private CompareTupleFilter mergeToInClause(TupleFilter filter) {
List<? extends TupleFilter> children = filter.getChildren();
TblColRef inColumn = null;
List<String> inValues = new LinkedList<String>();
for (TupleFilter child : children) {
if (child.getOperator() == FilterOperatorEnum.EQ) {
CompareTupleFilter compFilter = (CompareTupleFilter) child;
TblColRef column = compFilter.getColumn();
if (inColumn == null) {
inColumn = column;
}
if (column == null || !column.equals(inColumn)) {
return null;
}
inValues.addAll(compFilter.getValues());
} else {
return null;
}
}
children.clear();
CompareTupleFilter inFilter = new CompareTupleFilter(FilterOperatorEnum.IN);
inFilter.addChild(new ColumnTupleFilter(inColumn));
inFilter.addChild(new ConstantTupleFilter(inValues));
return inFilter;
}
public static Pair<TupleFilter, Boolean> translate(
LookupStringTable lookup, DeriveInfo hostInfo, CompareTupleFilter compf) {
TblColRef derivedCol = compf.getColumn();
TblColRef[] hostCols = hostInfo.columns;
TblColRef[] pkCols = hostInfo.dimension.getJoin().getPrimaryKeyColumns();
if (hostInfo.type == DeriveType.PK_FK) {
assert hostCols.length == 1;
CompareTupleFilter newComp = new CompareTupleFilter(compf.getOperator());
newComp.addChild(new ColumnTupleFilter(hostCols[0]));
newComp.addChild(new ConstantTupleFilter(compf.getValues()));
return new Pair<TupleFilter, Boolean>(newComp, false);
}
assert hostInfo.type == DeriveType.LOOKUP;
assert hostCols.length == pkCols.length;
int di = derivedCol.getColumn().getZeroBasedIndex();
int[] pi = new int[pkCols.length];
int hn = hostCols.length;
for (int i = 0; i < hn; i++) {
pi[i] = pkCols[i].getColumn().getZeroBasedIndex();
}
Set<Array<String>> satisfyingHostRecords = Sets.newHashSet();
SingleColumnTuple tuple = new SingleColumnTuple(derivedCol);
for (String[] row : lookup.getAllRows()) {
tuple.value = row[di];
if (compf.evaluate(tuple)) {
collect(row, pi, satisfyingHostRecords);
}
}
TupleFilter translated;
boolean loosened;
if (satisfyingHostRecords.size() > IN_THRESHOLD) {
translated = buildRangeFilter(hostCols, satisfyingHostRecords);
loosened = true;
} else {
translated = buildInFilter(hostCols, satisfyingHostRecords);
loosened = false;
}
return new Pair<TupleFilter, Boolean>(translated, loosened);
}