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Unit 12: ADO Data Control

12.1 Recordset and Field Objects

The ADOCE control has two objects: Recordset and Field. A recordset is a virtual database table
whose fields and rows correspond to a subset of the fields and rows in an actual database table
on the Windows CE–based device. When you make additions, deletions, or changes to the
information in a recordset row, you can pass those changes to the corresponding parts of the
table. When you change data in the recordset, the recordset stores the changes in memory,
enabling you to cancel them before the underlying database is updated. ADOCE does not support
batch updates. Only one row at a time can have data that is changed but not committed to the
underlying database.
Table 12.1: Methods that the Recordset object supports

Method Description

AddNew Inserts a new row into the recordset.
CancelUpdate Cancels changes0. held in memory.
Clone Duplicates a recordset.
Close Closes a recordset.
Delete Deletes a row from the recordset.
GetRows Returns data stored in the recordset.
Move Changes the pointer to the active row in the recordset.
MoveFirst Makes the first row active.
MoveLast Makes the last row active.
MoveNext Moves the active row pointer to the next row.
MovePrevious Moves the active row pointer to the previous row.
Open Defines and opens recordsets; runs SQL commands.
Supports Determines if the recordset supports certain features.
Update Commits changes held in memory and updates the actual table.

Table 12.2: Properties that the Recordset object supports
Property Description

AbsolutePage Specifies which page to move for a new current record.
AbsolutePosition Specifies the ordinal position of a Recordset object’s current record.
ActiveConnection Sets the current database connection. Always a zero-length string (“”). For
H/PC running Pro Edition software, the name of the cdb file.
BOF Indicates whether the current record position is before the first record in
a Recordset object.
Bookmark Specifies a bookmark that uniquely identifies a record in a Recordset object.
CacheSize Specifies the number of records from a Recordset object that are cached
locally in memory.

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