Row selectors

Row selectors are used to indicate a set of rows in a UdbRows object. Its result is always the UdbRows object, which holds a collection of UdbRecord objects that match the parameters of the selectors.

Usage

The row selectors are passed to any .rows() function call in a Rowset or DataSource object:

$.udb( *ds* ).rows( *index*, *index* )
$.udb( *ds* ).rows( *keyword*, *indicator* )

$.udb( *ds* ).rowSet( *rowSet* ).rows( *index*, *index* )
$.udb( *ds* ).rowSet( *rowSet* ).rows( *keyword*, *indicator* )

See also the .rows() function.

Syntax

.rows( [index], [index] )
.rows( [keyword], [indicator] )

*index*    ::= Integer
*keyword*  :: 'current' | 'selected' | 'condition' | 'first' | 'last' | 'next' | 'previous' | 'id' | 'marked' | 'keystring' | 'dataset'

When using the index parameters, you can either refer to a single record, or a set range of records. When only specifying a single index, then a single record is returned. A combination of indices returns the records matching these indices, and those in-between them.

Index values are integers or arrays used to identify records in the data source:

• If you pass a single integer value, the record that corresponds to that index value is addressed.
• If you pass two integer values, the records corresponding to the first and the second index value are addressed and also all the records in between.
• If you pass an array of integer values, the records corresponding to the elements in the array are addressed.
• The index is 0-based: the first item has index 0, not 1.

When using the keyword parameter, you can select a more diverse set of records. The keyword parameter is a string value, and each value of keyword is a string that identifies a predefined option, see the table below.

If the Indicator column is empty, the indicator parameter does not apply and must be omitted; otherwise, the indicator stated is required.

Keyword	Indicator	Description
'current'		The current record (not the same as 'selected')
'dataset'	data set indicator	The records in the requested data set
'condition'	condition	The record(s) that satisfy the condition
'first'		The first record
'id'	row ID	The record with the requested row ID
'last'		The last record
'marked'		All marked records
'next'		The record following the current record
'previous'		The record preceding the current record
'selected'		All selected records (not the same as 'current')
'keystring'	Key string of a row	The record matching the specified key string

Examples

This example addresses the 5th record:

$.udb('EMP').rows(4);

and is short for:

$.udb('EMP').rowSet('current').rows(4);

This example addresses the 5th, 6th and 7th record:

$.udb('EMP').rows(4, 6);

This example addresses the records with the specified indices:

$.udb('EMP').rowSet('current').rows([0, 1, 4, 7]);

This example addresses the record following the current record:

$.udb('EMP').rows('next');

This example addresses the records in the first data set:

$.udb('EMP').rows('dataset', 1);

This example gets records that satisfy the equality condition EMPNO = 10:

$.udb('EMP').rows( { EMPNO: '10' } );

These examples get records that satisfy more complex conditions:

$.udb('EMP').rows('condition', { BIRTH_DATE: '>=01-JAN-1980' } );

$.udb('EMP').rows('condition', { BIRTH_DATE: '>=01-JAN-1980&<=01-JAN-2000' } );

To get all rows where MANAGER is NULL and SALARY is higher than 35000:

$.udb('EMP').rows('condition', { MANAGER: 'NULL', SALARY: '>35000' } );