NexusDB

 
Declaration

TnxAbstractCursor = class(TnxAbstractTimeoutObject)

 
Description

The abstract declaration of a Server cursor. All actual cursor implementations must be descendent from this class. This is the server side version of TnxCursor.

 
Methods

AfterConstruction

see TObject.AfterConstruction

AutoIncGet

AutoIncSet

This function sets the next AutoInc value for the current table.

BeforeDestruction

see TObject.BeforeDestruction.

BlobCreate

This function creates a new blob and returns the new blob reference number in aBlobNr. This number is unique for any blob and is needed to access the blob.

BlobCreateFile

This creates a new FileBlob and returns the new blob reference number in aBlobNr. This number is unique for any blob and is needed to access the blob.

BlobDelete

This function deletes the blob with the given aBlobNr.

BlobFree

???

BlobGetLength

This function returns the length of the blob in aLengt as bytes.

BlobModified

The text for this method has been generated automatically. This means that it is not documented.

BlobRead

This function reads data from a blob.

BlobTruncate

This function truncates the given blob at aBlobLength bytes.

BlobWrite

This function writes data to a blob.

BookmarkAsVariant

The text for this method has been generated automatically. This means that it is not documented.

CompareBookmarks

This function compares two bookmarks.

CompareKeys

The text for this method has been generated automatically. This means that it is not documented.

CopyRecords

This function copies *all* visible (in regards of ranges and filters) records to the cursor given in aDestCursor. aMaxTransSize specifies the maximum number of dirty transaction bytes before the transaction is committed.

CopyRecordsEx

This function copies *all* visible (in regards of ranges and filters) records to the cursor given in aDestCursor. aMaxTransSize specifies the maximum number of dirty transaction bytes before the transaction is committed. aCheckReqFields determines wether a check is done for required fields having a value.

Create

Constructor

DeleteRecords

This function deletes *all* visible (in regards of ranges and filters) records.

Destroy

destructor.

Duplicate

This function clones the current cursor and returns a new instance in aNewCursor. The new cursor can be opened with a different mode by specifying the aOpenMode accordingly.

FilterActivate

This function sets the given Filter to active.

FilterAddCallback

???

FilterAddCustom

???

FilterAddExpression

FilterAddExpression creates a new Filter instance for the given aExpression and returns its in aFilterID.

FilterDeactivate

This function sets the given Filter to inactive.

FilterRemove

This function removes the given Filter from the internal list.

FilterSetTimeout

This function sets the timeout for the filter evaluation in msec.

GetBookmark

GetIndexID

This function returns the id of the current index.

GetRecordCount

GetRecordCount returns the number of currently "visible" records. It obeys set ranges and filters.

GetRecordCountAsync

This function is an asynchronous version of GetRecordCount.

GetRecordCountEx

GetRecordCountEx returns the number of records or keys based on the value of aOption.

GetRecordCountExAsync

This function is an asynchronous version of GetRecordCountEx.

LookupByID

This is the class function that returns the object with a certain ID.

RangeReset

This function cancels the active range.

RangeSet

???

RecNoGet

The text for this method has been generated automatically. This means that it is not documented.

RecNoSet

The text for this method has been generated automatically. This means that it is not documented.

RecNoSupported

recno support

RecordDelete

RecordDelete deletes the current record and returns a pointer to the then current record buffer. It needs to be able to acquire the given lock type for this function to be successful.

RecordGet

RecordGet returns a pointer to the current record buffer. It needs to be able to acquire the given lock type for this function to be successful.

RecordGetBatch

This function returns a batch of record data in a Stream. aCutoffSize - the maximum length to return in bytes. aOptions - the (blob/bookmark) options to use for filling the stream aStream - the stream that receives the data aMaxRecords - the maximum number of records to return.

RecordGetForKey

???

RecordGetNext

RecordGet moves to the next valid (in regards of ranges and filters) record returns a pointer to the then current record buffer. It needs to be able to acquire the given lock type for this function to be successful.

RecordGetPrior

RecordGet moves to the prior valid (in regards of ranges and filters) record returns a pointer to the then current record buffer. It needs to be able to acquire the given lock type for this function to be successful.

RecordInsert

RecordInsert creates a new record and returns a pointer to the then current record buffer. It needs to be able to acquire the given lock type for this function to be successful.

RecordInsertBatch

This function adds the data in a aStream as new records. Please note that the size of aStream must be a multiple of the record size.

RecordIsLocked

RecordIsLocked returns the current record lock state for a certain lock type.

RecordLockRelease

This function releases the last lock or alternatively all locks in the record.

RecordModify

RecordInsert sets the record buffer to the give data. The record must have a proper lock acquired for this function to succeed. If aReleaseLock is true all locks on the current record are released.

RequestNestedTransactions

This function can be called from an extender to request that the cursor uses nested transactions for all operations. By default this is not supported.

SetToBegin

SetToBookmark

This function will position the cursor on the given bookmark

SetToCursor

This function synchronizes the position with the given aCursor. Please note that the two cursor have to point to the same dataset.

SetToEnd

This function sets the cursor position to the end of the dataset. This is NOT the last record but after it!

SetToFilter

This function sets the cursor position before the first record that meets the filter criteria in aFilter.

SetToKey

???

SwitchToIndex

SwitchToIndex activates the given index. It aPosOnRec it repositions the cursor to the record active before changing the index, otherwise it jumps to the first record.

TableIsLocked

TableIsLocked returns the current table lock state for a certain lock type.

TableLockAcquire

This function will try to acquire a table lock with the given aLockType.

TableLockRelease

This function will release and acquired lock with the given aLockType or alternatively (if aAllLocks is true) all locks on the table.

TableStreamDelete

This function deletes the table stream with the given aName.

TableStreamGetList

This function returns the names of all streams stored with the table.

TableStreamRead

This function reads the WHOLE stream with the given name into aStream.

TableStreamWrite

This function rewrites the WHOLE stream with the given name.

 
Properties

Database

This property returns the database the cursor is linked to.

Dictionary

This property returns the data dictionary for this cursor.

 
File

 
nxsdServerEngine