dbcursorfetchex

Fetches a block of rows (called the fetch buffer) from an explicit server cursor and stores the rows in the bound program variables established using dbcursorbind.

Syntax

RETCODE dbcursorfetchex (
PDBCURSOR
hc,
INT
fetchtype,
DBINT
rownum,
DBINT
nfetchrows,
DBINT
reserved )

where

hc
Is a PDBCURSOR pointer to a server cursor returned by dbcursoropen.
fetchtype
Specifies the type of fetch to execute, changing the position of the fetch buffer within the cursor results set. The following table describes the different fetchtype values:
fetchtype Description
FETCH_FIRST Fetches the first block of rows from a dynamic or keyset cursor. The first row of the new fetch buffer is the first row in the cursor results set.
FETCH_NEXT Fetches the next block of rows from a dynamic or keyset cursor. The first row of the new fetch buffer is the row after the last row of the current fetch buffer.

If this is the first fetch using a new cursor, it behaves the same as FETCH_FIRST.

FETCH_PREV Fetches the previous block of rows from a fully dynamic or keyset cursor. The first row of the new fetch buffer is nrows (specified in dbcursoropen) before the first row of the current fetch buffer.
FETCH_RANDOM Fetches a block of rows from a keyset cursor. The first row of the new fetch buffer is the specified rownum row in the cursor results set.
FETCH_RELATIVE Fetches a block of rows from a dynamic or keyset cursor. The first row of the new fetch buffer is rownum rows before or after the first row of the current fetch buffer.
FETCH_LAST Fetches the last block of rows from a dynamic or keyset cursor. The last row of the new fetch buffer is the last row of the cursor results set.

The block of rows retrieved by a fetch is called the fetch buffer. The number of rows in the fetch buffer is determined by the nfetchrows parameter.

For a forward-only dynamic cursor (scrollopt is CUR_FORWARD in dbcursoropen), you can only use the FETCH_FIRST, FETCH_NEXT, or FETCH_RELATIVE (with a positive rownum) types.

rownum
Is the specified random or relative row number to use as the first row of the new fetch buffer. Use this parameter only with a fetchtype of FETCH_RANDOM or FETCH_RELATIVE. Specify 0 for any other fetchtype.

When fetchtype is FETCH_RANDOM:

When fetchtype is FETCH_RELATIVE:

nfetchrows
Is the number of rows in the new fetch buffer. This value must be less than or equal to the nrows parameter specified for this cursor in dbcursoropen. The poutlen and pvaraddr arrays specified in calls to dbcursorbind must have at least nfetchrows elements. If these arrays are not large enough, you must break the existing bindings and then rebind with large enough arrays (at least nfetchrows elements) before calling dbcursorfetchex.

When fetchtype is FETCH_FIRST, an nfetchrows value of 0 means that the new cursor position is set to before the beginning (first row) of the cursor results set.

When fetchtype is FETCH_LAST, an nfetchrows value of 0 means that the new cursor position is set to after the end (last row) of the cursor results set.

reserved
Reserved for future use. Use 0.

Returns

SUCCEED or FAIL.

SUCCEED is returned if every row was fetched successfully. Note that for a keyset cursor, a fetch that results in a missing row will not cause dbcursorfetchex to FAIL.

FAIL is returned if at least one of the following is true:

Remarks

After the fetch, the elements of the array of row status indicators (pstatus in dbcursoropen) are filled with row status values, one for each row in the fetch buffer. Each row status value is a series of fetch status values ORed together. The following table shows the meaning of each row status value:

Fetch status Description
FTC_SUCCEED The row was successfully fetched. The array of bound program variables and the array of data length values (specified in dbcursorbind) contain valid data for the row.
FTC_MISSING The row has been deleted or a unique index column of the row has been changed. Do not use the values in the array of bound program variables and the array of data length values (specified in dbcursorbind) for the row.

For keyset cursors, this fetch status can appear at any time. For dynamic cursors, this fetch status can appear only after the current fetch buffer is refreshed.


A row status indicator of 0 means that the row is invalid, and the values in the array of bound program variables and the array of data length values (specified in dbcursorbind) do not contain valid data. This happens when the row is before the beginning (first row) or after the end (last row) of the cursor results set.

After the fetch, the elements of the array of bound program variables and the array of data length values (previously specified in dbcursorbind):

If no fetches have been performed on a cursor, the current cursor position is before the beginning (first row) of the cursor results set.

After a fetch is complete, the new explicit server cursor position is one of the following:

When the current cursor position is before the beginning of the cursor, a FETCH_NEXT operation is identical to a FETCH_FIRST operation. When the current cursor position is after the end of the cursor, a FETCH_PREV operation is identical to a FETCH_LAST operation.

Note This function works with explicit server cursors in SQL Server 6.0. Do not use both dbcursorfetchex and dbcursorfetch with the same server cursor handle. Once one of these functions is used on a specific cursor handle, any attempt to use the other function will return fail.

Each call to dbcursorfetch leaves the DBPROCESS available for use with no pending results.

See Also

dbcursor, dbcursorbind, dbcursorcolinfo, dbcursorclose, dbcursorinfo, dbcursoropen; Bulk-Copy Functions