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Поддержка курсоров


Поддержка курсоров



Each function listed below returns information about a cursor, or performs a task that performs a cursor-related task such as positioning of a cursor, linking of cursors, creating and closing cursors, counting of records associated with a cursor, filtering, setting and comparing bookmarks, and refreshing all buffers associated with a cursor.



DbiActivateFilter:
Activates a filter.

DbiAddFilter:


Adds a filter to a table, but does not activate the filter (the record set is not yet altered).

DbiApplyDelayedUpdates:
When cached updates cursor layer is active, writes all modifications made to cached data to the
underlying database.

DbiBeginDelayedUpdates:
Creates a cached updates cursor layer so that users can make extended changes to temporarily
cached table data without writing to the actual table, thereby minimizing resource locking.

DbiBeginLinkMode:
Converts a cursor to a link cursor. Given an open cursor, prepares for linked access. Returns a
new cursor.

DbiCloneCursor:
Creates a new cursor (clone cursor) which has the same result set as the given cursor
(source cursor).

DbiCloseCursor:
Closes a previously opened cursor.

DbiCompareBookMarks:
Compares the relative positions of two bookmarks in the result set associated with the cursor.

DbiDeactivateFilter:
Temporarily stops the specified filter from affecting the record set by turning the filter off.

DbiDropFilter:
Deactivates and removes a filter from memory, and frees all resources.

DbiEndDelayedUpdates:
Closes a cached updates cursor layer ending the cached updates mode.

DbiEndLinkMode:
Ends linked cursor mode, and returns the original cursor.

DbiExtractKey:
Retrieves the key value for the current record of the given cursor or from the supplied record buffer.

DbiForceRecordReread:
Rereads a single record from the server on demand, refreshing one row only, rather than clearing
the cache.

DbiForceReread:
Refreshes all buffers associated with the cursor, if necessary.

DbiFormFullName:
Returns the fully qualified table name.

DbiGetBookMark:
Saves the current position of a cursor to the client-supplied buffer called a bookmark.

DbiGetCursorForTable:
Finds the cursor for the given table.

DbiGetCursorProps:
Returns the properties of the cursor.

DbiGetExactRecordCount:
Retrieves the current exact number of records associated with the cursor. NEW FUNCTION BDE 4.0

DbiGetFieldDescs:
Retrieves a list of descriptors for all the fields in the table associated with the cursor.

DbiGetLinkStatus:
Returns the link status of the cursor.

DbiGetNextRecord:
Retrieves the next record in the table associated with the cursor.

DbiGetPriorRecord:
Retrieves the previous record in the table associated with the given cursor.

DbiGetProp:
Returns a property of an object.

DbiGetRecord:
Retrieves the current record, if any, in the table associated with the cursor.

DbiGetRecordCount:
Retrieves the current number of records associated with the cursor.

DbiGetRecordForKey:
Finds and retrieves a record matching a key and positions the cursor on that record.

DbiGetRelativeRecord:
Positions the cursor on a record in the table relative to the current position of the cursor.

DbiGetSeqNo:
Retrieves the sequence number of the current record in the table associated with the cursor.

DbiLinkDetail:
Establishes a link between two tables such that the detail table has its record set limited to the
set of records matching the linking key values of the master table cursor.

DbiLinkDetailToExp:
Links the detail cursor to the master cursor using an expression.

DbiMakePermanent:
Changes a temporary table created by DbiCreateTempTable into a permanent table.

DbiOpenTable:
Opens the given table for access and associates a cursor handle with the opened table.

DbiResetRange:
Removes the specified table's limited range previously established by the function DbiSetRange.

DbiSaveChanges:
Forces all updated records associated with the cursor to disk.

DbiSetFieldMap:
Sets a field map of the table associated with the given cursor.

DbiSetProp:
Sets the specified property of an object to a given value.

DbiSetRange:
Sets a range on the result set associated with the cursor.

DbiSetToBegin:
Positions the cursor to BOF (just before the first record).

DbiSetToBookMark:
Positions the cursor to the location saved in the specified bookmark.

DbiSetToCursor:
Sets the position of one cursor (the destination cursor) to that of another (the source cursor).

DbiSetToEnd:
Positions the cursor to EOF (just after the last record).

DbiSetToKey:
Positions an index-based cursor on a key value.

DbiSetToRecordNo:
Positions the cursor of a dBASE table to the given physical record number.

DbiSetToSeqNo:
Positions the cursor to the specified sequence number of a Paradox table.

DbiUnlinkDetail:
Removes a link between two cursors.


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