This application has encountered an unrecoverable error

<h1>This application has encountered an unrecoverable error</h1>
<p>The following has been reported to the administrator:</p>
<div class='error'>
<h2>2022-04-21 16:04:25</h2>
<p>Fatal Error: MySQL: Unknown database 'unknown' (# 1049)</p>
<p>Error in line 710 of file 'C:\xampp\htdocs\radicore\includes\dml.mysqli.class.inc'.</p>
<p>Host Info: localhost via TCP/IP<br>Server Version: 5.5.5-10.4.22-MariaDB<br>Client Version: mysqlnd 7.4.27, Character sets - client: utf8mb4, - connection: utf8mb4, - database: utf8mb4, - server: utf8mb4</p>
<p>PHP_SELF: /radicore/htm/orga_ausruestung(del1).php</p>
<p>CURRENT DIRECTORY: C:\xampp\htdocs\radicore\htm</p>
<p>SERVER_ADDR: 127.0.0.1</p>
<p>SERVER_NAME: localhost</p>
<p>HTTP_HOST: localhost</p>
<p>User Id: HVS</p>
<p>Role Id: ROLE_HT_USER</p>
<p>REMOTE_ADDR: 127.0.0.1</p>
<p>REQUEST_URI: /radicore/htm/orga_ausruestung(del1).php?csrf_id=6261646926e617.46674308&session_name=menu0</p>
</div>

<p>Page Stack:</p>
<pre>
  [0] htm_main
  [1] htm_orga
  [2] htm_orga_ausruestung(list1)
  [3] htm_orga_ausruestung(del1)
</pre>

<p>Backtrace:</p>
<pre>
0: array =
  function: string = errorHandler
  args: array =
    0: integer = 256
    1: string = MySQL: Unknown database 'unknown'
    2: string = C:\xampp\htdocs\radicore\includes\dml.mysqli.class.inc
    3: integer = 710
    4: array =
      dbname: string = unknown
      tablename: string = unknown
      where: string = orga_kontakte_ausruestung.ausruestung_id= 'TSHIRT' AND orga_kontakte_ausruestung.ausruestung_anr= '2005W-S-DHB' AND orga_kontakte_ausruestung.rdcaccount_id= '7'
1: array =
  file: string = C:\xampp\htdocs\radicore\includes\dml.mysqli.class.inc
  line: integer = 710
  function: string = trigger_error
  args: array =
    0: string = MySQL: Unknown database 'unknown'
    1: integer = 256
2: array =
  file: string = C:\xampp\htdocs\radicore\includes\std.table.class.inc
  line: integer = 11463
  function: string = getCount
  class: string = mysql
  type: string = ->
  args: array =
    0: string = unknown
    1: string = unknown
    2: string = orga_kontakte_ausruestung.ausruestung_id= 'TSHIRT' AND orga_kontakte_ausruestung.ausruestung_anr= '2005W-S-DHB' AND orga_kontakte_ausruestung.rdcaccount_id= '7'
3: array =
  file: string = C:\xampp\htdocs\radicore\includes\std.table.class.inc
  line: integer = 3790
  function: string = _dml_getCount
  class: string = Default_Table
  type: string = ->
  args: array =
    0: string = orga_kontakte_ausruestung.ausruestung_id= 'TSHIRT' AND orga_kontakte_ausruestung.ausruestung_anr= '2005W-S-DHB' AND orga_kontakte_ausruestung.rdcaccount_id= '7'
4: array =
  file: string = C:\xampp\htdocs\radicore\includes\std.table.class.inc
  line: integer = 9539
  function: string = getCount
  class: string = Default_Table
  type: string = ->
  args: array =
    0: string = orga_kontakte_ausruestung.ausruestung_id= 'TSHIRT' AND orga_kontakte_ausruestung.ausruestung_anr= '2005W-S-DHB' AND orga_kontakte_ausruestung.rdcaccount_id= '7'
5: array =
  file: string = C:\xampp\htdocs\radicore\includes\std.delete1.inc
  line: integer = 168
  function: string = validateDelete
  class: string = Default_Table
  type: string = ->
  args: array =
    0: array =
      ausruestung_id: string = TSHIRT
      ausruestung_anr: string = 2005W-S-DHB
      rdcaccount_id: string = 7
      ausruestung_marke: string = Adidas
      ausruestung_modell: string = null
      ausruestung_desc: string = T-Shirt DHB-Sichtung 2020 - 2005w
      gr_art: string = KLD-DE
      gr_art_sub: string = K
      gr_art_rdc: string = null
      ausruestung_farbe: string = grau
      ausruestung_farbnummer: string = null
      ausruestung_preis_netto: string = 0.00
      ausruestung_preis_rabatt: string = 0.000
      ausruestung_preis_rabatt_berechnen: string = 0
      ausruestung_preis_mwst: string = 0.00
      ausruestung_preis_mwst_berechnen: string = 1
      ausruestung_preis_brutto: string = 0.00
      ausruestung_preis_eigenanteil: string = 0.00
      ausruestung_pfad_bild: string = null
      ausruestung_pfad_video: string = null
      ausruestung_barcode: string = null
      ausruestungs_groesse_art_desc: string = null
6: array =
  file: string = C:\xampp\htdocs\radicore\htm\orga_ausruestung(del1).php
  line: integer = 34
  args: array =
    0: string = C:\xampp\htdocs\radicore\includes\std.delete1.inc
  function: string = require

</pre>