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CDaoRecordset::FindFirst

Call this member function to find the first record that matches a specified condition.

BOOL FindFirst(
   LPCTSTR lpszFilter 
);

Parameters

  • lpszFilter
    A string expression (like the WHERE clause in a SQL statement without the word WHERE) used to locate the record.

Return Value

Nonzero if matching records are found, otherwise 0.

Remarks

The FindFirst member function begins its search from the beginning of the recordset and searches to the end of the recordset.

If you want to include all the records in your search (not just those that meet a specific condition) use one of the Move operations to move from record to record. To locate a record in a table-type recordset, call the Seek member function.

If a record matching the criteria is not located, the current record pointer is undetermined, and FindFirst returns zero. If the recordset contains more than one record that satisfies the criteria, FindFirst locates the first occurrence, FindNext locates the next occurrence, and so on.

Avviso

If you edit the current record, be sure to save the changes by calling the Update member function before you move to another record. If you move to another record without updating, your changes are lost without warning.

The Find member functions search from the location and in the direction specified in the following table:

Find operations

Begin

Search direction

FindFirst

Beginning of recordset

End of recordset

FindLast

End of recordset

Beginning of recordset

FindNext

Current record

End of recordset

FindPrevious

Current record

Beginning of recordset

Nota

When you call FindLast, the Microsoft Jet database engine fully populates your recordset before beginning the search, if this has not already been done. The first search may take longer than subsequent searches.

Using one of the Find operations is not the same as calling MoveFirst or MoveNext, however, which simply makes the first or next record current without specifying a condition. You can follow a Find operation with a Move operation.

Keep the following in mind when using the Find operations:

  • If Find returns nonzero, the current record is not defined. In this case, you must position the current record pointer back to a valid record.

  • You cannot use a Find operation with a forward-only scrolling snapshot-type recordset.

  • You should use the U.S. date format (month-day-year) when you search for fields containing dates, even if you are not using the U.S. version of the Microsoft Jet database engine; otherwise, matching records may not be found.

  • When working with ODBC databases and large dynasets, you may discover that using the Find operations is slow, especially when working with large recordsets. You can improve performance by using SQL queries with customized ORDER BY or WHERE clauses, parameter queries, or CDaoQuerydef objects that retrieve specific indexed records.

For related information, see the topic "FindFirst, FindLast, FindNext, FindPrevious Methods" in DAO Help.

Requirements

Header: afxdao.h

See Also

Reference

CDaoRecordset Class

Hierarchy Chart

CDaoRecordset::Find

CDaoRecordset::FindLast

CDaoRecordset::FindNext

CDaoRecordset::FindPrev

Other Resources

CDaoRecordset Members