private SortOrder initOrder(Session session) {
int size = groupConcatOrderList.size();
int[] index = new int[size];
int[] sortType = new int[size];
for (int i = 0; i < size; i++) {
SelectOrderBy o = groupConcatOrderList.get(i);
index[i] = i + 1;
int order = o.descending ? SortOrder.DESCENDING : SortOrder.ASCENDING;
sortType[i] = order;
}
return new SortOrder(session.getDatabase(), index, sortType, null);
}
@Override
public void updateAggregate(Session session) {
// TODO aggregates: check nested MIN(MAX(ID)) and so on
// if (on != null) {
// on.updateAggregate();
// }
HashMap<Expression, Object> group = select.getCurrentGroup();
if (group == null) {
// this is a different level (the enclosing query)
return;
}
int groupRowId = select.getCurrentGroupRowId();
if (lastGroupRowId == groupRowId) {
// already visited
return;
}
lastGroupRowId = groupRowId;
AggregateData data = (AggregateData) group.get(this);
if (data == null) {
data = AggregateData.create(type);
group.put(this, data);
}
Value v = on == null ? null : on.getValue(session);
if (type == GROUP_CONCAT) {
if (v != ValueNull.INSTANCE) {
v = v.convertTo(Value.STRING);
if (groupConcatOrderList != null) {
int size = groupConcatOrderList.size();
Value[] array = new Value[1 + size];
array[0] = v;
for (int i = 0; i < size; i++) {
SelectOrderBy o = groupConcatOrderList.get(i);
array[i + 1] = o.expression.getValue(session);
}
v = ValueArray.get(array);
}
}
}
data.add(session.getDatabase(), dataType, distinct, v);
}
@Override
public Value getValue(Session session) {
if (select.isQuickAggregateQuery()) {
switch (type) {
case COUNT:
case COUNT_ALL:
Table table = select.getTopTableFilter().getTable();
return ValueLong.get(table.getRowCount(session));
case MIN:
case MAX:
boolean first = type == MIN;
Index index = getColumnIndex();
int sortType = index.getIndexColumns()[0].sortType;
if ((sortType & SortOrder.DESCENDING) != 0) {
first = !first;
}
Cursor cursor = index.findFirstOrLast(session, first);
SearchRow row = cursor.getSearchRow();
Value v;
if (row == null) {
v = ValueNull.INSTANCE;
} else {
v = row.getValue(index.getColumns()[0].getColumnId());
}
return v;
default:
DbException.throwInternalError("type=" + type);
}
}
HashMap<Expression, Object> group = select.getCurrentGroup();
if (group == null) {
throw DbException.get(ErrorCode.INVALID_USE_OF_AGGREGATE_FUNCTION_1, getSQL());
}
AggregateData data = (AggregateData) group.get(this);
if (data == null) {
data = AggregateData.create(type);
}
Value v = data.getValue(session.getDatabase(), dataType, distinct);
if (type == GROUP_CONCAT) {
ArrayList<Value> list = ((AggregateDataGroupConcat) data).getList();
if (list == null || list.size() == 0) {
return ValueNull.INSTANCE;
}
if (groupConcatOrderList != null) {
final SortOrder sortOrder = groupConcatSort;
Collections.sort(
list,
new Comparator<Value>() {
@Override
public int compare(Value v1, Value v2) {
Value[] a1 = ((ValueArray) v1).getList();
Value[] a2 = ((ValueArray) v2).getList();
return sortOrder.compare(a1, a2);
}
});
}
StatementBuilder buff = new StatementBuilder();
String sep =
groupConcatSeparator == null ? "," : groupConcatSeparator.getValue(session).getString();
for (Value val : list) {
String s;
if (val.getType() == Value.ARRAY) {
s = ((ValueArray) val).getList()[0].getString();
} else {
s = val.getString();
}
if (s == null) {
continue;
}
if (sep != null) {
buff.appendExceptFirst(sep);
}
buff.append(s);
}
v = ValueString.get(buff.toString());
}
return v;
}