Examples with IfExpression io.prestosql.sql.tree.IfExpression used on opensource projects

Example 6 with IfExpression

use of io.prestosql.sql.tree.IfExpression in project hetu-core by openlookeng.

the class AstBuilder method visitFunctionCall.

@Override
public Node visitFunctionCall(SqlBaseParser.FunctionCallContext context) {
    Optional<Expression> filter = visitIfPresent(context.filter(), Expression.class);
    Optional<Window> window = visitIfPresent(context.over(), Window.class);
    Optional<OrderBy> orderBy = Optional.empty();
    if (context.ORDER() != null) {
        orderBy = Optional.of(new OrderBy(visit(context.sortItem(), SortItem.class)));
    }
    QualifiedName name = getQualifiedName(context.qualifiedName());
    boolean distinct = isDistinct(context.setQuantifier());
    boolean ignoreNulls = context.nullTreatment() != null && context.nullTreatment().IGNORE() != null;
    if (name.toString().equalsIgnoreCase("if")) {
        check(context.expression().size() == 2 || context.expression().size() == 3, "Invalid number of arguments for 'if' function", context);
        check(!window.isPresent(), "OVER clause not valid for 'if' function", context);
        check(!distinct, "DISTINCT not valid for 'if' function", context);
        check(!filter.isPresent(), "FILTER not valid for 'if' function", context);
        Expression elseExpression = null;
        if (context.expression().size() == 3) {
            elseExpression = (Expression) visit(context.expression(2));
        }
        return new IfExpression(getLocation(context), (Expression) visit(context.expression(0)), (Expression) visit(context.expression(1)), elseExpression);
    }
    if (name.toString().equalsIgnoreCase("nullif")) {
        check(context.expression().size() == 2, "Invalid number of arguments for 'nullif' function", context);
        check(!window.isPresent(), "OVER clause not valid for 'nullif' function", context);
        check(!distinct, "DISTINCT not valid for 'nullif' function", context);
        check(!filter.isPresent(), "FILTER not valid for 'nullif' function", context);
        return new NullIfExpression(getLocation(context), (Expression) visit(context.expression(0)), (Expression) visit(context.expression(1)));
    }
    if (name.toString().equalsIgnoreCase("coalesce")) {
        check(context.expression().size() >= 2, "The 'coalesce' function must have at least two arguments", context);
        check(!window.isPresent(), "OVER clause not valid for 'coalesce' function", context);
        check(!distinct, "DISTINCT not valid for 'coalesce' function", context);
        check(!filter.isPresent(), "FILTER not valid for 'coalesce' function", context);
        return new CoalesceExpression(getLocation(context), visit(context.expression(), Expression.class));
    }
    if (name.toString().equalsIgnoreCase("try")) {
        check(context.expression().size() == 1, "The 'try' function must have exactly one argument", context);
        check(!window.isPresent(), "OVER clause not valid for 'try' function", context);
        check(!distinct, "DISTINCT not valid for 'try' function", context);
        check(!filter.isPresent(), "FILTER not valid for 'try' function", context);
        return new TryExpression(getLocation(context), (Expression) visit(getOnlyElement(context.expression())));
    }
    if (name.toString().equalsIgnoreCase("format")) {
        check(context.expression().size() >= 2, "The 'format' function must have at least two arguments", context);
        check(!window.isPresent(), "OVER clause not valid for 'format' function", context);
        check(!distinct, "DISTINCT not valid for 'format' function", context);
        check(!filter.isPresent(), "FILTER not valid for 'format' function", context);
        return new Format(getLocation(context), visit(context.expression(), Expression.class));
    }
    if (name.toString().equalsIgnoreCase("$internal$bind")) {
        check(context.expression().size() >= 1, "The '$internal$bind' function must have at least one arguments", context);
        check(!window.isPresent(), "OVER clause not valid for '$internal$bind' function", context);
        check(!distinct, "DISTINCT not valid for '$internal$bind' function", context);
        check(!filter.isPresent(), "FILTER not valid for '$internal$bind' function", context);
        int numValues = context.expression().size() - 1;
        List<Expression> arguments = context.expression().stream().map(this::visit).map(Expression.class::cast).collect(toImmutableList());
        return new BindExpression(getLocation(context), arguments.subList(0, numValues), arguments.get(numValues));
    }
    return new FunctionCall(Optional.of(getLocation(context)), getQualifiedName(context.qualifiedName()), window, filter, orderBy, distinct, ignoreNulls, visit(context.expression(), Expression.class));
}