ITrendStorageAccessReadOperator.InitializeReading (METH) ¶ METHOD InitializeReading This is the first notification, before any database access is done. InOut: Scope Name Type Comment Input sPacketName STRING The name of the packet, that has been stored in the trend storage xContinuedReading BOOL This flag indicates, whether reading is a continued reading, i.e. a reading, that continues a reading, that has to be continued, because the previous reading has to be continued, because it took too long
ITrendStorageAccessReadOperator.IsVariableToRead (METH) ¶ METHOD IsVariableToRead : BOOL Checks, whether the value of a given has to be read from TblTrendData. InOut: Scope Name Type Comment Return IsVariableToRead BOOL TRUE if the variable has to be read, otherwise FALSE Input iWhichVariable DINT A 0-based index of the variable within all variables Output idColumn CAA.IDENT Returns the column identifer of the corresponding column in TblTrendData used to retrieve the value
ITrendStorageAccessReadOperator.ProcessPacketFlags (METH) ¶ METHOD ProcessPacketFlags Notification, that the packet flags of the newest configuration has been determined and can be processed. InOut: Scope Name Type Comment Input udiPacketFlags UDINT The packet flags
ITrendStorageWriter2.AddTrendStorageWriterListener (METH) ¶ METHOD AddTrendStorageWriterListener : ETrendStorageReaderErrors Adds an ITrendStorageWriterListener instance. InOut: Scope Name Type Comment Return AddTrendStorageWriterListener ETrendStorageReaderErrors A ETrendStorageReaderErrors value indicating, whether the processing has been completed successfully or not: ETrendStorageReaderErrors.NoError: Completed successfully ETrendStorageReaderErrors.WrongParameter: If the ITrendStorageWriterListener instance is invalid ETrendStorageReaderErrors.NoMemory: If the ITrendStorageWriterListener instance cannot be stored, because no memory available Input itfTrendStorageWriterListener ITrendStorageWriterListener The ITrendStorageWriterListener instance to add
ITrendStorageWriter2.GetStatistics (METH) ¶ METHOD GetStatistics This method is used to access the statistics of the writing InOut: Scope Name Type Comment Output tAvgWriteTime TIME Returns the average time, that is needed to write to the trend storage tAvgCycleTime TIME Returns the average cycle time, when data is written to the trend storage
ITrendStorageWriter2.RemoveTrendStorageWriterListener (METH) ¶ METHOD RemoveTrendStorageWriterListener : ETrendStorageReaderErrors Removes an ITrendStorageWriterListener instance. InOut: Scope Name Type Comment Return RemoveTrendStorageWriterListener ETrendStorageReaderErrors A ETrendStorageReaderErrors value indicating, whether the processing has been completed successfully or not: ETrendStorageReaderErrors.NoError: Completed successfully ETrendStorageReaderErrors.WrongParameter: If the ITrendStorageWriterListener instance is invalid ETrendStorageReaderErrors.NoObject: If the ITrendStorageWriterListener instance cannot be removed, because was not found, i.e. has not been added with method AddTrendStorageWriterListener Input itfTrendStorageWriterListener ITrendStorageWriterListener
ITrendStorageWriter3 (ITF) ¶ INTERFACE ITrendStorageWriter3 EXTENDS ITrendStorageWriter2 Extension of interface ITrendStorageWriter2 to have the possibility to clear the complete trend history. Methods: ClearHistory AddTrendStorageWriterListener , inherited from ITrendStorageWriter2 CanProvideMinMaxTimestamps , inherited from ITrendStorageWriter CreateTrendStorageMetaDataFile , inherited from ITrendStorageWriter GetMinMaxTimestamps , inherited from ITrendStorageWriter GetStatistics , inherited from ITrendStorageWriter2 Initialize , inherited from ITrendStorageWriter InitializeGetMinMaxTimestamps , inherited from ITrendStorageWriter RemoveTrendStorageWriterListener , inherited from ITrendStorageWriter2 Structure: ClearHistory (Method)
ITrendStorageWriter3.ClearHistory (METH) ¶ METHOD ClearHistory : BOOL This method is used to clear the complete trend history InOut: Scope Name Type Return ClearHistory BOOL
ITrendStorageWriter4 (ITF) ¶ INTERFACE ITrendStorageWriter4 EXTENDS ITrendStorageWriter3 Extension of interface ITrendStorageWriter3 for improved Initialization Methods: Initialize2 AddTrendStorageWriterListener , inherited from ITrendStorageWriter2 CanProvideMinMaxTimestamps , inherited from ITrendStorageWriter ClearHistory , inherited from ITrendStorageWriter3 CreateTrendStorageMetaDataFile , inherited from ITrendStorageWriter GetMinMaxTimestamps , inherited from ITrendStorageWriter GetStatistics , inherited from ITrendStorageWriter2 Initialize , inherited from ITrendStorageWriter InitializeGetMinMaxTimestamps , inherited from ITrendStorageWriter RemoveTrendStorageWriterListener , inherited from ITrendStorageWriter2 Structure: Initialize2 (Method)
ITrendStorageSizeMonitor (ITF) ¶ INTERFACE ITrendStorageSizeMonitor EXTENDS __SYSTEM.IQueryInterface Interface to provide functions about the trend storage. Properties: ForceReorderingFailure LastReorderingTime PercDBLimit RecordSizeFactor ReorderingCount Methods: GetDatabaseFileSize Structure: ForceReorderingFailure (Property) GetDatabaseFileSize (Method) LastReorderingTime (Property) PercDBLimit (Property) RecordSizeFactor (Property) ReorderingCount (Property)
