Add fix for DB Array IO json error_check type field storage on empty save

www/lib/CoreLibs/DB/Extended/ArrayIO.inc

@@ -424,6 +424,11 @@ class ArrayIO extends \CoreLibs\DB\IO
 						$_value = 'NULL';
 					}
 					$q_data .= $_value;
+				} else {
+					// if the error check is json, we set field to null if NOT set
+					// else normal string write
+					if ($this->table_array[$column]['error_check'] == 'json' && !$this->table_array[$column]['value']) {
+						$q_data .= 'NULL';
 					} else {
 						// normal string
 						$q_data .= "'";
@@ -436,6 +441,7 @@ class ArrayIO extends \CoreLibs\DB\IO
 						$q_data .= "'";
 					}
 				}
+			}
 		} // while ...
 
 		// NOW get PK, and FK settings (FK only for update query)