Пример #1
0
 @Override
 void add(Database database, int dataType, boolean distinct, Value v) {
   if (v == ValueNull.INSTANCE) {
     return;
   }
   count++;
   if (distinct) {
     if (distinctValues == null) {
       distinctValues = ValueHashMap.newInstance();
     }
     distinctValues.put(v, this);
     return;
   }
   switch (aggregateType) {
     case Aggregate.SUM:
       if (value == null) {
         value = v.convertTo(dataType);
       } else {
         v = v.convertTo(value.getType());
         value = value.add(v);
       }
       break;
     case Aggregate.AVG:
       if (value == null) {
         value = v.convertTo(DataType.getAddProofType(dataType));
       } else {
         v = v.convertTo(value.getType());
         value = value.add(v);
       }
       break;
     case Aggregate.MIN:
       if (value == null || database.compare(v, value) < 0) {
         value = v;
       }
       break;
     case Aggregate.MAX:
       if (value == null || database.compare(v, value) > 0) {
         value = v;
       }
       break;
     case Aggregate.STDDEV_POP:
     case Aggregate.STDDEV_SAMP:
     case Aggregate.VAR_POP:
     case Aggregate.VAR_SAMP:
       {
         // Using Welford's method, see also
         // http://en.wikipedia.org/wiki/Algorithms_for_calculating_variance
         // http://www.johndcook.com/standard_deviation.html
         double x = v.getDouble();
         if (count == 1) {
           mean = x;
           m2 = 0;
         } else {
           double delta = x - mean;
           mean += delta / count;
           m2 += delta * (x - mean);
         }
         break;
       }
     case Aggregate.BOOL_AND:
       v = v.convertTo(Value.BOOLEAN);
       if (value == null) {
         value = v;
       } else {
         value =
             ValueBoolean.get(value.getBoolean().booleanValue() && v.getBoolean().booleanValue());
       }
       break;
     case Aggregate.BOOL_OR:
       v = v.convertTo(Value.BOOLEAN);
       if (value == null) {
         value = v;
       } else {
         value =
             ValueBoolean.get(value.getBoolean().booleanValue() || v.getBoolean().booleanValue());
       }
       break;
     case Aggregate.BIT_AND:
       if (value == null) {
         value = v.convertTo(dataType);
       } else {
         value = ValueLong.get(value.getLong() & v.getLong()).convertTo(dataType);
       }
       break;
     case Aggregate.BIT_OR:
       if (value == null) {
         value = v.convertTo(dataType);
       } else {
         value = ValueLong.get(value.getLong() | v.getLong()).convertTo(dataType);
       }
       break;
     default:
       DbException.throwInternalError("type=" + aggregateType);
   }
 }
Пример #2
0
 @Override
 void merge(Database database, int dataType, boolean distinct, Value v) {
   if (v == ValueNull.INSTANCE) {
     return;
   }
   count++;
   if (distinct) {
     if (distinctValues == null) {
       distinctValues = ValueHashMap.newInstance();
     }
     distinctValues.put(v, this);
     return;
   }
   switch (aggregateType) {
     case Aggregate.SUM:
       if (value == null) {
         value = v.convertTo(dataType);
       } else {
         v = v.convertTo(value.getType());
         value = value.add(v);
       }
       break;
     case Aggregate.MIN:
       if (value == null || database.compare(v, value) < 0) {
         value = v;
       }
       break;
     case Aggregate.MAX:
       if (value == null || database.compare(v, value) > 0) {
         value = v;
       }
       break;
     case Aggregate.BOOL_AND:
       v = v.convertTo(Value.BOOLEAN);
       if (value == null) {
         value = v;
       } else {
         value =
             ValueBoolean.get(value.getBoolean().booleanValue() && v.getBoolean().booleanValue());
       }
       break;
     case Aggregate.BOOL_OR:
       v = v.convertTo(Value.BOOLEAN);
       if (value == null) {
         value = v;
       } else {
         value =
             ValueBoolean.get(value.getBoolean().booleanValue() || v.getBoolean().booleanValue());
       }
       break;
     case Aggregate.BIT_AND:
       if (value == null) {
         value = v.convertTo(dataType);
       } else {
         value = ValueLong.get(value.getLong() & v.getLong()).convertTo(dataType);
       }
       break;
     case Aggregate.BIT_OR:
       if (value == null) {
         value = v.convertTo(dataType);
       } else {
         value = ValueLong.get(value.getLong() | v.getLong()).convertTo(dataType);
       }
       break;
       // 这5个在分布式环境下会进行重写,所以合并时是不会出现的
     case Aggregate.AVG:
     case Aggregate.STDDEV_POP:
     case Aggregate.STDDEV_SAMP:
     case Aggregate.VAR_POP:
     case Aggregate.VAR_SAMP:
     default:
       DbException.throwInternalError("type=" + aggregateType);
   }
 }