Examples with SqlAvgAggFunction org.apache.calcite.sql.fun.SqlAvgAggFunction used on opensource projects

Example 1 with SqlAvgAggFunction

use of org.apache.calcite.sql.fun.SqlAvgAggFunction in project drill by apache.

the class DrillReduceAggregatesRule method reduceAgg.

private RexNode reduceAgg(Aggregate oldAggRel, AggregateCall oldCall, List<AggregateCall> newCalls, Map<AggregateCall, RexNode> aggCallMapping, List<RexNode> inputExprs) {
    final SqlAggFunction sqlAggFunction = DrillCalciteWrapperUtility.extractSqlOperatorFromWrapper(oldCall.getAggregation());
    if (sqlAggFunction instanceof SqlSumAggFunction) {
        // case COUNT(x) when 0 then null else SUM0(x) end
        return reduceSum(oldAggRel, oldCall, newCalls, aggCallMapping);
    }
    if (sqlAggFunction instanceof SqlAvgAggFunction) {
        final SqlAvgAggFunction.Subtype subtype = ((SqlAvgAggFunction) sqlAggFunction).getSubtype();
        switch(subtype) {
            case AVG:
                // replace original AVG(x) with SUM(x) / COUNT(x)
                return reduceAvg(oldAggRel, oldCall, newCalls, aggCallMapping);
            case STDDEV_POP:
                //     / COUNT(x))
                return reduceStddev(oldAggRel, oldCall, true, true, newCalls, aggCallMapping, inputExprs);
            case STDDEV_SAMP:
                //     / CASE COUNT(x) WHEN 1 THEN NULL ELSE COUNT(x) - 1 END)
                return reduceStddev(oldAggRel, oldCall, false, true, newCalls, aggCallMapping, inputExprs);
            case VAR_POP:
                //     / COUNT(x)
                return reduceStddev(oldAggRel, oldCall, true, false, newCalls, aggCallMapping, inputExprs);
            case VAR_SAMP:
                //     / CASE COUNT(x) WHEN 1 THEN NULL ELSE COUNT(x) - 1 END
                return reduceStddev(oldAggRel, oldCall, false, false, newCalls, aggCallMapping, inputExprs);
            default:
                throw Util.unexpected(subtype);
        }
    } else {
        // anything else:  preserve original call
        RexBuilder rexBuilder = oldAggRel.getCluster().getRexBuilder();
        final int nGroups = oldAggRel.getGroupCount();
        List<RelDataType> oldArgTypes = new ArrayList<>();
        List<Integer> ordinals = oldCall.getArgList();
        assert ordinals.size() <= inputExprs.size();
        for (int ordinal : ordinals) {
            oldArgTypes.add(inputExprs.get(ordinal).getType());
        }
        return rexBuilder.addAggCall(oldCall, nGroups, oldAggRel.indicator, newCalls, aggCallMapping, oldArgTypes);
    }
}