Value getMergedValue(Database database, boolean distinct) {
if (distinct) {
count = 0;
groupDistinct(database);
}
Value v = null;
switch (aggregateType) {
case Aggregate.COUNT:
case Aggregate.COUNT_ALL:
v = ValueLong.get(count);
break;
case Aggregate.SUM:
case Aggregate.MIN:
case Aggregate.MAX:
case Aggregate.BOOL_OR:
case Aggregate.BOOL_AND:
v = value;
break;
case Aggregate.AVG:
case Aggregate.STDDEV_POP:
case Aggregate.STDDEV_SAMP:
case Aggregate.VAR_POP:
case Aggregate.VAR_SAMP:
return value == null ? ValueNull.INSTANCE : value;
case Aggregate.SELECTIVITY:
if (value != null) {
v = divide(value, count);
}
break;
case Aggregate.GROUP_CONCAT:
return null;
case Aggregate.HISTOGRAM:
ValueArray[] values = new ValueArray[distinctValues.size()];
int i = 0;
for (Value dv : distinctValues.keys()) {
AggregateData d = distinctValues.get(dv);
values[i] = ValueArray.get(new Value[] {dv, ValueLong.get(d.count)});
i++;
}
final CompareMode compareMode = database.getCompareMode();
Arrays.sort(
values,
new Comparator<ValueArray>() {
public int compare(ValueArray v1, ValueArray v2) {
Value a1 = v1.getList()[0];
Value a2 = v2.getList()[0];
return a1.compareTo(a2, compareMode);
}
});
v = ValueArray.get(values);
break;
default:
DbException.throwInternalError("type=" + aggregateType);
}
return v == null ? ValueNull.INSTANCE : v.convertTo(dataType);
}
private static Value divide(Value a, long by) {
if (by == 0) {
return ValueNull.INSTANCE;
}
int type = Value.getHigherOrder(a.getType(), Value.LONG);
Value b = ValueLong.get(by).convertTo(type);
a = a.convertTo(type).divide(b);
return a;
}
/**
* Get the aggregate result.
*
* @param database the database
* @param distinct if distinct is used
* @return the value
*/
Value getValue(Database database, boolean distinct) {
if (distinct) {
count = 0;
groupDistinct(database);
}
Value v = null;
switch (aggregateType) {
case Aggregate.SELECTIVITY:
{
int s = 0;
if (count == 0) {
s = 0;
} else {
m2 += distinctHashes.size();
m2 = 100 * m2 / count;
s = (int) m2;
s = s <= 0 ? 1 : s > 100 ? 100 : s;
}
v = ValueInt.get(s);
break;
}
case Aggregate.COUNT:
case Aggregate.COUNT_ALL:
v = ValueLong.get(count);
break;
case Aggregate.SUM:
case Aggregate.MIN:
case Aggregate.MAX:
case Aggregate.BOOL_OR:
case Aggregate.BOOL_AND:
v = value;
break;
case Aggregate.AVG:
if (value != null) {
v = divide(value, count);
}
break;
case Aggregate.GROUP_CONCAT:
return null;
case Aggregate.STDDEV_POP:
{
if (count < 1) {
return ValueNull.INSTANCE;
}
v = ValueDouble.get(Math.sqrt(m2 / count));
break;
}
case Aggregate.STDDEV_SAMP:
{
if (count < 2) {
return ValueNull.INSTANCE;
}
v = ValueDouble.get(Math.sqrt(m2 / (count - 1)));
break;
}
case Aggregate.VAR_POP:
{
if (count < 1) {
return ValueNull.INSTANCE;
}
v = ValueDouble.get(m2 / count);
break;
}
case Aggregate.VAR_SAMP:
{
if (count < 2) {
return ValueNull.INSTANCE;
}
v = ValueDouble.get(m2 / (count - 1));
break;
}
case Aggregate.HISTOGRAM:
ValueArray[] values = new ValueArray[distinctValues.size()];
int i = 0;
for (Value dv : distinctValues.keys()) {
AggregateData d = distinctValues.get(dv);
values[i] = ValueArray.get(new Value[] {dv, ValueLong.get(d.count)});
i++;
}
final CompareMode compareMode = database.getCompareMode();
Arrays.sort(
values,
new Comparator<ValueArray>() {
public int compare(ValueArray v1, ValueArray v2) {
Value a1 = v1.getList()[0];
Value a2 = v2.getList()[0];
return a1.compareTo(a2, compareMode);
}
});
v = ValueArray.get(values);
break;
default:
DbException.throwInternalError("type=" + aggregateType);
}
return v == null ? ValueNull.INSTANCE : v.convertTo(dataType);
}
