JSDataSet

Overview

A JSDataSet is a runtime object in Servoy designed to work with data organized in rows and columns. Unlike foundsets, it operates independently of persistent datasources, allowing developers to create and manipulate temporary datasets dynamically. This flexibility makes it ideal for handling transient data at runtime without requiring direct database connectivity.

Core Functionality

The JSDataSet supports a range of operations for managing data. Developers can add, remove, and retrieve rows and columns or set specific values within the dataset. For enhanced usability, the object provides methods to sort rows by column values or through custom comparator functions, enabling advanced data handling logic. Additionally, the dataset can be exported into formats such as HTML tables or delimited text, supporting customized data representation and integration with other Servoy features.

Temporary datasources can also be created from datasets, allowing them to be reused in forms, scripts, or even foundsets. This capability ensures the flow between runtime data generation and persistent application components. The JSDataSet is particularly effective for scenarios requiring transient data manipulation, such as on-the-fly calculations or data processing pipelines.

Properties Summarized

Type	Name	Summary
Number	rowIndex	Get or set the record index of the dataset.

Methods Summarized

Type	Name	Summary
Boolean	addColumn(name)	adds a column with the specified name to the dataset.
Boolean	addColumn(name, index)	adds a column with the specified name to the dataset.
Boolean	addColumn(name, index, type)	adds a column with the specified name to the dataset.
void	addHTMLProperty(row, col, name, value)	Add an HTML property to an HTML tag produced in getAsHTML().
void	addRow(index, array)	Add a row to the dataset.
void	addRow(array)	Add a row to the dataset.
String	createDataSource(name)	Create a datasource from the data set with specified name and using specified types.
String	createDataSource(name, types)	Create a datasource from the data set with specified name and using specified types.
String	createDataSource(name, types, pkNames)	Create a datasource from the data set with specified name and using specified types.
String	getAsHTML()	Get the dataset as an html table, do not escape values or spaces, no multi_line_markup, do not add indentation, add column names.
String	getAsHTML(escape_values)	Get the dataset as an html table, do not escape spaces, no multi_line_markup, do not add indentation, add column names.
String	getAsHTML(escape_values, escape_spaces)	Get the dataset as an html table, no multi_line_markup, do not add indentation, add column names.
String	getAsHTML(escape_values, escape_spaces, multi_line_markup)	Get the dataset as an html table, do not add indentation, add column names.
String	getAsHTML(escape_values, escape_spaces, multi_line_markup, pretty_indent)	Get the dataset as an html table, add column names.
String	getAsHTML(escape_values, escape_spaces, multi_line_markup, pretty_indent, add_column_names)	Get the dataset as an html table.
String	getAsText(column_separator, row_separator, value_delimiter, add_column_names)	Get the dataset as formatted text.
Array	getColumnAsArray(index)	Get the column data of a dataset as an Array.
String	getColumnName(index)	Get a column name based on index.
Array	getColumnNames()	Get the column names of a dataset.
Number	getColumnType(index)	Get a column type based on index.
ServoyException	getException()	Get the database exception if an error occurred.
Number	getMaxColumnIndex()	Get the number of columns in the dataset.
Number	getMaxRowIndex()	Get the number of rows in the dataset.
Array	getRowAsArray(index)	Get the row data of a dataset as an Array.
Array	getRowObject(index)	Get the row data of a dataset as an Array that can also retrieve data by column name.
Object	getValue(row, col)	Get the value specified by row and column position from the dataset.
Boolean	hadMoreData()	Return true if there is more data in the resultset then specified by maxReturnedRows at query time.
Boolean	removeColumn(index)	Remove a column by index from the dataset.
void	removeRow(row)	Remove a row from the dataset.
void	setColumnName(index, columnName)	Set a column name based on index.
void	setValue(row, col, obj)	Set the value specified by row and column position from the dataset.
void	sort(col, sort_direction)	Sort the dataset on the given column (1-based) in ascending or descending.
void	sort(comparator)	Sort the dataset using the function as comparator.

Properties Detailed

rowIndex

Get or set the record index of the dataset.

Type Number The current row index, starting from 1, or -1 if no row is selected.

Sample

//assuming the variable dataset contains a dataset
//to set the rowIndex:
dataset.rowIndex = 1 //sets the rowIndex to the first row (dataset is 1-based)
//to retrieve the rowIndex of the currently selected row
var currRow = dataset.rowIndex

Methods Detailed

addColumn(name)

adds a column with the specified name to the dataset.

Parameters

• String name column name.

Returns: Boolean true if succeeded, else false.

Sample

//assuming the variable dataset contains a dataset
var success = dataset.addColumn('columnName',1);

addColumn(name, index)

adds a column with the specified name to the dataset.

Parameters

• String name column name.

• Number index column index number between 1 and getMaxColumnIndex().

Returns: Boolean true if succeeded, else false.

Sample

//assuming the variable dataset contains a dataset
var success = dataset.addColumn('columnName',1);

addColumn(name, index, type)

adds a column with the specified name to the dataset.

Parameters

• String name column name.

• Number index column index number between 1 and getMaxColumnIndex().

• Number type the type of column, see JSColumn constants.

Returns: Boolean true if succeeded, else false.

Sample

//assuming the variable dataset contains a dataset
var success = dataset.addColumn('columnName',1);

addHTMLProperty(row, col, name, value)

Add an HTML property to an HTML tag produced in getAsHTML().

For row and col parameters use: 1 = applies to the container 0 = applies to all >0 = applies to specific cell

Parameters

• Number row row number

• Number col column number

• String name String property name

• String value String property value

Returns: void

Sample

//adds a container property (to TABLE tag)
dataset.addHTMLProperty(-1,-1,'cellspacing','3');
dataset.addHTMLProperty(-1,-1,'style','border-collapse:collapse;'); //to have a single line border

//adds a row property to all rows (to TR tag)
dataset.addHTMLProperty(0,0,'class','text');

//adds a row property to second row (to TR tag)
dataset.addHTMLProperty(2,0,'class','text');

//adds a column property to all 3rd columns (to TD tag)
dataset.addHTMLProperty(0,3,'class','redcolumn') ;

//adds a specific cell property (to TD tag)
dataset.addHTMLProperty(2,4,'color','blue');

scopes.globals.html_field = '<html>'+dataset.getAsHTML()+'</html>';

addRow(index, array)

Add a row to the dataset.

Parameters

• Number index index to add row (1-based)

• Array array row data

Returns: void

Sample

//assuming the variable dataset contains a dataset
dataset.addRow(new Array(1,2,3,4,5,6,7,7)); //adds a row with 8 columns
dataset.addRow(2, new Array(1,2,3,4,5,6,7,7)); //adds a row with 8 columns at row 2

addRow(array)

Add a row to the dataset. The row will be added as the last row.

Parameters

• Array array row data

Returns: void

Sample

//assuming the variable dataset contains a dataset
dataset.addRow(new Array(1,2,3,4,5,6,7,7)); //adds a row with 8 columns
dataset.addRow(2, new Array(1,2,3,4,5,6,7,7)); //adds a row with 8 columns at row 2

createDataSource(name)

Create a datasource from the data set with specified name and using specified types. The types are inferred from the data if possible.

A temporary datasource cannot be removed because once created there may always be forms or relations that refer to it. When the client exits, all datasources used by that client are removed automatically.

Most resources used by the datasource can be released by deleting all records: dataset.removeRow(-1) or databaseManager.getFoundSet(datasource).deleteAllRecords()

Parameters

• String name datasource name

Returns: String String uri reference to the created datasource.

Sample

ds.addColumn('my_id'); // note: use regular javascript identifiers so they can be used in scripting
ds.addColumn('my_label');
var uri = ds.createDataSource('mydata', [JSColumn.INTEGER, JSColumn.TEXT]);
var jsform = solutionModel.newForm(fname, uri, null, true, 300, 300);

var query = 'select customerid, address, city, country  from customers';
var ds2 = databaseManager.getDataSetByQuery('example_data', query, null, 999);
var uri2 = ds2.createDataSource('mydata2'); // types are inferred from query result

createDataSource(name, types)

Create a datasource from the data set with specified name and using specified types.

A temporary datasource cannot be removed because once created there may always be forms or relations that refer to it. When the client exits, all datasources used by that client are removed automatically.

Most resources used by the datasource can be released by deleting all records: dataset.removeRow(-1) or databaseManager.getFoundSet(datasource).deleteAllRecords()

A datasource can be reused if the data has the same signature (column names and types). A new createDataSource() call will clear the datasource contents from a previous call and insert the current data.

Parameters

• String name datasource name

• Object types array of types as defined in JSColumn

Returns: String String uri reference to the created datasource.

Sample

ds.addColumn('my_id'); // note: use regular javascript identifiers so they can be used in scripting
ds.addColumn('my_label');
var uri = ds.createDataSource('mydata', [JSColumn.INTEGER, JSColumn.TEXT]);
var jsform = solutionModel.newForm(fname, uri, null, true, 300, 300);

var query = 'select customerid, address, city, country  from customers';
var ds2 = databaseManager.getDataSetByQuery('example_data', query, null, 999);
var uri2 = ds2.createDataSource('mydata2'); // types are inferred from query result

createDataSource(name, types, pkNames)

Create a datasource from the data set with specified name and using specified types.

A temporary datasource cannot be removed because once created there may always be forms or relations that refer to it. When the client exits, all datasources used by that client are removed automatically.

Most resources used by the datasource can be released by deleting all records: dataset.removeRow(-1) or databaseManager.getFoundSet(datasource).deleteAllRecords()

Parameters

• String name datasource name

• Object types array of types as defined in JSColumn, when null types are inferred from the query result

• Array pkNames array of pk names, when null a hidden pk-column will be added

Returns: String String uri reference to the created datasource.

Sample

ds.addColumn('my_id'); // note: use regular javascript identifiers so they can be used in scripting
ds.addColumn('my_label');
var uri = ds.createDataSource('mydata', [JSColumn.INTEGER, JSColumn.TEXT], ['my_id']);
var jsform = solutionModel.newForm(fname, uri, null, true, 300, 300);

var query = 'select customerid, address, city, country  from customers';
var ds2 = databaseManager.getDataSetByQuery('example_data', query, null, 999);
var uri2 = ds2.createDataSource('mydata2', null, ['customerid']); // types are inferred from query result, use customerid as pk

getAsHTML()

Get the dataset as an html table, do not escape values or spaces, no multi_line_markup, do not add indentation, add column names.

Returns: String String html.

Sample

//gets a dataset based on a query
//useful to limit the number of rows
var maxReturnedRows = 10;
var query = 'select c1,c2,c3 from test_table where start_date = ?';

//to access data by name, do not use '.' or special characters in names or aliases
var args = new Array();
args[0] = order_date //or new Date();
var dataset = databaseManager.getDataSetByQuery(databaseManager.getDataSourceServerName(controller.getDataSource()),query,args,maxReturnedRows);

// gets a dataset with escape values; escape spaces (lines will not wrap); no multi-line markup; with pretty indentation; shows column names
var htmlTable = dataset.getAsHTML(true, true, false, true, true);

//assigns the dataset to a field and sets the display type to HTML_AREA
//assuming the html_field is a global text variable
scopes.globals.html_field = '<html>'+dataset.getAsHTML()+'</html>';

//Note: To display an HTML_AREA field as an HTML page, add HTML tags at the beginning '<html>' and at the end '</html>'.

getAsHTML(escape_values)

Get the dataset as an html table, do not escape spaces, no multi_line_markup, do not add indentation, add column names.

Parameters

• Boolean escape_values if true, replaces illegal HTML characters with corresponding valid escape sequences.

Returns: String String html.

Sample

//gets a dataset based on a query
//useful to limit the number of rows
var maxReturnedRows = 10;
var query = 'select c1,c2,c3 from test_table where start_date = ?';

//to access data by name, do not use '.' or special characters in names or aliases
var args = new Array();
args[0] = order_date //or new Date();
var dataset = databaseManager.getDataSetByQuery(databaseManager.getDataSourceServerName(controller.getDataSource()),query,args,maxReturnedRows);

// gets a dataset with escape values; escape spaces (lines will not wrap); no multi-line markup; with pretty indentation; shows column names
var htmlTable = dataset.getAsHTML(true, true, false, true, true);

//assigns the dataset to a field and sets the display type to HTML_AREA
//assuming the html_field is a global text variable
scopes.globals.html_field = '<html>'+dataset.getAsHTML()+'</html>';

//Note: To display an HTML_AREA field as an HTML page, add HTML tags at the beginning '<html>' and at the end '</html>'.

getAsHTML(escape_values, escape_spaces)

Get the dataset as an html table, no multi_line_markup, do not add indentation, add column names.

Parameters

• Boolean escape_values if true, replaces illegal HTML characters with corresponding valid escape sequences.

• Boolean escape_spaces if true, replaces text spaces with non-breaking space tags ( ) and tabs by four non-breaking space tags.

Returns: String String html.

Sample

//gets a dataset based on a query
//useful to limit the number of rows
var maxReturnedRows = 10;
var query = 'select c1,c2,c3 from test_table where start_date = ?';

//to access data by name, do not use '.' or special characters in names or aliases
var args = new Array();
args[0] = order_date //or new Date();
var dataset = databaseManager.getDataSetByQuery(databaseManager.getDataSourceServerName(controller.getDataSource()),query,args,maxReturnedRows);

// gets a dataset with escape values; escape spaces (lines will not wrap); no multi-line markup; with pretty indentation; shows column names
var htmlTable = dataset.getAsHTML(true, true, false, true, true);

//assigns the dataset to a field and sets the display type to HTML_AREA
//assuming the html_field is a global text variable
scopes.globals.html_field = '<html>'+dataset.getAsHTML()+'</html>';

//Note: To display an HTML_AREA field as an HTML page, add HTML tags at the beginning '<html>' and at the end '</html>'.

getAsHTML(escape_values, escape_spaces, multi_line_markup)

Get the dataset as an html table, do not add indentation, add column names.

Parameters

• Boolean escape_values if true, replaces illegal HTML characters with corresponding valid escape sequences.

• Boolean escape_spaces if true, replaces text spaces with non-breaking space tags ( ) and tabs by four non-breaking space tags.

• Boolean multi_line_markup if true, multiLineMarkup will enforce new lines that are in the text; single new lines will be replaced by , multiple new lines will be replaced by

Returns: String String html.

Sample

//gets a dataset based on a query
//useful to limit the number of rows
var maxReturnedRows = 10;
var query = 'select c1,c2,c3 from test_table where start_date = ?';

//to access data by name, do not use '.' or special characters in names or aliases
var args = new Array();
args[0] = order_date //or new Date();
var dataset = databaseManager.getDataSetByQuery(databaseManager.getDataSourceServerName(controller.getDataSource()),query,args,maxReturnedRows);

// gets a dataset with escape values; escape spaces (lines will not wrap); no multi-line markup; with pretty indentation; shows column names
var htmlTable = dataset.getAsHTML(true, true, false, true, true);

//assigns the dataset to a field and sets the display type to HTML_AREA
//assuming the html_field is a global text variable
scopes.globals.html_field = '<html>'+dataset.getAsHTML()+'</html>';

//Note: To display an HTML_AREA field as an HTML page, add HTML tags at the beginning '<html>' and at the end '</html>'.

getAsHTML(escape_values, escape_spaces, multi_line_markup, pretty_indent)

Get the dataset as an html table, add column names.

Parameters

• Boolean escape_values if true, replaces illegal HTML characters with corresponding valid escape sequences.

• Boolean escape_spaces if true, replaces text spaces with non-breaking space tags ( ) and tabs by four non-breaking space tags.

• Boolean multi_line_markup if true, multiLineMarkup will enforce new lines that are in the text; single new lines will be replaced by , multiple new lines will be replaced by

• Boolean pretty_indent if true, adds indentation for more readable HTML code.

Returns: String String html.

Sample

//gets a dataset based on a query
//useful to limit the number of rows
var maxReturnedRows = 10;
var query = 'select c1,c2,c3 from test_table where start_date = ?';

//to access data by name, do not use '.' or special characters in names or aliases
var args = new Array();
args[0] = order_date //or new Date();
var dataset = databaseManager.getDataSetByQuery(databaseManager.getDataSourceServerName(controller.getDataSource()),query,args,maxReturnedRows);

// gets a dataset with escape values; escape spaces (lines will not wrap); no multi-line markup; with pretty indentation; shows column names
var htmlTable = dataset.getAsHTML(true, true, false, true, true);

//assigns the dataset to a field and sets the display type to HTML_AREA
//assuming the html_field is a global text variable
scopes.globals.html_field = '<html>'+dataset.getAsHTML()+'</html>';

//Note: To display an HTML_AREA field as an HTML page, add HTML tags at the beginning '<html>' and at the end '</html>'.

getAsHTML(escape_values, escape_spaces, multi_line_markup, pretty_indent, add_column_names)

Get the dataset as an html table.

Parameters

• Boolean escape_values if true, replaces illegal HTML characters with corresponding valid escape sequences.

• Boolean escape_spaces if true, replaces text spaces with non-breaking space tags ( ) and tabs by four non-breaking space tags.

• Boolean multi_line_markup if true, multiLineMarkup will enforce new lines that are in the text; single new lines will be replaced by , multiple new lines will be replaced by

• Boolean pretty_indent if true, adds indentation for more readable HTML code.

• Boolean add_column_names if false, column headers will not be added to the table.

Returns: String String html.

Sample

//gets a dataset based on a query
//useful to limit the number of rows
var maxReturnedRows = 10;
var query = 'select c1,c2,c3 from test_table where start_date = ?';

//to access data by name, do not use '.' or special characters in names or aliases
var args = new Array();
args[0] = order_date //or new Date();
var dataset = databaseManager.getDataSetByQuery(databaseManager.getDataSourceServerName(controller.getDataSource()),query,args,maxReturnedRows);

// gets a dataset with escape values; escape spaces (lines will not wrap); no multi-line markup; with pretty indentation; shows column names
var htmlTable = dataset.getAsHTML(true, true, false, true, true);

//assigns the dataset to a field and sets the display type to HTML_AREA
//assuming the html_field is a global text variable
scopes.globals.html_field = '<html>'+dataset.getAsHTML()+'</html>';

//Note: To display an HTML_AREA field as an HTML page, add HTML tags at the beginning '<html>' and at the end '</html>'.

getAsText(column_separator, row_separator, value_delimiter, add_column_names)

Get the dataset as formatted text.

Parameters

• String column_separator any specified column separator; examples: tab '\t'; comma ','; semicolon ';'; space ' ' .

• String row_separator the specified row separator; examples: new line '\n'.

• String value_delimiter the specified value delimiter; null means empty string; example: double quote '"'.

• Boolean add_column_names if true column names will be added as a first row.

Returns: String String formatted text.

Sample

//assuming the variable dataset contains a dataset
//you can create csv or tab delimited results
var csv = dataset.getAsText(',','\n','"',true)
var tab = dataset.getAsText('\t','\n','"',true)

getColumnAsArray(index)

Get the column data of a dataset as an Array.

Parameters

• Number index index of column (1-based).

Returns: Array Object array of data.

Sample

//assuming the variable dataset contains a dataset
var dataArray = dataset.getColumnAsArray(1); //puts the contents from the first column of the dataset into an array
//once you have it as an array you can loop through it or feed it to a custom valuelist for example

getColumnName(index)

Get a column name based on index.

Parameters

• Number index index of column (1-based).

Returns: String String column name.

Sample

//assuming the variable dataset contains a dataset
var firstColumName = dataset.getColumnName(1) //retrieves the first columnname into the variable firstColumName
//using a loop you can get all columnames in an array:
var query = 'select * from customers';
var dataset = databaseManager.getDataSetByQuery(databaseManager.getDataSourceServerName(controller.getDataSource()), query, null, 100);
var colArray = new Array()
for (var i = 1; i <= dataset.getMaxColumnIndex(); i++)
{
	colArray[i-1] = dataset.getColumnName(i)
	//note the -1, because an array is zero based and dataset is 1 based.
}

getColumnNames()

Get the column names of a dataset.

Returns: Array String[] column names

Sample

var query = 'select * from customers';
var dataset = databaseManager.getDataSetByQuery(databaseManager.getDataSourceServerName(controller.getDataSource()), query, null, 100);
var columnNames = dataset.getColumnNames();

getColumnType(index)

Get a column type based on index.

Parameters

• Number index index of column (1-based).

Returns: Number Number the column type (JSColumn constant)

Sample

//assuming the variable dataset contains a dataset
var firstColumnType = dataset.getColumnType(1) //retrieves the first column's type into the variable firstColumnType
if (firstColumnType == JSColumn.NUMBER) { }

getException()

Get the database exception if an error occurred.

Returns: ServoyException ServoyException exception or null when not available.

Sample

//assuming the variable dataset contains a dataset
var dbException = dataset.getException();

getMaxColumnIndex()

Get the number of columns in the dataset.

Returns: Number int number of columns.

Sample

//assuming the variable dataset contains a dataset
for (var i = 1; i <= dataset.getMaxColumnIndex(); i++)
{
	colArray[i-1] = dataset.getColumnName(i)
	//have to subtract 1, because an array is zero based and a dataset is 1 based.
}

getMaxRowIndex()

Get the number of rows in the dataset.

Returns: Number int number of rows.

Sample

//assuming the variable dataset contains a dataset
var totalRows = dataset.getMaxRowIndex();

getRowAsArray(index)

Get the row data of a dataset as an Array.

Parameters

• Number index index of row (1-based).

Returns: Array Object array of data.

Sample

//assuming the variable dataset contains a dataset
var dataArray = dataset.getRowAsArray(1); //puts the contents from the first row of the dataset into an array
//once you have it as an array you can loop through it

getRowObject(index)

Get the row data of a dataset as an Array that can also retrieve data by column name.

Parameters

• Number index index of row (1-based).

Returns: Array NativeArray array of data.

Sample

//assuming the variable dataset contains a dataset
var dataArray = dataset.getRowObject(1); //puts the contents from the first row of the dataset into an array
//use dataArray[index] or dataArray.columnName

getValue(row, col)

Get the value specified by row and column position from the dataset.

Parameters

• Number row row number, 1-based

• Number col column number, 1-based

Returns: Object Object value

Sample

//assuming the variable dataset contains a dataset
var dataAtRow2Col1 = dataset.getValue(2, 1);

hadMoreData()

Return true if there is more data in the resultset then specified by maxReturnedRows at query time.

Returns: Boolean boolean more data available

Sample

var ds = databaseManager.getDataSetByQuery('example_data', 'select order_id from orders', null, 10000)
if (ds.hadMoreData())
{
	// handle large result
}

removeColumn(index)

Remove a column by index from the dataset.

Parameters

• Number index index of column to remove (1-based)

Returns: Boolean true if succeeded, else false.

Sample

//assuming the variable dataset contains a dataset
var success = dataset.removeColumn(1); // removes first column

removeRow(row)

Remove a row from the dataset.

Parameters

• Number row row index to remove, -1 for all rows

Returns: void

Sample

//assuming the variable dataset contains a dataset
dataset.removeRow(1); //removes the first row
dataset.removeRow(-1); //removes all rows

setColumnName(index, columnName)

Set a column name based on index.

Parameters

• Number index index of column (1-based).

• String columnName new column name.

Returns: void

Sample

var query = 'select customerid, customername from customers';
var dataset = databaseManager.getDataSetByQuery(databaseManager.getDataSourceServerName(controller.getDataSource()), query, null, -1);
dataset.setColumnName(2, 'name_of_customer') // change the column name for second column.

setValue(row, col, obj)

Set the value specified by row and column position from the dataset. Use row = -1, to set columnnames.

Parameters

• Number row row number, 1-based

• Number col column number, 1-based

• Object obj the value to be stored at the given row and column.

Returns: void

Sample

//assuming the variable dataset contains a dataset
dataset.setValue(2, 1,'data');

sort(col, sort_direction)

Sort the dataset on the given column (1-based) in ascending or descending.

Parameters

• Number col column number, 1-based

• Boolean sort_direction ascending (true) or descending (false)

Returns: void

Sample

// sort using column number
//assuming the variable dataset contains a dataset
dataset.sort(1, false)

sort(comparator)

Sort the dataset using the function as comparator. The comparator function is called to compare two rows, that are passed as arguments, and it will return -1/0/1 if the first row is less/equal/greater then the second row.

NOTE: starting with 7.2 release, when called on datasource(foundset) dataset, this function doesn't save the data anymore

Parameters

• Function comparator comparator function

Returns: void

Sample

//sort using comparator
dataset.sort(mySortFunction);

function mySortFunction(r1, r2)
{
	var o = 0;
	if(r1[0] < r2[0])
	{
		o = -1;
	}
	else if(r1[0] > r2[0])
	{
		o = 1;
	}
	return o;
}

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