presto-main/src/main/java/io/prestosql/sql/relational/SqlToRowExpressionTranslator.java/SqlToRowExpressionTranslator/visitConstant
class SqlToRowExpressionTranslator:            @Override
            public RowExpression visitConstant(ConstantExpression literal, Void context)
            {
                return constant(literal.getValue(), targetType);
            }