added"
 msgstr "Event added"
 
-#: ../lib/GaletteEvents/Event.php:392
+#: ../lib/GaletteEvents/Event.php:384
 msgid "Fail to add new event."
 msgstr "Fail to add new event."
 
-#: ../lib/GaletteEvents/Event.php:411
+#: ../lib/GaletteEvents/Event.php:403
 msgid "Event updated"
 msgstr "Event updated"
 
-#: ../lib/GaletteEvents/Controllers/CsvController.php:54
-#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:257
+#. TRANS: %1$s is the group name, %2$s the number of events
+#: ../lib/GaletteEvents/PluginEventProvider.php:58
+#, php-format
+msgid ""
+"Group \"%1$s\" is used by %2$s event, it cannot be deleted. Remove the event "
+"or change its group first."
+msgid_plural ""
+"Group \"%1$s\" is used by %2$s events, it cannot be deleted. Remove the "
+"events or change their group first."
+msgstr[0] ""
+"Group \"%1$s\" is used by %2$s event, it cannot be deleted. Remove the event "
+"or change its group first."
+msgstr[1] ""
+"Group \"%1$s\" is used by %2$s events, it cannot be deleted. Remove the "
+"events or change their group first."
+
+#: ../lib/GaletteEvents/Controllers/CsvController.php:86
+#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:226
 #: ../templates/default/booking.html.twig:33
 #: ../templates/default/booking.html.twig:39
 #: ../templates/default/bookings.html.twig:49
@@ -66,34 +82,34 @@ msgstr "Event updated"
 msgid "Event"
 msgstr "Event"
 
-#: ../lib/GaletteEvents/Controllers/CsvController.php:58
+#: ../lib/GaletteEvents/Controllers/CsvController.php:90
 #: ../templates/default/event.html.twig:86
 msgid "Zip code"
 msgstr "Zip code"
 
-#: ../lib/GaletteEvents/Controllers/CsvController.php:64
+#: ../lib/GaletteEvents/Controllers/CsvController.php:96
 #: ../templates/default/booking.html.twig:63
 msgid "Number of persons"
 msgstr "Number of persons"
 
-#: ../lib/GaletteEvents/Controllers/CsvController.php:79
+#: ../lib/GaletteEvents/Controllers/CsvController.php:111
 #: ../templates/default/booking.html.twig:115
 msgid "Amount"
 msgstr "Amount"
 
-#: ../lib/GaletteEvents/Controllers/CsvController.php:81
+#: ../lib/GaletteEvents/Controllers/CsvController.php:113
 #: ../templates/default/booking.html.twig:127
 msgid "Bank name"
 msgstr "Bank name"
 
 #. TRANS: Bank check number
-#: ../lib/GaletteEvents/Controllers/CsvController.php:83
+#: ../lib/GaletteEvents/Controllers/CsvController.php:115
 #: ../templates/default/booking.html.twig:133
 msgid "Check number"
 msgstr "Check number"
 
 #. TRANS: this is a filename: all lowercase, no special character, no space.
-#: ../lib/GaletteEvents/Controllers/CsvController.php:138
+#: ../lib/GaletteEvents/Controllers/CsvController.php:170
 msgid "bookingslist"
 msgstr "bookingslist"
 
@@ -101,79 +117,86 @@ msgstr "bookingslist"
 msgid "Events management"
 msgstr "Events management"
 
-#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:153
+#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:128
 msgid "Javascript libraries has not been built!"
 msgstr "Javascript libraries has not been built!"
 
-#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:162
-#: ../lib/GaletteEvents/PluginGaletteEvents.php:139
+#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:137
+#: ../lib/GaletteEvents/PluginGaletteEvents.php:136
 msgid "Events calendar"
 msgstr "Events calendar"
 
-#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:336
+#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:288
 msgid "Activity has been attached to event."
 msgstr "Activity has been attached to event."
 
-#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:337
+#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:289
+#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:295
 msgid "Do not forget to store the event"
 msgstr "Do not forget to store the event"
 
-#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:339
+#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:291
+#: ../templates/default/event.html.twig:179
+msgid "Please choose an activity to add"
+msgstr "Please choose an activity to add"
+
+#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:294
 msgid "Activity has been detached from event."
 msgstr "Activity has been detached from event."
 
-#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:348
+#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:303
 msgid "New event has been successfully added."
 msgstr "New event has been successfully added."
 
-#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:350
+#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:305
 msgid "Event has been modified."
 msgstr "Event has been modified."
 
-#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:354
+#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:308
 msgid "An error occurred while storing the event."
 msgstr "An error occurred while storing the event."
 
 #. TRANS: %1$s is the event name
-#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:448
+#: ../lib/GaletteEvents/Controllers/Crud/EventsController.php:417
 #, php-format
 msgid "Remove event '%1$s'"
 msgstr "Remove event '%1$s'"
 
-#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:133
+#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:134
 msgid "Bookings management"
 msgstr "Bookings management"
 
-#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:291
-msgid "No action was matching."
-msgstr "No action was matching."
-
-#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:296
+#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:258
+#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:322
 msgid "No booking was selected, please check at least one."
 msgstr "No booking was selected, please check at least one."
 
-#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:332
+#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:317
+msgid "No action was matching."
+msgstr "No action was matching."
+
+#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:381
 msgid "Booking"
 msgstr "Booking"
 
-#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:457
+#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:510
 msgid "New booking has been successfully added."
 msgstr "New booking has been successfully added."
 
-#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:459
+#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:512
 msgid "Booking has been modified."
 msgstr "Booking has been modified."
 
-#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:463
+#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:516
 msgid "An error occurred while storing the booking."
 msgstr "An error occurred while storing the booking."
 
-#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:471
+#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:524
 msgid "Do not forget to store the booking"
 msgstr "Do not forget to store the booking"
 
 #. TRANS: %1$s is the member name, %2$s the event name.
-#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:568
+#: ../lib/GaletteEvents/Controllers/Crud/BookingsController.php:641
 #, php-format
 msgid "Remove booking for %1$s on %2$s"
 msgstr "Remove booking for %1$s on %2$s"
@@ -204,51 +227,63 @@ msgstr "An error occurred while storing the activity."
 msgid "Remove activity %1$s"
 msgstr "Remove activity %1$s"
 
-#: ../lib/GaletteEvents/Booking.php:175
+#: ../lib/GaletteEvents/Booking.php:177
 msgid "Event is mandatory"
 msgstr "Event is mandatory"
 
+#: ../lib/GaletteEvents/Booking.php:183
+msgid "This event cannot be booked."
+msgstr "This event cannot be booked."
+
 #. TRANS: %1$s is activity name
-#: ../lib/GaletteEvents/Booking.php:187
+#: ../lib/GaletteEvents/Booking.php:193
 #, php-format
 msgid "%1$s is mandatory for this event!"
 msgstr "%1$s is mandatory for this event!"
 
-#: ../lib/GaletteEvents/Booking.php:222
+#: ../lib/GaletteEvents/Booking.php:231
+msgid "Amount must be a number."
+msgstr "Amount must be a number."
+
+#: ../lib/GaletteEvents/Booking.php:236
 msgid "Please specify amount if booking has been paid ;)"
 msgstr "Please specify amount if booking has been paid ;)"
 
-#: ../lib/GaletteEvents/Booking.php:245
+#: ../lib/GaletteEvents/Booking.php:257
 msgid "Member is mandatory"
 msgstr "Member is mandatory"
 
-#: ../lib/GaletteEvents/Booking.php:257
+#: ../lib/GaletteEvents/Booking.php:271
+msgid "You can only book other members on events of groups you manage."
+msgstr "You can only book other members on events of groups you manage."
+
+#: ../lib/GaletteEvents/Booking.php:281
 msgid "There must be at least one person"
 msgstr "There must be at least one person"
 
-#: ../lib/GaletteEvents/Booking.php:266
+#: ../lib/GaletteEvents/Booking.php:290
 msgid "Booking date is mandatory!"
 msgstr "Booking date is mandatory!"
 
-#: ../lib/GaletteEvents/Booking.php:290
+#: ../lib/GaletteEvents/Booking.php:314
 msgid "booking date"
 msgstr "booking date"
 
 #. TRANS: first replacement is member name, second is event name
-#: ../lib/GaletteEvents/Booking.php:312
+#: ../lib/GaletteEvents/Booking.php:336
 #, php-format
 msgid "A booking already exists for %1$s in %2$s"
 msgstr "A booking already exists for %1$s in %2$s"
 
-#: ../lib/GaletteEvents/Booking.php:378
+#: ../lib/GaletteEvents/Booking.php:402
 msgid "Booking added"
 msgstr "Booking added"
 
-#: ../lib/GaletteEvents/Booking.php:382
+#: ../lib/GaletteEvents/Booking.php:406
 msgid "Fail to add new booking."
 msgstr "Fail to add new booking."
 
-#: ../lib/GaletteEvents/Booking.php:401
+#: ../lib/GaletteEvents/Booking.php:425
 msgid "Booking updated"
 msgstr "Booking updated"
 
@@ -264,64 +299,64 @@ msgstr "Fail to add new activity."
 msgid "Activity updated"
 msgstr "Activity updated"
 
-#: ../lib/GaletteEvents/Repository/Events.php:196
+#: ../lib/GaletteEvents/Repository/Events.php:170
 msgid "Event information"
 msgstr "Event information"
 
-#: ../lib/GaletteEvents/Repository/Events.php:200
+#: ../lib/GaletteEvents/Repository/Events.php:174
 msgid "Start date:"
 msgstr "Start date:"
 
-#: ../lib/GaletteEvents/Repository/Events.php:201
+#: ../lib/GaletteEvents/Repository/Events.php:175
 msgid "End date:"
 msgstr "End date:"
 
-#: ../lib/GaletteEvents/Repository/Events.php:202
+#: ../lib/GaletteEvents/Repository/Events.php:176
 msgid "Location:"
 msgstr "Location:"
 
-#: ../lib/GaletteEvents/Repository/Events.php:204
+#: ../lib/GaletteEvents/Repository/Events.php:178
 msgid "Comment:"
 msgstr "Comment:"
 
 #. TRANS: %1$s is the number of paid attendees
-#: ../lib/GaletteEvents/Repository/Events.php:221
+#: ../lib/GaletteEvents/Repository/Events.php:195
 #, php-format
 msgid "%1$s paid"
 msgstr "%1$s paid"
 
-#: ../lib/GaletteEvents/Repository/Events.php:226
+#: ../lib/GaletteEvents/Repository/Events.php:200
 msgid "Attendees:"
 msgstr "Attendees:"
 
-#: ../lib/GaletteEvents/Repository/Events.php:234
-#: ../lib/GaletteEvents/PluginGaletteEvents.php:96
+#: ../lib/GaletteEvents/Repository/Events.php:208
+#: ../lib/GaletteEvents/PluginGaletteEvents.php:93
 #: ../templates/default/booking.html.twig:78
 #: ../templates/default/event.html.twig:108
 msgid "Activities"
 msgstr "Activities"
 
-#: ../lib/GaletteEvents/PluginGaletteEvents.php:55
-#: ../lib/GaletteEvents/PluginGaletteEvents.php:59
+#: ../lib/GaletteEvents/PluginGaletteEvents.php:58
+#: ../lib/GaletteEvents/PluginGaletteEvents.php:62
 #: ../templates/default/activities.html.twig:41
 #: ../templates/default/activities.html.twig:74
 msgid "Events"
 msgstr "Events"
 
-#: ../lib/GaletteEvents/PluginGaletteEvents.php:66
-#: ../lib/GaletteEvents/PluginGaletteEvents.php:138
+#: ../lib/GaletteEvents/PluginGaletteEvents.php:69
+#: ../lib/GaletteEvents/PluginGaletteEvents.php:135
 msgid "Calendar"
 msgstr "Calendar"
 
-#: ../lib/GaletteEvents/PluginGaletteEvents.php:79
+#: ../lib/GaletteEvents/PluginGaletteEvents.php:75
 msgid "Bookings"
 msgstr "Bookings"
 
-#: ../lib/GaletteEvents/PluginGaletteEvents.php:159
+#: ../lib/GaletteEvents/PluginGaletteEvents.php:156
 msgid "New event booking"
 msgstr "New event booking"
 
-#: ../lib/GaletteEvents/PluginGaletteEvents.php:215
+#: ../lib/GaletteEvents/PluginGaletteEvents.php:212
 msgid "Upcoming events"
 msgstr "Upcoming events"
 
@@ -382,7 +417,7 @@ msgstr "Month calendar"
 msgid "Today"
 msgstr "Today"
 
-#: ../templates/default/calendar.html.twig:36
+#: ../templates/default/calendar.html.twig:33
 #: ../templates/default/bookings.html.twig:43
 msgid "New booking"
 msgstr "New booking"
@@ -584,7 +619,7 @@ msgstr "Inactive"
 msgid "No activity has been found"
 msgstr "No activity has been found"
 
-#: ../templates/default/event.html.twig:19
+#: ../templates/default/event.html.twig:17
 msgid "Is open"
 msgstr "Is open"
 
@@ -636,10 +671,6 @@ msgstr "Required"
 msgid "No activity available in the database."
 msgstr "No activity available in the database."
 
-#: ../templates/default/event.html.twig:179
-msgid "Please choose an activity to add"
-msgstr "Please choose an activity to add"
-
 #: ../templates/default/event.html.twig:186
 msgid "Please choose an activity to remove"
 msgstr "Please choose an activity to remove"
diff --git a/lib/GaletteEvents/Activity.php b/lib/GaletteEvents/Activity.php
index 62047e6a..49e57f52 100644
--- a/lib/GaletteEvents/Activity.php
+++ b/lib/GaletteEvents/Activity.php
@@ -200,7 +200,7 @@ public function store(): bool
 
             if (empty($this->id)) {
                 //we're inserting a new event
-                $this->creation_date = date("Y-m-d H:i:s");
+                $this->creation_date = date("Y-m-d");
                 $values['creation_date'] = $this->creation_date;
 
                 $insert = $this->zdb->insert($this->getTableName());
diff --git a/lib/GaletteEvents/Booking.php b/lib/GaletteEvents/Booking.php
index 07587d15..01fe5b7e 100644
--- a/lib/GaletteEvents/Booking.php
+++ b/lib/GaletteEvents/Booking.php
@@ -381,7 +381,7 @@ public function store(): bool
 
             if (empty($this->id)) {
                 //we're inserting a new event
-                $this->creation_date = date("Y-m-d H:i:s");
+                $this->creation_date = date("Y-m-d");
                 $values['creation_date'] = $this->creation_date;
 
                 $insert = $this->zdb->insert($this->getTableName());
diff --git a/lib/GaletteEvents/Event.php b/lib/GaletteEvents/Event.php
index b02a95c8..3a0bba4d 100644
--- a/lib/GaletteEvents/Event.php
+++ b/lib/GaletteEvents/Event.php
@@ -359,7 +359,7 @@ public function store(): bool
 
             if (empty($this->id)) {
                 //we're inserting a new event
-                $this->creation_date = date("Y-m-d H:i:s");
+                $this->creation_date = date("Y-m-d");
                 $values['creation_date'] = $this->creation_date;
 
                 $insert = $this->zdb->insert($this->getTableName());
diff --git a/lib/GaletteEvents/PluginEventProvider.php b/lib/GaletteEvents/PluginEventProvider.php
new file mode 100644
index 00000000..bd7ad767
--- /dev/null
+++ b/lib/GaletteEvents/PluginEventProvider.php
@@ -0,0 +1,89 @@
+<?php
+
+/**
+ * This file is part of Galette Events plugin (https://galette.eu).
+ * SPDX-FileCopyrightText: Copyright © 2018-2026 The Galette Team
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+declare(strict_types=1);
+
+namespace GaletteEvents;
+
+use Galette\Core\Db;
+use Galette\Entity\Group;
+use Galette\Events\GaletteEvent;
+use Laminas\Db\Sql\Expression;
+use League\Event\ListenerRegistry;
+use League\Event\ListenerSubscriber;
+use Psr\Container\ContainerInterface;
+
+/**
+ * Events listeners on core events
+ *
+ * @author Johan Cwiklinski <johan@x-tnd.be>
+ */
+class PluginEventProvider implements ListenerSubscriber
+{
+    /**
+     * Constructor
+     *
+     * Built while plugins are loaded: the database is resolved only
+     * when an event is emitted.
+     *
+     * @param ContainerInterface $container Container
+     */
+    public function __construct(private readonly ContainerInterface $container)
+    {
+    }
+
+    /**
+     * Set up listeners
+     *
+     * @param ListenerRegistry $acceptor Listener
+     */
+    public function subscribeListeners(ListenerRegistry $acceptor): void
+    {
+        $acceptor->subscribeTo(
+            'group.before_remove',
+            function (GaletteEvent $event): void {
+                /** @var Group $group */
+                $group = $event->getObject();
+                $count = $this->countGroupEvents((int)$group->getId());
+                if ($count > 0) {
+                    $group->preventRemoval(
+                        sprintf(
+                            _Tn(
+                                //TRANS: %1$s is the group name, %2$s the number of events
+                                'Group "%1$s" is used by %2$s event, it cannot be deleted. Remove the event or change its group first.',
+                                'Group "%1$s" is used by %2$s events, it cannot be deleted. Remove the events or change their group first.',
+                                $count,
+                                'events'
+                            ),
+                            $group->getName(),
+                            $count
+                        )
+                    );
+                }
+            }
+        );
+    }
+
+    /**
+     * Count events of a group
+     *
+     * Events restrict the removal of their group, which would otherwise
+     * make them visible to every member.
+     *
+     * @param int $group_id Group identifier
+     */
+    private function countGroupEvents(int $group_id): int
+    {
+        /** @var Db $zdb */
+        $zdb = $this->container->get(Db::class);
+        $select = $zdb->select(EVENTS_PREFIX . Event::TABLE);
+        $select->columns(['counter' => new Expression('COUNT(' . Event::PK . ')')]);
+        $select->where([Group::PK => $group_id]);
+        return (int)$zdb->execute($select)->current()->counter;
+    }
+}
diff --git a/lib/GaletteEvents/PluginGaletteEvents.php b/lib/GaletteEvents/PluginGaletteEvents.php
index 9cefa598..7320afa9 100644
--- a/lib/GaletteEvents/PluginGaletteEvents.php
+++ b/lib/GaletteEvents/PluginGaletteEvents.php
@@ -19,11 +19,14 @@
 use Galette\Core\Plugins\MenuProviderInterface;
 use Galette\Core\Plugins\NewsProviderInterface;
 use Galette\Entity\Adherent;
+use Galette\Entity\Group;
 use Galette\Core\GalettePlugin;
 use Galette\IO\News\Entry;
 use Galette\IO\News\Post;
 use GaletteEvents\Filters\EventsList;
 use GaletteEvents\Repository\Events;
+use Laminas\Db\Metadata\Object\ConstraintObject;
+use Laminas\Db\Metadata\Source\Factory;
 
 /**
  * Galette Events plugin
@@ -218,4 +221,28 @@ public function isInstalled(): bool
     {
         return $this->zdb->tableExists(EVENTS_PREFIX . Event::TABLE);
     }
+
+    /**
+     * Version of tables installed before plugins versions were recorded
+     *
+     * Since 1.1, amounts are no longer floating point numbers on PostgreSQL,
+     * and foreign keys are named on MySQL.
+     */
+    public function getLegacyDbVersion(): ?float
+    {
+        $metadata = Factory::createSourceFromAdapter($this->zdb->db);
+        if ($this->zdb->isPostgres()) {
+            $amount = $metadata->getColumn('payment_amount', PREFIX_DB . EVENTS_PREFIX . Booking::TABLE);
+            return $amount->getDataType() === 'real' ? 1.0 : null;
+        }
+
+        $table = PREFIX_DB . EVENTS_PREFIX . Event::TABLE;
+        /** @var ConstraintObject $constraint */
+        foreach ($metadata->getConstraints($table) as $constraint) {
+            if ($constraint->isForeignKey() && $constraint->getColumns() === [Group::PK]) {
+                return $constraint->getName() === $table . '_id_group_fkey' ? null : 1.0;
+            }
+        }
+        return null;
+    }
 }
diff --git a/scripts/mysql.sql b/scripts/mysql.sql
index 465b4bea..f49dcb40 100644
--- a/scripts/mysql.sql
+++ b/scripts/mysql.sql
@@ -26,8 +26,9 @@ CREATE TABLE galette_events_events (
   comment text,
   color varchar(7),
   PRIMARY KEY (id_event),
-  FOREIGN KEY (id_group) REFERENCES galette_groups (id_group) ON DELETE RESTRICT ON UPDATE CASCADE
-) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci;
+  CONSTRAINT galette_events_events_id_group_fkey FOREIGN KEY (id_group)
+    REFERENCES galette_groups (id_group) ON DELETE RESTRICT ON UPDATE CASCADE
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_520_ci;
 
 --
 -- Table structure for table `galette_events_bookings`
@@ -40,7 +41,7 @@ CREATE TABLE galette_events_bookings (
   id_adh int(10) unsigned NOT NULL,
   booking_date date NOT NULL default '1901-01-01',
   is_paid tinyint(1) NOT NULL default 0,
-  payment_amount  decimal(15, 2) default '0',
+  payment_amount decimal(15,2) default '0',
   payment_method tinyint(3) unsigned NOT NULL default '0',
   bank_name varchar(100) default NULL,
   check_number varchar(50) default NULL,
@@ -48,10 +49,12 @@ CREATE TABLE galette_events_bookings (
   creation_date date NOT NULL default '1901-01-01',
   comment text,
   PRIMARY KEY (id_booking),
-  UNIQUE KEY (id_event, id_adh),
-  FOREIGN KEY (id_event) REFERENCES galette_events_events (id_event) ON DELETE CASCADE ON UPDATE CASCADE,
-  FOREIGN KEY (id_adh) REFERENCES galette_adherents (id_adh) ON DELETE CASCADE ON UPDATE CASCADE
-) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci;
+  UNIQUE KEY galette_events_bookings_id_event_id_adh_key (id_event, id_adh),
+  CONSTRAINT galette_events_bookings_id_event_fkey FOREIGN KEY (id_event)
+    REFERENCES galette_events_events (id_event) ON DELETE CASCADE ON UPDATE CASCADE,
+  CONSTRAINT galette_events_bookings_id_adh_fkey FOREIGN KEY (id_adh)
+    REFERENCES galette_adherents (id_adh) ON DELETE CASCADE ON UPDATE CASCADE
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_520_ci;
 
 --
 -- Table structure for table `galette_events_activities`
@@ -65,28 +68,32 @@ CREATE TABLE galette_events_activities (
   creation_date date NOT NULL default '1901-01-01',
   comment text,
   PRIMARY KEY (id_activity)
-) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci;
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_520_ci;
 
 DROP TABLE IF EXISTS galette_events_activitiesevents;
 CREATE TABLE galette_events_activitiesevents (
   id_event int(10) NOT NULL,
   id_activity int(10) NOT NULL,
   status tinyint(1) NOT NULL,
-  PRIMARY KEY(id_event,id_activity),
-  FOREIGN KEY (id_event) REFERENCES galette_events_events (id_event) ON DELETE CASCADE ON UPDATE CASCADE,
-  FOREIGN KEY (id_activity) REFERENCES galette_events_activities (id_activity) ON DELETE CASCADE ON UPDATE CASCADE
-) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci;
+  PRIMARY KEY (id_event, id_activity),
+  CONSTRAINT galette_events_activitiesevents_id_event_fkey FOREIGN KEY (id_event)
+    REFERENCES galette_events_events (id_event) ON DELETE CASCADE ON UPDATE CASCADE,
+  CONSTRAINT galette_events_activitiesevents_id_activity_fkey FOREIGN KEY (id_activity)
+    REFERENCES galette_events_activities (id_activity) ON DELETE CASCADE ON UPDATE CASCADE
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_520_ci;
 
-DROP TABLE IF EXISTS galette_events_activitiesbookings CASCADE;
+DROP TABLE IF EXISTS galette_events_activitiesbookings;
 CREATE TABLE galette_events_activitiesbookings (
   id_activitybooking int(10) NOT NULL auto_increment,
   id_activity int(10) NOT NULL,
   id_booking int(10) NOT NULL,
-  checked tinyint(1) default 0,
+  checked tinyint(1) NOT NULL default 0,
   PRIMARY KEY (id_activitybooking),
-  UNIQUE KEY (id_activity, id_booking),
-  FOREIGN KEY (id_activity) REFERENCES galette_events_activities (id_activity) ON DELETE CASCADE ON UPDATE CASCADE,
-  FOREIGN KEY (id_booking) REFERENCES galette_events_bookings (id_booking) ON DELETE CASCADE ON UPDATE CASCADE
-);
+  UNIQUE KEY galette_events_activitiesbookings_id_activity_id_booking_key (id_activity, id_booking),
+  CONSTRAINT galette_events_activitiesbookings_id_activity_fkey FOREIGN KEY (id_activity)
+    REFERENCES galette_events_activities (id_activity) ON DELETE CASCADE ON UPDATE CASCADE,
+  CONSTRAINT galette_events_activitiesbookings_id_booking_fkey FOREIGN KEY (id_booking)
+    REFERENCES galette_events_bookings (id_booking) ON DELETE CASCADE ON UPDATE CASCADE
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_520_ci;
 
 SET FOREIGN_KEY_CHECKS=1;
diff --git a/scripts/pgsql.sql b/scripts/pgsql.sql
index 0d080798..7d3fc35c 100644
--- a/scripts/pgsql.sql
+++ b/scripts/pgsql.sql
@@ -23,7 +23,7 @@ CREATE TABLE galette_events_events (
   begin_date date default '19010101' NOT NULL,
   end_date date default '19010101' NOT NULL,
   creation_date date default '19010101' NOT NULL,
-  is_open boolean default TRUE,
+  is_open boolean default TRUE NOT NULL,
   id_group integer REFERENCES galette_groups(id_group) ON DELETE RESTRICT ON UPDATE CASCADE default NULL,
   comment text,
   color character varying(7),
@@ -45,11 +45,11 @@ CREATE SEQUENCE galette_events_bookings_id_seq
 DROP TABLE IF EXISTS galette_events_bookings CASCADE;
 CREATE TABLE galette_events_bookings (
   id_booking integer DEFAULT nextval('galette_events_bookings_id_seq'::text) NOT NULL,
-  id_event integer REFERENCES galette_events_events (id_event) ON DELETE CASCADE ON UPDATE CASCADE,
-  id_adh integer REFERENCES galette_adherents (id_adh) ON DELETE CASCADE ON UPDATE CASCADE,
+  id_event integer NOT NULL REFERENCES galette_events_events (id_event) ON DELETE CASCADE ON UPDATE CASCADE,
+  id_adh integer NOT NULL REFERENCES galette_adherents (id_adh) ON DELETE CASCADE ON UPDATE CASCADE,
   booking_date date default '19010101' NOT NULL,
-  is_paid boolean default FALSE,
-  payment_amount real default '0',
+  is_paid boolean default FALSE NOT NULL,
+  payment_amount numeric(15,2) default '0',
   payment_method smallint default '0' NOT NULL,
   bank_name character varying(100) default NULL,
   check_number character varying(50) default NULL,
@@ -76,7 +76,7 @@ DROP TABLE IF EXISTS galette_events_activities CASCADE;
 CREATE TABLE galette_events_activities (
   id_activity integer DEFAULT nextval('galette_events_activities_id_seq'::text) NOT NULL,
   name character varying(150) NOT NULL,
-  is_active boolean default TRUE,
+  is_active boolean default TRUE NOT NULL,
   creation_date date default '19010101' NOT NULL,
   comment text,
   PRIMARY KEY (id_activity)
@@ -101,9 +101,9 @@ CREATE SEQUENCE galette_events_activitiesbookings_id_seq
 DROP TABLE IF EXISTS galette_events_activitiesbookings CASCADE;
 CREATE TABLE galette_events_activitiesbookings (
   id_activitybooking integer DEFAULT nextval('galette_events_activitiesbookings_id_seq'::text) NOT NULL,
-  id_activity integer REFERENCES galette_events_activities (id_activity) ON DELETE CASCADE ON UPDATE CASCADE,
-  id_booking integer REFERENCES galette_events_bookings (id_booking) ON DELETE CASCADE ON UPDATE CASCADE,
-  checked boolean default FALSE,
+  id_activity integer NOT NULL REFERENCES galette_events_activities (id_activity) ON DELETE CASCADE ON UPDATE CASCADE,
+  id_booking integer NOT NULL REFERENCES galette_events_bookings (id_booking) ON DELETE CASCADE ON UPDATE CASCADE,
+  checked boolean default FALSE NOT NULL,
   PRIMARY KEY (id_activitybooking),
   UNIQUE (id_activity, id_booking)
 );
diff --git a/scripts/upgrade-to-1.1-mysql.sql b/scripts/upgrade-to-1.1-mysql.sql
new file mode 100644
index 00000000..a022f00c
--- /dev/null
+++ b/scripts/upgrade-to-1.1-mysql.sql
@@ -0,0 +1,125 @@
+--
+-- This file is part of Galette Events plugin (https://galette.eu).
+-- SPDX-FileCopyrightText: Copyright © 2018-2026 The Galette Team
+-- SPDX-License-Identifier: GPL-3.0-or-later
+--
+
+-- Align schema with PostgreSQL one: utf8mb4, named foreign keys.
+-- Foreign keys names depend on the MySQL version that created them, and
+-- MySQL cannot drop them conditionally: tables holding some are rebuilt.
+SET FOREIGN_KEY_CHECKS=0;
+
+ALTER TABLE galette_events_activities CONVERT TO CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_520_ci;
+-- Conversion turns text into mediumtext to keep its capacity in bytes
+ALTER TABLE galette_events_activities MODIFY comment text;
+
+CREATE TABLE galette_events_events_new (
+  id_event int(10) NOT NULL auto_increment,
+  name varchar(150) NOT NULL,
+  address varchar(150) NOT NULL default '',
+  zip varchar(10) NOT NULL default '',
+  town varchar(50) NOT NULL default '',
+  country varchar(50) default NULL,
+  begin_date date NOT NULL default '1901-01-01',
+  end_date date NOT NULL default '1901-01-01',
+  creation_date date NOT NULL default '1901-01-01',
+  is_open tinyint(1) NOT NULL default 1,
+  id_group int unsigned default NULL,
+  comment text,
+  color varchar(7),
+  PRIMARY KEY (id_event),
+  CONSTRAINT galette_events_events_id_group_fkey FOREIGN KEY (id_group)
+    REFERENCES galette_groups (id_group) ON DELETE RESTRICT ON UPDATE CASCADE
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_520_ci;
+
+INSERT INTO galette_events_events_new
+  (id_event, name, address, zip, town, country, begin_date, end_date, creation_date,
+    is_open, id_group, comment)
+SELECT id_event, name, address, zip, town, country, begin_date, end_date, creation_date,
+    is_open, id_group, comment
+FROM galette_events_events;
+
+-- Color came with 2.1.0, but its update script never ran: installations
+-- created before do not have the column.
+SET @events_color = (
+  SELECT IF(
+    COUNT(*) > 0,
+    'UPDATE galette_events_events_new n INNER JOIN galette_events_events o ON o.id_event = n.id_event SET n.color = o.color',
+    'DO 0'
+  )
+  FROM information_schema.COLUMNS
+  WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = 'galette_events_events' AND COLUMN_NAME = 'color'
+);
+PREPARE events_color FROM @events_color;
+EXECUTE events_color;
+DEALLOCATE PREPARE events_color;
+
+CREATE TABLE galette_events_bookings_new (
+  id_booking int(10) NOT NULL auto_increment,
+  id_event int(10) NOT NULL,
+  id_adh int(10) unsigned NOT NULL,
+  booking_date date NOT NULL default '1901-01-01',
+  is_paid tinyint(1) NOT NULL default 0,
+  payment_amount decimal(15,2) default '0',
+  payment_method tinyint(3) unsigned NOT NULL default '0',
+  bank_name varchar(100) default NULL,
+  check_number varchar(50) default NULL,
+  number_people int(4) default NULL,
+  creation_date date NOT NULL default '1901-01-01',
+  comment text,
+  PRIMARY KEY (id_booking),
+  UNIQUE KEY galette_events_bookings_id_event_id_adh_key (id_event, id_adh),
+  CONSTRAINT galette_events_bookings_id_event_fkey FOREIGN KEY (id_event)
+    REFERENCES galette_events_events (id_event) ON DELETE CASCADE ON UPDATE CASCADE,
+  CONSTRAINT galette_events_bookings_id_adh_fkey FOREIGN KEY (id_adh)
+    REFERENCES galette_adherents (id_adh) ON DELETE CASCADE ON UPDATE CASCADE
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_520_ci;
+
+INSERT INTO galette_events_bookings_new
+  (id_booking, id_event, id_adh, booking_date, is_paid, payment_amount, payment_method,
+    bank_name, check_number, number_people, creation_date, comment)
+SELECT id_booking, id_event, id_adh, booking_date, is_paid, payment_amount, payment_method,
+    bank_name, check_number, number_people, creation_date, comment
+FROM galette_events_bookings;
+
+CREATE TABLE galette_events_activitiesevents_new (
+  id_event int(10) NOT NULL,
+  id_activity int(10) NOT NULL,
+  status tinyint(1) NOT NULL,
+  PRIMARY KEY (id_event, id_activity),
+  CONSTRAINT galette_events_activitiesevents_id_event_fkey FOREIGN KEY (id_event)
+    REFERENCES galette_events_events (id_event) ON DELETE CASCADE ON UPDATE CASCADE,
+  CONSTRAINT galette_events_activitiesevents_id_activity_fkey FOREIGN KEY (id_activity)
+    REFERENCES galette_events_activities (id_activity) ON DELETE CASCADE ON UPDATE CASCADE
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_520_ci;
+
+INSERT INTO galette_events_activitiesevents_new (id_event, id_activity, status)
+SELECT id_event, id_activity, status
+FROM galette_events_activitiesevents;
+
+CREATE TABLE galette_events_activitiesbookings_new (
+  id_activitybooking int(10) NOT NULL auto_increment,
+  id_activity int(10) NOT NULL,
+  id_booking int(10) NOT NULL,
+  checked tinyint(1) NOT NULL default 0,
+  PRIMARY KEY (id_activitybooking),
+  UNIQUE KEY galette_events_activitiesbookings_id_activity_id_booking_key (id_activity, id_booking),
+  CONSTRAINT galette_events_activitiesbookings_id_activity_fkey FOREIGN KEY (id_activity)
+    REFERENCES galette_events_activities (id_activity) ON DELETE CASCADE ON UPDATE CASCADE,
+  CONSTRAINT galette_events_activitiesbookings_id_booking_fkey FOREIGN KEY (id_booking)
+    REFERENCES galette_events_bookings (id_booking) ON DELETE CASCADE ON UPDATE CASCADE
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_520_ci;
+
+INSERT INTO galette_events_activitiesbookings_new (id_activitybooking, id_activity, id_booking, checked)
+SELECT id_activitybooking, id_activity, id_booking, COALESCE(checked, 0)
+FROM galette_events_activitiesbookings;
+
+DROP TABLE galette_events_activitiesbookings, galette_events_activitiesevents,
+  galette_events_bookings, galette_events_events;
+
+RENAME TABLE galette_events_events_new TO galette_events_events,
+  galette_events_bookings_new TO galette_events_bookings,
+  galette_events_activitiesevents_new TO galette_events_activitiesevents,
+  galette_events_activitiesbookings_new TO galette_events_activitiesbookings;
+
+SET FOREIGN_KEY_CHECKS=1;
diff --git a/scripts/upgrade-to-1.1-pgsql.sql b/scripts/upgrade-to-1.1-pgsql.sql
new file mode 100644
index 00000000..22e9d80b
--- /dev/null
+++ b/scripts/upgrade-to-1.1-pgsql.sql
@@ -0,0 +1,34 @@
+--
+-- This file is part of Galette Events plugin (https://galette.eu).
+-- SPDX-FileCopyrightText: Copyright © 2018-2026 The Galette Team
+-- SPDX-License-Identifier: GPL-3.0-or-later
+--
+
+-- Color came with 2.1.0, but its update script never ran: installations
+-- created before do not have the column.
+ALTER TABLE galette_events_events ADD COLUMN IF NOT EXISTS color character varying(7);
+
+-- Amounts were stored as floating point numbers
+ALTER TABLE galette_events_bookings
+  ALTER COLUMN payment_amount TYPE numeric(15,2) USING ROUND(CAST(payment_amount AS numeric), 2),
+  ALTER COLUMN payment_amount SET DEFAULT '0';
+
+-- A booking always has an event and a member, a booked activity an activity and a booking
+DELETE FROM galette_events_bookings WHERE id_event IS NULL OR id_adh IS NULL;
+DELETE FROM galette_events_activitiesbookings WHERE id_activity IS NULL OR id_booking IS NULL;
+ALTER TABLE galette_events_bookings
+  ALTER COLUMN id_event SET NOT NULL,
+  ALTER COLUMN id_adh SET NOT NULL;
+ALTER TABLE galette_events_activitiesbookings
+  ALTER COLUMN id_activity SET NOT NULL,
+  ALTER COLUMN id_booking SET NOT NULL;
+
+-- Flags are never unknown, as on MySQL
+UPDATE galette_events_events SET is_open = TRUE WHERE is_open IS NULL;
+ALTER TABLE galette_events_events ALTER COLUMN is_open SET NOT NULL;
+UPDATE galette_events_bookings SET is_paid = FALSE WHERE is_paid IS NULL;
+ALTER TABLE galette_events_bookings ALTER COLUMN is_paid SET NOT NULL;
+UPDATE galette_events_activities SET is_active = TRUE WHERE is_active IS NULL;
+ALTER TABLE galette_events_activities ALTER COLUMN is_active SET NOT NULL;
+UPDATE galette_events_activitiesbookings SET checked = FALSE WHERE checked IS NULL;
+ALTER TABLE galette_events_activitiesbookings ALTER COLUMN checked SET NOT NULL;
diff --git a/scripts/upgrade-to-2.0-mysql.sql b/scripts/upgrade-to-2.0-mysql.sql
deleted file mode 100644
index 4b6becac..00000000
--- a/scripts/upgrade-to-2.0-mysql.sql
+++ /dev/null
@@ -1,7 +0,0 @@
---
--- This file is part of Galette Events plugin (https://galette.eu).
--- SPDX-FileCopyrightText: Copyright © 2018-2026 The Galette Team
--- SPDX-License-Identifier: GPL-3.0-or-later
---
-
-ALTER TABLE galette_events_events ADD `color` varchar(7);
diff --git a/scripts/upgrade-to-2.0-pgsql.sql b/scripts/upgrade-to-2.0-pgsql.sql
deleted file mode 100644
index 2638d370..00000000
--- a/scripts/upgrade-to-2.0-pgsql.sql
+++ /dev/null
@@ -1,7 +0,0 @@
---
--- This file is part of Galette Events plugin (https://galette.eu).
--- SPDX-FileCopyrightText: Copyright © 2018-2026 The Galette Team
--- SPDX-License-Identifier: GPL-3.0-or-later
---
-
-ALTER TABLE galette_events_events ADD COLUMN color character varying(7);
diff --git a/tests/GaletteEvents/tests/units/Activity.php b/tests/GaletteEvents/tests/units/Activity.php
index 0d6eb03e..668aa59c 100644
--- a/tests/GaletteEvents/tests/units/Activity.php
+++ b/tests/GaletteEvents/tests/units/Activity.php
@@ -79,6 +79,8 @@ public function testCrud(): void
         $this->assertTrue($activity->store());
         $first_id = $activity->getId();
         $this->assertGreaterThan(0, $first_id);
+        //creation date column holds no time
+        $this->assertSame(date('Y-m-d'), $activity->getCreationDate(false));
 
         $this->assertTrue($activity->load($first_id));
         $this->assertSame('Test activity', $activity->getName());
diff --git a/tests/GaletteEvents/tests/units/PluginEventProvider.php b/tests/GaletteEvents/tests/units/PluginEventProvider.php
new file mode 100644
index 00000000..f946cf77
--- /dev/null
+++ b/tests/GaletteEvents/tests/units/PluginEventProvider.php
@@ -0,0 +1,104 @@
+<?php
+
+/**
+ * This file is part of Galette Events plugin (https://galette.eu).
+ * SPDX-FileCopyrightText: Copyright © 2018-2026 The Galette Team
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+declare(strict_types=1);
+
+namespace GaletteEvents\tests\units;
+
+use Galette\Entity\Group;
+use Galette\Tests\GaletteRoutingTestCase;
+use GaletteEvents\tests\EventsFixtures;
+
+/**
+ * Listeners on core events tests
+ *
+ * @author Johan Cwiklinski <johan@x-tnd.be>
+ */
+class PluginEventProvider extends GaletteRoutingTestCase
+{
+    use EventsFixtures;
+
+    protected int $seed = 20260927101512;
+    protected bool $load_plugins = true;
+
+    /**
+     * Cleanup after each test method
+     */
+    public function tearDown(): void
+    {
+        $this->login->logout();
+        $this->cleanEvents();
+        parent::tearDown();
+    }
+
+    /**
+     * Remove a group from core route
+     *
+     * @param int $group_id Group ID
+     */
+    private function removeGroup(int $group_id): void
+    {
+        $this->logSuperAdmin();
+        $request = $this->createRequest('doRemoveGroup', ['id' => (string)$group_id], 'POST');
+        $request = $request->withParsedBody(['id' => (string)$group_id, 'confirm' => true, 'cascade' => true]);
+        $response = $this->app->handle($request);
+        $this->login->logout();
+        $this->assertSame(301, $response->getStatusCode());
+    }
+
+    /**
+     * Test a group holding events cannot be removed
+     */
+    public function testGroupWithEventsIsNotRemoved(): void
+    {
+        global $zdb;
+        $zdb = $this->zdb;
+
+        $group = $this->createGroup('Jedi');
+        $group_id = $group->getId();
+        $this->insertEvent('Council', ['id_group' => $group_id]);
+        $this->insertEvent('Training', ['id_group' => $group_id]);
+        $this->insertEvent('Public event');
+
+        $this->removeGroup($group_id);
+        $message = 'Group "Jedi" is used by 2 events, it cannot be deleted. Remove the events or change their group first.';
+        $this->expectLogEntry(\Analog\Analog::WARNING, 'Group "Jedi" cannot be removed: ' . $message);
+        $this->expectFlashData(['error_detected' => [$message]]);
+        $this->assertTrue((new Group())->load($group_id));
+
+        //a subgroup holding an event prevents cascade removal of its parent
+        $parent = $this->createGroup('Order');
+        $group->setParentGroup($parent->getId());
+        $this->assertTrue($group->store());
+        $this->zdb->execute(
+            $this->zdb->delete(EVENTS_PREFIX . \GaletteEvents\Event::TABLE)->where(['name' => 'Training'])
+        );
+
+        $this->removeGroup($parent->getId());
+        $message = 'Group "Jedi" is used by 1 event, it cannot be deleted. Remove the event or change its group first.';
+        $this->expectLogEntry(\Analog\Analog::WARNING, 'Group "Order" cannot be removed: ' . $message);
+        $this->expectFlashData(['error_detected' => [$message]]);
+        $this->assertTrue((new Group())->load($parent->getId()));
+    }
+
+    /**
+     * Test a group without events is removed
+     */
+    public function testGroupWithoutEventsIsRemoved(): void
+    {
+        global $zdb;
+        $zdb = $this->zdb;
+
+        $group_id = $this->createGroup('Sith')->getId();
+        $this->insertEvent('Public event');
+
+        $this->removeGroup($group_id);
+        $this->expectFlashData(['success_detected' => ['Successfully deleted!']]);
+        $this->assertFalse((new Group())->load($group_id));
+    }
+}
diff --git a/tests/GaletteEvents/tests/units/PluginGaletteEvents.php b/tests/GaletteEvents/tests/units/PluginGaletteEvents.php
index ed229455..67e2c03d 100644
--- a/tests/GaletteEvents/tests/units/PluginGaletteEvents.php
+++ b/tests/GaletteEvents/tests/units/PluginGaletteEvents.php
@@ -146,4 +146,12 @@ public function testIsInstalled(): void
     {
         $this->assertTrue($this->getPlugin()->isInstalled());
     }
+
+    /**
+     * Test tables installed from current scripts are not taken for legacy ones
+     */
+    public function testGetLegacyDbVersion(): void
+    {
+        $this->assertNull($this->getPlugin()->getLegacyDbVersion());
+    }
 }