presto-main/src/main/java/io/prestosql/sql/analyzer/ExpressionAnalyzer.java/ExpressionAnalyzer/visitDecimalLiteral
class ExpressionAnalyzer:        @Override
        protected Type visitDecimalLiteral(DecimalLiteral node, StackableAstVisitorContext<Context> context)
        {
            DecimalParseResult parseResult = Decimals.parse(node.getValue());
            return setExpressionType(node, parseResult.getType());
        }