private List isPowerBiInnerJoin()

in src/query/src/main/java/org/apache/kylin/query/optrule/ExtensionOlapJoinRule.java [141:230]
73 lines of code
30 McCabe index (conditional complexity)

    private List<RexInputRef> isPowerBiInnerJoin(JoinInfo info, RexBuilder rexBuilder) {
        if (info.isEqui()) {
            return null;
        }

        // 1. top call is OR
        RexNode root = RexUtil.composeConjunction(rexBuilder, info.nonEquiConditions);
        if (!(root instanceof RexCall && root.getKind() == SqlKind.OR)) {
            return null;
        }

        // 2. operands are ANDs
        RexCall rootCall = (RexCall) root;
        if (rootCall.operands.size() != 2) {
            return null;
        }
        if (!(isOperandSqlAnd(rootCall, 0) && isOperandSqlAnd(rootCall, 1))) {
            return null;
        }

        // 3. which operand contains two IS_NULL checks
        RexCall leftCall = (RexCall) rootCall.operands.get(0);
        RexCall rightCall = (RexCall) rootCall.operands.get(1);
        RexCall twoNullCall, notNullCall;
        if (isOperandSqlIsNull(leftCall, 0) && isOperandSqlIsNull(leftCall, 1)) {
            twoNullCall = leftCall;
            notNullCall = rightCall;
        } else if (isOperandSqlIsNull(rightCall, 0) && isOperandSqlIsNull(rightCall, 1)) {
            twoNullCall = rightCall;
            notNullCall = leftCall;
        } else {
            return null;
        }

        // 4. two column refs
        RexCall isNull1 = (RexCall) twoNullCall.operands.get(0);
        RexCall isNull2 = (RexCall) twoNullCall.operands.get(1);
        if (!(isOperandInputRef(isNull1, 0) && isOperandInputRef(isNull2, 0))) {
            return null;
        }
        Set<RexInputRef> refs = Sets.newHashSet((RexInputRef) isNull1.operands.get(0),
                (RexInputRef) isNull2.operands.get(0));

        if (refs.size() != 2) {
            return null;
        }

        // 5. equal not null
        if (notNullCall.operands.size() != 3) {
            return null;
        }

        RexCall equalCall, notNull1, notNull2;
        if (isOperandSqlEq(notNullCall, 0) && isOperandSqlIsNotNull(notNullCall, 1)
                && isOperandSqlIsNotNull(notNullCall, 2)) {
            equalCall = (RexCall) notNullCall.operands.get(0);
            notNull1 = (RexCall) notNullCall.operands.get(1);
            notNull2 = (RexCall) notNullCall.operands.get(2);
        } else if (isOperandSqlEq(notNullCall, 1) && isOperandSqlIsNotNull(notNullCall, 0)
                && isOperandSqlIsNotNull(notNullCall, 2)) {
            equalCall = (RexCall) notNullCall.operands.get(1);
            notNull1 = (RexCall) notNullCall.operands.get(0);
            notNull2 = (RexCall) notNullCall.operands.get(2);
        } else if (isOperandSqlEq(notNullCall, 2) && isOperandSqlIsNotNull(notNullCall, 0)
                && isOperandSqlIsNotNull(notNullCall, 1)) {
            equalCall = (RexCall) notNullCall.operands.get(2);
            notNull1 = (RexCall) notNullCall.operands.get(0);
            notNull2 = (RexCall) notNullCall.operands.get(1);
        } else {
            return null;
        }

        if (equalCall.operands.get(0).equals(equalCall.operands.get(1))) {
            return null;
        }

        if (!(refs.contains(equalCall.operands.get(0)) && refs.contains(equalCall.operands.get(1)))) {
            return null;
        }

        if (notNull1.operands.get(0).equals(notNull2.operands.get(0))) {
            return null;
        }

        if (!(refs.contains(notNull1.operands.get(0)) && refs.contains(notNull2.operands.get(0)))) {
            return null;
        }

        return Lists.newArrayList(refs);
    }