diff --git a/build.gradle b/build.gradle
index d6a397d..bbe3222 100644
--- a/build.gradle
+++ b/build.gradle
@@ -90,6 +90,7 @@ kotlin {
                 implementation "io.ktor:ktor-client-apache:$ktor_version"
 
                 implementation 'org.xerial:sqlite-jdbc:3.25.2'
+                api 'mysql:mysql-connector-java:8.0.16'
                 implementation 'org.jetbrains.exposed:exposed:0.12.2'
 
                 implementation 'org.mindrot:jbcrypt:0.4'
diff --git a/portal.toml b/portal.toml
index 74ecea1..9236ca5 100644
--- a/portal.toml
+++ b/portal.toml
@@ -18,3 +18,9 @@ wiki_url = "https://wiki.kif.rocks/w/index.php?title=KIF470:Arbeitskreise&action
 
 [twitter]
 timeline = "https://twitter.com/kiforbiter?ref_src=twsrc%5Etfw"
+
+[database]
+type = "sqlite"
+url = ""
+username = ""
+password = ""
diff --git a/src/jsMain/kotlin/de/kif/frontend/main.kt b/src/jsMain/kotlin/de/kif/frontend/main.kt
index aa72d9c..2e59890 100644
--- a/src/jsMain/kotlin/de/kif/frontend/main.kt
+++ b/src/jsMain/kotlin/de/kif/frontend/main.kt
@@ -1,5 +1,8 @@
 package de.kif.frontend
 
+import de.kif.frontend.repository.RoomRepository
+import de.kif.frontend.repository.ScheduleRepository
+import de.kif.frontend.repository.WorkGroupRepository
 import de.kif.frontend.views.board.initBoard
 import de.kif.frontend.views.calendar.initCalendar
 import de.kif.frontend.views.initAnnouncement
@@ -61,4 +64,35 @@ fun main() = init {
             }
         }
     }
+
+    val url = window.location.pathname
+    if ("brett" in url || "wand" in url) {
+        ScheduleRepository.onCreate {
+            window.location.reload()
+        }
+        ScheduleRepository.onUpdate {
+            window.location.reload()
+        }
+        ScheduleRepository.onDelete {
+            window.location.reload()
+        }
+        RoomRepository.onCreate {
+            window.location.reload()
+        }
+        RoomRepository.onUpdate {
+            window.location.reload()
+        }
+        RoomRepository.onDelete {
+            window.location.reload()
+        }
+        WorkGroupRepository.onCreate {
+            window.location.reload()
+        }
+        WorkGroupRepository.onUpdate {
+            window.location.reload()
+        }
+        WorkGroupRepository.onDelete {
+            window.location.reload()
+        }
+    }
 }
diff --git a/src/jsMain/kotlin/de/kif/frontend/views/calendar/Calendar.kt b/src/jsMain/kotlin/de/kif/frontend/views/calendar/Calendar.kt
index c049313..ec63b6b 100644
--- a/src/jsMain/kotlin/de/kif/frontend/views/calendar/Calendar.kt
+++ b/src/jsMain/kotlin/de/kif/frontend/views/calendar/Calendar.kt
@@ -26,11 +26,12 @@ class Calendar(calendar: HTMLElement) : View(calendar) {
 
     private val htmlBody = document.body ?: createHtmlView()
 
-    val day = (calendarTable.dataset["day"]?.toIntOrNull() ?: -1).also { println(it) }
-    val reloadOnFinish = (calendarTable.dataset["reload"]?.toBoolean() ?: false).also { println(it) }
-    val referenceDate = (calendarTable.dataset["reference"]?.toLongOrNull() ?: -1L).also { println(it) }
-    val nowDate = (calendarTable.dataset["now"]?.toLongOrNull() ?: -1L).also { println(it) }
-    val timeDifference = (Date.now().toLong() - nowDate).also { println(it) }
+    val day = (calendarTable.dataset["day"]?.toIntOrNull() ?: -1)
+    val reloadOnFinish = (calendarTable.dataset["reload"]?.toBoolean() ?: false)
+    val hideEmpty = (calendarTable.dataset["hide-empty"]?.toBoolean() ?: false)
+    val referenceDate = (calendarTable.dataset["reference"]?.toLongOrNull() ?: -1L)
+    val nowDate = (calendarTable.dataset["now"]?.toLongOrNull() ?: -1L)
+    val timeDifference = (Date.now().toLong() - nowDate)
 
     fun scrollVerticalBy(pixel: Double, scrollBehavior: ScrollBehavior = ScrollBehavior.SMOOTH) {
         scrollAllVerticalBy(pixel, scrollBehavior)
diff --git a/src/jsMain/kotlin/de/kif/frontend/views/calendar/CalendarBody.kt b/src/jsMain/kotlin/de/kif/frontend/views/calendar/CalendarBody.kt
index 5c34148..a66b0d3 100644
--- a/src/jsMain/kotlin/de/kif/frontend/views/calendar/CalendarBody.kt
+++ b/src/jsMain/kotlin/de/kif/frontend/views/calendar/CalendarBody.kt
@@ -74,18 +74,12 @@ class CalendarBody(val calendar: Calendar, view: HTMLElement) : ViewCollection<C
         min = (min / 60 - 1) * 60
         max = (max / 60 + 2) * 60
 
-        if (min == minTime && max == maxTime) return
-
         minTime = min
         maxTime = max
 
         min = calendarBodies.map { it.minTime }.min() ?: min
         max = calendarBodies.map { it.maxTime }.max() ?: max
 
-        calendarBodies.filter { it != this }.forEach {
-            it.updateRows()
-        }
-
         while (isNotEmpty() && min > first().time) {
             remove(first())
         }
diff --git a/src/jsMain/kotlin/de/kif/frontend/views/calendar/CalendarRow.kt b/src/jsMain/kotlin/de/kif/frontend/views/calendar/CalendarRow.kt
index 6d84a17..dde5910 100644
--- a/src/jsMain/kotlin/de/kif/frontend/views/calendar/CalendarRow.kt
+++ b/src/jsMain/kotlin/de/kif/frontend/views/calendar/CalendarRow.kt
@@ -8,7 +8,7 @@ import org.w3c.dom.HTMLElement
 import org.w3c.dom.HTMLSpanElement
 import org.w3c.dom.set
 
-class CalendarRow(calendar: CalendarBody, view: HTMLElement) : ViewCollection<CalendarCell>(view) {
+class CalendarRow(val calendar: CalendarBody, view: HTMLElement) : ViewCollection<CalendarCell>(view) {
     val day = calendar.day
 
     val time = dataset["time"]?.toIntOrNull() ?: 0
@@ -49,8 +49,6 @@ class CalendarRow(calendar: CalendarBody, view: HTMLElement) : ViewCollection<Ca
             }
             row.html.appendChild(rowHeader)
 
-            row.html
-
             val rooms = RoomRepository.all()
 
             for (room in rooms) {
diff --git a/src/jsMain/resources/style/components/_calendar.scss b/src/jsMain/resources/style/components/_calendar.scss
index 09b1830..3e9d325 100644
--- a/src/jsMain/resources/style/components/_calendar.scss
+++ b/src/jsMain/resources/style/components/_calendar.scss
@@ -169,6 +169,10 @@
   background-color: var(--table-header-color) !important;
 }
 
+.calendar-cell[data-empty = "true"] {
+  display: none;
+}
+
 .calendar-tools {
   position: absolute;
   top: -5rem;
diff --git a/src/jvmMain/kotlin/de/kif/backend/Configuration.kt b/src/jvmMain/kotlin/de/kif/backend/Configuration.kt
index 8bc2773..d29cf67 100644
--- a/src/jvmMain/kotlin/de/kif/backend/Configuration.kt
+++ b/src/jvmMain/kotlin/de/kif/backend/Configuration.kt
@@ -133,6 +133,20 @@ object Configuration {
         val time by c(ResoSpec.time)
     }
 
+    private object DatabaseSpec : ConfigSpec("database") {
+        val type by required<String>()
+        val url by required<String>()
+        val username by required<String>()
+        val password by required<String>()
+    }
+
+    object Database {
+        val type by c(DatabaseSpec.type)
+        val url by c(DatabaseSpec.url)
+        val username by c(DatabaseSpec.username)
+        val password by c(DatabaseSpec.password)
+    }
+
     init {
         var config = Config {
             addSpec(ServerSpec)
@@ -142,6 +156,7 @@ object Configuration {
             addSpec(GeneralSpec)
             addSpec(TwitterSpec)
             addSpec(ResoSpec)
+            addSpec(DatabaseSpec)
         }.from.toml.resource("portal.toml")
 
         for (file in Files.list(Paths.get("."))) {
diff --git a/src/jvmMain/kotlin/de/kif/backend/database/Connection.kt b/src/jvmMain/kotlin/de/kif/backend/database/Connection.kt
index f4272be..d56496e 100644
--- a/src/jvmMain/kotlin/de/kif/backend/database/Connection.kt
+++ b/src/jvmMain/kotlin/de/kif/backend/database/Connection.kt
@@ -26,14 +26,39 @@ object Connection {
     )
 
     fun init() {
-        val dbPath = Configuration.Path.databasePath.toString()
-        Database.connect("jdbc:sqlite:$dbPath", "org.sqlite.JDBC")
+        val type = Configuration.Database.type
+        val url = Configuration.Database.url
+        val username = Configuration.Database.username
+        val password = Configuration.Database.password
+        when (type) {
+            "mysql" -> {
+                Database.connect(
+                    "jdbc:mysql://$url:3306/akplan?user=$username&password=$password&serverTimezone=UTC",
+                    "com.mysql.cj.jdbc.Driver",
+                    username,
+                    password
+                )
+            }
+            "mariadb" -> {
+                Database.connect(
+                    "jdbc:mariadb://$url:3306/akplan?user=$username&password=$password&serverTimezone=UTC",
+                    "org.mariadb.jdbc.Driver",
+                    username,
+                    password
+                )
+            }
+            else -> {
+                val dbPath = Configuration.Path.databasePath.toString()
+                Database.connect("jdbc:sqlite:$dbPath", "org.sqlite.JDBC")
+            }
+        }
+
         TransactionManager.manager.defaultIsolationLevel = TRANSACTION_SERIALIZABLE
 
         try {
             create()
         } catch (e: ExposedSQLException) {
-            logger.error { "Cannot initialize the database!" }
+            logger.error(e) { "Cannot initialize the database!" }
 
             print("Do you want to recreate the database (you will lose all data)? [y/N]: ")
             val result = readLine()
diff --git a/src/jvmMain/kotlin/de/kif/backend/database/Schema.kt b/src/jvmMain/kotlin/de/kif/backend/database/Schema.kt
index 0b997b1..2b8604e 100644
--- a/src/jvmMain/kotlin/de/kif/backend/database/Schema.kt
+++ b/src/jvmMain/kotlin/de/kif/backend/database/Schema.kt
@@ -29,7 +29,7 @@ object DbWorkGroup : Table() {
     val accessible = bool("accessible")
 
     val language = enumeration("language", Language::class)
-    val leader = text("leader").default("[]")
+    val leader = text("leader")
 
     val length = integer("length")
     val constraints = text("constraints")
@@ -49,9 +49,9 @@ object DbRoom : Table() {
     val whiteboard = bool("whiteboard")
     val blackboard = bool("blackboard")
     val accessible = bool("accessible")
-    val pool = bool("pool").default(false)
+    val pool = bool("pool")
 
-    val blocked = text("blocked").default("[]")
+    val blocked = text("blocked")
 
     val createdAt = long("createdAt")
     val updatedAt = long("updatedAt")
@@ -63,8 +63,8 @@ object DbSchedule : Table() {
     val roomId = long("room_id").index()
     val day = integer("day").index()
     val time = integer("time_slot")
-    val lockRoom = bool("lock_room").default(false)
-    val lockTime = bool("lock_time").default(false)
+    val lockRoom = bool("lock_room")
+    val lockTime = bool("lock_time")
 
     val createdAt = long("createdAt")
     val updatedAt = long("updatedAt")
diff --git a/src/jvmMain/kotlin/de/kif/backend/route/Account.kt b/src/jvmMain/kotlin/de/kif/backend/route/Account.kt
index 95ae47c..cbe92e3 100644
--- a/src/jvmMain/kotlin/de/kif/backend/route/Account.kt
+++ b/src/jvmMain/kotlin/de/kif/backend/route/Account.kt
@@ -6,10 +6,12 @@ import de.kif.backend.prefix
 import de.kif.backend.repository.*
 import de.kif.backend.route.api.error
 import de.kif.backend.util.Backup
+import de.kif.backend.util.PushService
 import de.kif.backend.util.WikiImporter
 import de.kif.backend.view.respondMain
 import de.kif.common.RepositoryType
 import de.kif.common.model.Permission
+import de.kif.common.model.Post
 import io.ktor.application.call
 import io.ktor.http.ContentType
 import io.ktor.http.HttpStatusCode
@@ -51,6 +53,10 @@ fun Route.account() {
                         +"Sicherung"
                     }
 
+                    a(href = "$prefix/account/reload", classes = "form-btn") {
+                        +"Alle Geräte neu laden"
+                    }
+
                     if (user.checkPermission(Permission.SCHEDULE)) {
                         a(href = "$prefix/account/import", classes = "form-btn") {
                             +"Aus Wiki importieren"
@@ -516,4 +522,8 @@ fun Route.account() {
             call.error(HttpStatusCode.Unauthorized)
         }
     }
+    get("/account/reload") {
+        PushService.signature = Post.generateUrl()
+        call.respondRedirect("$prefix/account")
+    }
 }
diff --git a/src/jvmMain/kotlin/de/kif/backend/route/Board.kt b/src/jvmMain/kotlin/de/kif/backend/route/Board.kt
index 6a92f63..050565d 100644
--- a/src/jvmMain/kotlin/de/kif/backend/route/Board.kt
+++ b/src/jvmMain/kotlin/de/kif/backend/route/Board.kt
@@ -175,7 +175,8 @@ fun Route.board() {
                                 max,
                                 rooms,
                                 schedules,
-                                reloadAfterFinish = true
+                                reloadAfterFinish = true,
+                                hideEmptyRooms = true
                             )
                         }
                         div("board-twitter") {
diff --git a/src/jvmMain/kotlin/de/kif/backend/route/Calendar.kt b/src/jvmMain/kotlin/de/kif/backend/route/Calendar.kt
index e7b351e..e4f02de 100644
--- a/src/jvmMain/kotlin/de/kif/backend/route/Calendar.kt
+++ b/src/jvmMain/kotlin/de/kif/backend/route/Calendar.kt
@@ -72,7 +72,8 @@ fun DIV.renderCalendar(
     to: Int,
     rooms: List<Room>,
     schedules: Map<Room, Map<Int, List<Schedule>>>,
-    reloadAfterFinish: Boolean = false
+    reloadAfterFinish: Boolean = false,
+    hideEmptyRooms: Boolean = false
 ) {
     val gridLabelWidth = 60
     val minutesOfDay = to - from
@@ -91,6 +92,7 @@ fun DIV.renderCalendar(
         attributes["data-reference"] = Configuration.Schedule.referenceDate.time.toString()
         attributes["data-now"] = now.timeInMillis.toString()
         attributes["data-reload"] = reloadAfterFinish.toString()
+        attributes["data-hide-empty"] = hideEmptyRooms.toString()
 
         div("calendar-table-box ${orientation.name.toLowerCase().replace("_", "-")}") {
             div("calendar-header") {
@@ -103,6 +105,7 @@ fun DIV.renderCalendar(
                 for (room in rooms) {
                     div("calendar-cell") {
                         attributes["data-room"] = room.id.toString()
+                        attributes["data-empty"] = (hideEmptyRooms && room !in schedules).toString()
 
                         span {
                             +room.name
@@ -147,6 +150,7 @@ fun DIV.renderCalendar(
                             div("calendar-cell") {
                                 attributes["data-room"] = room.id.toString()
                                 attributes["data-blocked"] = blocked.toString()
+                                attributes["data-empty"] = (hideEmptyRooms && room !in schedules).toString()
 
                                 title = room.name + " - " + timeString
 
diff --git a/src/jvmMain/kotlin/de/kif/backend/route/Wall.kt b/src/jvmMain/kotlin/de/kif/backend/route/Wall.kt
index 25c48e0..5dc6b73 100644
--- a/src/jvmMain/kotlin/de/kif/backend/route/Wall.kt
+++ b/src/jvmMain/kotlin/de/kif/backend/route/Wall.kt
@@ -1,11 +1,11 @@
 package de.kif.backend.route
 
-import com.soywiz.klock.*
-import com.soywiz.klock.locale.german
 import de.kif.backend.Configuration
 import de.kif.backend.repository.RoomRepository
 import de.kif.backend.repository.ScheduleRepository
 import de.kif.backend.view.respondMain
+import de.kif.common.formatDate
+import de.kif.common.formatDateWithoutYear
 import de.kif.common.model.Room
 import de.kif.common.model.Schedule
 import io.ktor.routing.Route
@@ -63,6 +63,8 @@ fun Route.wall() {
             wallStart + 2
         ).map { genWallData(it) }
 
+        val rooms = RoomRepository.all()
+
         var min = days.mapNotNull { it.min }.min() ?: 12 * 60
         val max = days.mapNotNull { it.max }.max() ?: 12 * 60
 
@@ -70,18 +72,15 @@ fun Route.wall() {
             min = max
         }
 
-        val refDate = DateTime(Configuration.Schedule.referenceDate.time)
+        val refDate = Configuration.Schedule.referenceDate.time
 
         respondMain(true, true) {
             content {
                 div("wall") {
                     for (day in days) {
 
-                        val date = refDate + day.number.days
-                        val dateString = DateFormat("EEEE, d. MMMM")
-                            .withLocale(KlockLocale.german)
-                            .format(date)
-
+                        val date = refDate + (day.number * 1000 * 60 * 60 * 24)
+                        val dateString = formatDateWithoutYear(date, Configuration.Schedule.offset)
 
                         div("wall-box") {
                             div("wall-name") {
@@ -95,8 +94,9 @@ fun Route.wall() {
                                     day.number,
                                     min,
                                     max,
-                                    day.schedules.keys.toList().sortedBy { it.id },
-                                    day.schedules
+                                    rooms,
+                                    day.schedules,
+                                    hideEmptyRooms = true
                                 )
                             }
                         }
diff --git a/src/jvmMain/kotlin/de/kif/backend/util/PushService.kt b/src/jvmMain/kotlin/de/kif/backend/util/PushService.kt
index df6ea58..fb632b9 100644
--- a/src/jvmMain/kotlin/de/kif/backend/util/PushService.kt
+++ b/src/jvmMain/kotlin/de/kif/backend/util/PushService.kt
@@ -18,7 +18,7 @@ import kotlin.concurrent.thread
 object PushService {
 
     internal var leastValidTimestamp = System.currentTimeMillis()
-    val signature = Post.generateUrl()
+    var signature = Post.generateUrl()
 
     private val messages: MutableList<Pair<Long, Message>> = mutableListOf()
 
diff --git a/src/jvmMain/resources/portal.toml b/src/jvmMain/resources/portal.toml
index 809ffa1..9222a60 100644
--- a/src/jvmMain/resources/portal.toml
+++ b/src/jvmMain/resources/portal.toml
@@ -32,3 +32,9 @@ backup_interval = 3600000
 
 [twitter]
 timeline = ""
+
+[database]
+type = "sqlite"
+url = ""
+username = ""
+password = ""