Added _find_imbalanced() and _find_order_holes() methods as shortcuts to tag the accounting records with problems.

accounting/models.py

@@ -252,6 +252,33 @@ class Record(models.Model):
     def balance(self, value):
         self._balance = value
 
+    _is_balanced = None
+
+    @property
+    def is_balanced(self):
+        """Whether the transaction of this record is balanced. """
+        if self._is_balanced is None:
+            self._is_balanced = self.transaction.is_balanced
+        return self._is_balanced
+
+    @is_balanced.setter
+    def is_balanced(self, value):
+        self._is_balanced = value
+
+    _has_order_hole = None
+
+    @property
+    def has_order_hole(self):
+        """Whether the order of the transactions on this day is not
+        1, 2, 3, 4, 5..., and should be reordered. """
+        if self._has_order_hole is None:
+            self._has_order_hole = self.transaction.has_order_hole
+        return self._has_order_hole
+
+    @has_order_hole.setter
+    def has_order_hole(self, value):
+        self._has_order_hole = value
+
     def __str__(self):
         """Returns the string representation of this accounting
         record."""

accounting/templates/accounting/cash.html

@@ -104,15 +104,15 @@ First written: 2020/7/1
     </thead>
     <tbody>
       {% for record in records %}
-        <tr class="{% if not record.transaction.is_balanced or record.transaction.has_order_hole %} table-danger {% endif %}">
+        <tr class="{% if not record.is_balanced or record.has_order_hole %} table-danger {% endif %}">
           <td>{{ record.transaction.date|smart_date }}</td>
           <td>{{ record.subject.title|title }}</td>
-          <td>{{ record.summary|default:"" }}{% if not record.transaction.is_balanced %}
+          <td>{{ record.summary|default:"" }}{% if not record.is_balanced %}
             <span class="badge badge-danger badge-pill">
               {% trans "Unbalanced" context "Accounting|" as text %}
               {{ text|force_escape }}
             </span>
-          {% endif %}{% if record.transaction.has_order_hole %}
+          {% endif %}{% if record.has_order_hole %}
             <span class="badge badge-danger badge-pill">
               {% trans "Need Reorder" context "Accounting|" as text %}
               {{ text|force_escape }}
@@ -137,7 +137,7 @@ First written: 2020/7/1
   {# The list for small screens #}
   <ul class="list-group d-md-none">
     {% for record in records %}
-      <li class="list-group-item {% if not record.transaction.is_balanced or record.transaction.has_order_hole %} list-group-item-danger {% endif %}">
+      <li class="list-group-item {% if not record.is_balanced or record.has_order_hole %} list-group-item-danger {% endif %}">
         {% if record.sn is not None %}
           <a class="list-group-item-action" href="{{ record.transaction.get_absolute_url }}">
             <div class="date-subject-line d-flex justify-content-between align-items-center">
@@ -146,13 +146,13 @@ First written: 2020/7/1
             <div class="d-flex justify-content-between align-items-center">
               <div>
                 {{ record.summary|default:"" }}
-                {% if not record.transaction.is_balanced %}
+                {% if not record.is_balanced %}
                   <span class="badge badge-danger badge-pill">
                     {% trans "Unbalanced" context "Accounting|" as text %}
                     {{ text|force_escape }}
                   </span>
                 {% endif %}
-                {% if record.transaction.has_order_hole %}
+                {% if record.has_order_hole %}
                   <span class="badge badge-danger badge-pill">
                     {% trans "Need Reorder" context "Accounting|" as text %}
                     {{ text|force_escape }}

accounting/views/__init__.py

@@ -90,6 +90,43 @@ FROM accounting_subjects AS s
     return subjects
 
 
+def _find_imbalanced(records):
+    """"Finds the records with imbalanced transactions, and sets their
+    is_balanced attribute.
+
+    Args:
+        records (list[Record]): The accounting records.
+    """
+    with connection.cursor() as cursor:
+        cursor.execute("""SELECT transaction_sn
+  FROM accounting_records
+  GROUP BY transaction_sn
+  HAVING SUM(CASE WHEN is_credit THEN -1 ELSE 1 END * amount) != 0""")
+        imbalanced = [x[0] for x in cursor.fetchall()]
+    for record in records:
+        record.is_balanced = record.transaction.sn not in imbalanced
+
+
+def _find_order_holes(records):
+    """"Finds whether the order of the transactions on this day is not
+        1, 2, 3, 4, 5..., and should be reordered, and sets their
+        has_order_holes attributes.
+
+    Args:
+        records (list[Record]): The accounting records.
+    """
+    with connection.cursor() as cursor:
+        cursor.execute("""
+  SELECT date FROM accounting_transactions
+  GROUP BY date HAVING COUNT(*)!=MAX(ord)
+  UNION
+  SELECT date FROM accounting_transactions
+  GROUP BY date, ord HAVING COUNT(*) > 1""")
+        holes = [x[0] for x in cursor.fetchall()]
+    for record in records:
+        record.has_order_hole = record.transaction.date in holes
+
+
 @require_GET
 @digest_login_required
 def cash(request, subject_code, period_spec):
@@ -221,8 +258,11 @@ ORDER BY
         balance=balance_before))
     records.append(record_sum)
     pagination = Pagination(request, records, True)
+    records = pagination.records
+    _find_imbalanced(records)
+    _find_order_holes(records)
     return render(request, "accounting/cash.html", {
-        "records": pagination.records,
+        "records": records,
         "pagination": pagination,
         "current_subject": current_subject,
         "period": period,