以下は、ISO PC 295 WG1会議（2017年5月）にて発表した資料です。修正が必要な箇所もありますが、基本方針はこれで良いと考えています。残念ながらデータ型の議論を深めることができませんでした。

Question:

Why do we need datatype besides representation?

Answer:

A common datatype makes transformation to different file format, namely delimited, xml, xbrl-gl, json more easy and simplify design effort.

DATA TYPES IN SOFTWARE PACKAGE

SAP

Data Types in the ABAP Dictionary

Predefined Elementary ABAP Types with Fixed Length

Predefined Elementary ABAP Types with Fixed Length
https://help.sap.com/saphelp_nw70/helpdata/en/fc/eb2fd9358411d1829f0000e829fbfe/frameset.htm

Predefined Elementary ABAP Types with Fixed Length
https://help.sap.com/saphelp_nw70ehp1/helpdata/en/fc/eb3138358411d1829f0000e829fbfe/content.htmz

Numeric Datatypes in SAP
https://help.sap.com/saphelp_nw70ehp1/helpdata/en/fc/eb3138358411d1829f0000e829fbfe/content.htmz
UNIT: Unit. Fields of this type are referenced by fields of type QUAN. The length of this data type is set to 2 or 3 places.

Mapping between SAP, XML and .NET

https://msdn.microsoft.com/en-us/library/cc185537(v=bts.10).aspx

ORACLE

Character String Datatypes in ORACLE

https://docs.oracle.com/cd/B28359_01/server.111/b28318/datatype.htm#CNCPT1841

NUMBER Datatype in ORACLE

The NUMBER datatype stores fixed and floating-point numbers.

Numbers of virtually any magnitude can be stored and are guaranteed portable among different systems operating Oracle Database, up to 38 digits of precision.

Numbers can be stored in a NUMBER column:

Positive numbers in the range 1 x 10-130 to 9.99…9 x 10125 with up to 38 significant digits
Negative numbers from -1 x 10-130 to 9.99…99 x 10125 with up to 38 significant digits
Zero
Positive and negative infinity (generated only by importing from an Oracle Database, Version 5)

How data is stored in ORACLE

column_name NUMBER (precision, scale)

If a precision is not specified, the column stores values as given.

If no scale is specified, the scale is zero.

Oracle guarantees portability of numbers with a precision equal to or less than 38 digits.

You can specify a scale and no precision: column_name NUMBER (*, scale)

In this case, the precision is 38, and the specified scale is maintained.

Microsoft EXCEL

Excel can store 15 decimal places accuracy.

Number in Excel

Steve Dalton (2007). “Table 2.3: Worksheet data types and limits”. Financial Applications Using Excel Add-in Development in C/C++ (2nd ed.). Wiley. pp. 13–14. ISBN 0-470-02797-5.

Auditdata collection data type

Datatype in ADCS

ADCS Legal Character

String Datatype

space(#x20), tab(#x9), carriage return(#xD), line feed(#xA), middle dot(#B7)
printable ASCII character (that is, Unicode character in the range #x21 to #x7E)