The Nexacro provides X-API as a server module. Using this Nexacro API, NRE interprets the created Dataset format and displays apps on the UI screen.

This chapter explains the Dataset format created by X-API. XML files abiding by this format can be acknowledged as applicable data on the Nexacro Runtime. It is possible to develop server programs without using X-API.

Dataset XML Layout

XML Declaration
Root
	Cache
	Parameters
		Parameter (repeat)
	Dataset (repeat)
		ColumnInfo
			ConstColumn (repeat)
			Column (repeat)
		Rows
			Row (repeat)
				Col (repeat)
				OrgRow
					Col (repeat)

XML Declaration

The XML declaration is defined as follows.

<?xml version="1.0" encoding="utf-8"?>

The XML declaration should be placed at the beginning of an xml document. There should be no letter, including blanks, before the declaration.

XML Example

<?xml version="1.0" encoding="utf-8"?>
<Root xmlns="http://www.nexacroplatform.com/platform/dataset" ver="4000" >
     <Parameters>
          <Parameter id="service">stock</Parameter>
          <Parameter id="method">search</Parameter>
     </Parameters>
     <Dataset id="output">
          <ColumnInfo>
               <ConstColumn id="market" size="10" type="STRING" value="kse"/>
               <ConstColumn id="openprice" size="10" type="INT"
               value="15000"/>
               <Column id="stockCode" size="5" type="STRING"/>
               <Column id="currentprice" size="10" type="INT"/>
          </ColumnInfo>
          <Rows>
               <Row>
                    <Col id="currentCode">10001</Col>
                    <Col id="currentprice">5700</Col>
               </Row>
               <Row>
                    <Col id="currentCode">10002</Col>
                    <Col id="currentprice">14500</Col>
               </Row>
          </Rows>
     </Dataset>
</Root>

Dataset Elements

The Dataset elements are described here.

Root

Outline: The top-level element that indicates a Dataset.

Child element: Parameters, Dataset

Repeat: One

Property

<Root xmlns="http://www.nexacroplatform.com/platform/dataset">
<Root xmlns:nexacro="http://www.nexacroplatform.com/platform/dataset">
<Root xmlns=".." version="1000">

Property name	Description
xmlns	Name space, if not using a basic name space then show as xmlns:nexacro
ver	Clarifies Dataset layout version.

Parameters

Outline: An element clarifying the parameters needed for communication. The "child parameter" has the actual value, and the "parameters" element is an assemblage of (child) parameters .

Child element: Parameter

Repeat: None or one

Parameters > Parameter

Outline: Clarifies the value of a parameter

Child element: None

Repeat: None or as many as the number of parameters

Property

<Parameter id="ErrorMsg" type="STRING">SUCC</ Parameter >

Property Name	Description
id	Parameter name
type	Parameter type

Note: The Nexacro uses the required parameters described below. You need to set parameters for the interconnection with Nexacro.

<Parameter id="ErrorCode">1</Parameter>
<Parameter id="ErrorMsg">SUCC</Parameter>
<Parameter id="cachetype">Session</Parameter>

ID

ID	Description
ErrorCode	Error Code When calling the transaction function: In the case it is less than 0, which is a user defined-error, it will be processed as "fail" without reflecting UpdateStatus into InputDataset In the case it is greater than 0, which is a user defined-normal status, it will be processed as "sucess" as reflecting InputDataset into UpdateStatus When the load function is called: In the case it is less than 0, it is processed as fail defined by the user. In the case it is greater than 0, it is is processed as success as normal defined by the user. In case not designated : 0
ErrorMsg	Error Message When ErrorCode is not specified or 0, it is success. Otherwise, fail
CacheType	Defines the cache method type: Type is dynamic, static or none In case not designated : Session

Description

ErrorCode

Error Code

When calling the transaction function:
- In the case it is less than 0, which is a user defined-error, it will be processed as "fail" without reflecting UpdateStatus into InputDataset
- In the case it is greater than 0, which is a user defined-normal status, it will be processed as "sucess" as reflecting InputDataset into UpdateStatus
When the load function is called:
- In the case it is less than 0, it is processed as fail defined by the user.
- In the case it is greater than 0, it is is processed as success as normal defined by the user.
In case not designated : 0

ErrorMsg

Error Message

When ErrorCode is not specified or 0, it is success. Otherwise, fail

CacheType

Defines the cache method type:

Type is dynamic, static or none
In case not designated : Session

Type

The data type can be one of the following.

STRING: Regardless of the column size, there is no limit to the width. (However it is limited to about 2GB since the system can allot 2GB at a time)
- In the case of an empty string
  <Parameter id="ErrorMsg" type=”STRING”></Parameter>
- In the case of null
  Is divided by <Parameter id="ErrorMsg" type=”STRING”/>
INT: Whole number(-2³¹ ~ 2³¹-1)
FLOAT, DECIMAL: (±2.2X10^-308 ~±1.7X10³⁰⁸)
BIGDECIMAL: Real number(±10^-1056 ~ ±10¹⁰⁵⁶)
DATE: YYYYMMDD(-8192/01/01 ~ 8191/12/31)
DATETIME : YYYYMMDDHHmmssuuu (Possible to include msec)
TIME : 6 digits HHmmssuuu(Possible to include msec)
BLOB: Binary data

Dataset

Outline: Element that has the value of one Dataset. A Dataset has ColumnInfo which defines its structure and Rows which has the actual data as child elements.

Child element: ColumnInfo, Rows

Repeat: None or as many as the number of Dataset XML passes

Property

<Dataset id="History">

Property Name	Description
id	Dataset name

Dataset > ColumnInfo

Outline: It is used to express the Dataset schema. Child elements—ConstColumns and Columns—show the actual data. ColumnInfo is an assemblage of ConstColumns and Columns. ConstColumns show the schema of the columns with fixed values. Columns show the schema of the columns with non-fixed values.

Child element: ConstColumn, Column

Repeat: None or one

As for the child elements of ColumnInfo, ConstColumns must come before Columns.

If ConstColumns and Columns are arranged out of order, the app may not be able to process the data.

(X) When ConstColumns do not come first
<ColumnInfo>
	<Column id="stockCode" size="5" type="STRING"/>
	<Column id="currentprice" size="10" type="INT"/>
	<ConstColumn id="market" size="10" type="STRING" value="kse"/>
	<ConstColumn id="openprice" size="10" type="INT" value="15000"/>
</ColumnInfo>
...

(X) When ConstColumns and Columns are jumbled
<ColumnInfo>
	<ConstColumn id="market" size="10" type="STRING" value="kse"/>
	<Column id="currentprice" size="10" type="INT"/>
	<ConstColumn id="openprice" size="10" type="INT" value="15000"/>
	<Column id="stockCode" size="5" type="STRING"/>
</ColumnInfo>
...

Dataset > ColumnInfo > ConstColumn

Outline: Expresses the schema as Column that always has a fixed value.

Child element: None

Repeat: None or as many as the number of fixed value column

Property

<ConstColumn id="systemName"
     size="255"
     type="STRING"
     value="Production"/>

Property Name	Description
id	Column name
size	Maximum data size
type	Data type of column
value	Fixed value of column

Note: Following are the data type that can come in type.

STRING: Regardless of the column size there is no limit to the width. (However is limited to around 2GB which is the size the system can allot at once)
INT: Whole number(-2³¹ ~ 2³¹-1)
FLOAT, DECIMAL: (±2.2X10^-308 ~±1.7X10³⁰⁸)
BIGDECIMAL: Real number(±10^-1056 ~ ±10¹⁰⁵⁶)
DATE: YYYYMMDD(-8192/01/01 ~ 8191/12/31)
DATETIME : YYYYMMDDHHmmssuuu (Possible to include msec)
TIME : 6 digits HHmmssuuu(Possible to include msec)
BLOB: Second echelon data

Dataset > ColumnInfo > Column

Outline: It clarifies the value of a parameter

Child element: None

Repeat: None or as many as the number of non-fixed value columns

Property

<Column id="department"
     size="255"
     type="STRING"
     prop="text"
     sumtext="total"/>

Property Name	Description
id	Column name
size	Maximum data size
type	Data type of the column
Prop	Defines the summary type
Sumtext	Character string when prop value is text

Note: The value set in the type will be the same as the type in ColumnInfo.

The prop has the following values.

count: The number of rows of the column
sum: The sum of row values of the column
max: The maximum value of the rows in the column
min: The minimum value of the rows of the column
avg: The average of the row value of the column
Text: Sumtext property value

Dataset > Rows

Outline: It is an assemblage of the rows of a Dataset. It has a row that shows the actual data as its child element.

Child element: Row

Repeat: None or one

Dataset > Rows > Row

Outline: It expresses the data of a row in the Dataset. It has Col as its child element, which expresses value of each column. When the type is "update", it has another child element Org_Row that has the original values of a row.

Child element: Col, Org_Row

Repeat: None or as many as the number of rows of Dataset

Property

<Row type="insert">
     <Col id="currentCode">10001</Col>
     <Col id="currentprice">13400</Col>
</Row>

<Rows>
     <Row type="update">
          <Col id="currentCode">10001</Col>
          <Col id="currentprice">13400</Col>
          <OrgRow>
               <Col id="currentCode">10001</Col>
               <Col id="currentprice">13700</Col>
          </OrgRow>
     </Row>
</Rows>

<Row type="delete">
     <Col id="currentCode">10001</Col>
     <Col id="currentprice">13400</Col>
</Row>

Property Name	Description
type	insert : A row added to the original Dataset
	update: A row modified in the original Dataset. It includes Org_Row as its child element. Org_Row is the original row.
	delete: A row deleted from the original Dataset

Dataset > Rows > Row > Col

Outline: It expresses the value of each column of a Dataset

Child element: None.

Repeat: None or as many as the number of columns

Property

<Col id="department">management</Col>

Property Name	Description
Id	Column name. It Is the same as the name set in the child elements (ConstColumn, Column) of ColumnInfo

Note

In the case of an empty string:

<Col id="department"></Col> 
or
<Col id="department"/>

In the case of null, it is classified as without "tag".

Dataset > Rows > Row > OrgRow

Outline: It has the original value when the value of Dataset’s row is modified. It has Col which has the actual value as its child element.

Child element: Col

Repeat: None or one.

Note: Similar to Row which is its parent element but has no property

Dataset > Rows > Row > OrgRow > Col

Outline: It expresses the original column value before the value is modified

Child element: None

Repeat: None or as many as the number of columns

Property

<Col id="department">management</Col>

Property Name	Description
id	Column name. It is the same as the name set in the child elements (ConstColumn, Column) of ColumnInfo