presto-main/src/main/java/io/prestosql/sql/relational/SqlToRowExpressionTranslator.java/SqlToRowExpressionTranslator/visitBooleanLiteral
class SqlToRowExpressionTranslator:        @Override
        protected RowExpression visitBooleanLiteral(BooleanLiteral node, Void context)
        {
            return constant(node.getValue(), BOOLEAN);
        }