Examples with ExpressionRewriter io.trino.sql.tree.ExpressionRewriter used on opensource projects

Example 1 with ExpressionRewriter

use of io.trino.sql.tree.ExpressionRewriter in project trino by trinodb.

the class SymbolMapper method map.

private ExpressionAndValuePointers map(ExpressionAndValuePointers expressionAndValuePointers) {
    // Map only the input symbols of ValuePointers. These are the symbols produced by the source node.
    // Other symbols present in the ExpressionAndValuePointers structure are synthetic unique symbols
    // with no outer usage or dependencies.
    ImmutableList.Builder<ValuePointer> newValuePointers = ImmutableList.builder();
    for (ValuePointer valuePointer : expressionAndValuePointers.getValuePointers()) {
        if (valuePointer instanceof ScalarValuePointer) {
            ScalarValuePointer scalarValuePointer = (ScalarValuePointer) valuePointer;
            Symbol inputSymbol = scalarValuePointer.getInputSymbol();
            if (expressionAndValuePointers.getClassifierSymbols().contains(inputSymbol) || expressionAndValuePointers.getMatchNumberSymbols().contains(inputSymbol)) {
                newValuePointers.add(scalarValuePointer);
            } else {
                newValuePointers.add(new ScalarValuePointer(scalarValuePointer.getLogicalIndexPointer(), map(inputSymbol)));
            }
        } else {
            AggregationValuePointer aggregationValuePointer = (AggregationValuePointer) valuePointer;
            List<Expression> newArguments = aggregationValuePointer.getArguments().stream().map(expression -> ExpressionTreeRewriter.rewriteWith(new ExpressionRewriter<Void>() {

                @Override
                public Expression rewriteSymbolReference(SymbolReference node, Void context, ExpressionTreeRewriter<Void> treeRewriter) {
                    if (Symbol.from(node).equals(aggregationValuePointer.getClassifierSymbol()) || Symbol.from(node).equals(aggregationValuePointer.getMatchNumberSymbol())) {
                        return node;
                    }
                    return map(node);
                }
            }, expression)).collect(toImmutableList());
            newValuePointers.add(new AggregationValuePointer(aggregationValuePointer.getFunction(), aggregationValuePointer.getSetDescriptor(), newArguments, aggregationValuePointer.getClassifierSymbol(), aggregationValuePointer.getMatchNumberSymbol()));
        }
    }
    return new ExpressionAndValuePointers(expressionAndValuePointers.getExpression(), expressionAndValuePointers.getLayout(), newValuePointers.build(), expressionAndValuePointers.getClassifierSymbols(), expressionAndValuePointers.getMatchNumberSymbols());
}