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| Field | Description |
|---|---|
| Execution Strategy | The Execution Strategy determines how this pipe should be implemented. Where this pipe is a push or pull pipe into a Merge Stream, the Default Execution Strategy is to select all stream items from the input Stream sorted by the Group By attributes, then to read items from all input pipes simultaneously, constructing candidate sets from items with matching key values. Where the Directed Execution Strategy is applied to a specific non-mandatory pipe, the other pipes with the Default Strategy operate as above, each being sorted then merged to generate a sequence of candidate sets; the Directed pipe then runs worker tasks to select the additional items by matching key value. These selects are batched up so that each worker reads items for many key values in a single select (see Worker Size), and many workers are run in parallel (see Max Workers). In general, the Directed strategy should only be used where
Changing the Execution Strategy will make the Merge faster or slower depending on the input data and the details of the input and output Streams, but will not change the business logic of the Merge (i.e. which input items are grouped into candidate sets). If the input to the pipe is a Collector, the list of key values is made available as _keyList. This will typically be used with an in clause in the Collector query. For example: select * from customer where account_num in ({_keyList}) order by account_num |
| Max Workers | The maximum number of concurrent worker tasks. If blank, this defaults to 1. |
| Worker Size | The number of key values to read for a single worker task (which runs a single select statement). If blank, this defaults to 1000. This is the maximum value that can be used when reading from an Oracle database. |
| Cache Size | Whenever data is requested down a lookup pipe, PhixFlow remembers all of the variable elements of the query i.e. the variables within any pipe filter, if the pipe is connected to a stream or file collector, or the variables within the SQL if the pipe is attached to a database collector. Any data returned by the query is then cached using the set of current values for each of these variables as the key to the cache. A warning is generated when the number of cached records exceeds 90% of the maximum, and if the number exceeds the maximum, the operation is aborted. System Configuration Default Pipe Cache Size is used. If there are likely to be a great many database lookups with different sets of variable values then the cache may end up containing a lot of data and consuming a great deal of memory. The maximum cache size can be specified to overcome this by defining the maximum number of records that the cache may contain .Each time PhixFlow retrieves data from the database, before saving the data to the cache, PhixFlow checks whether or not adding the new set of records would exceed the maximum cache size. If so then all records associated with the least used cache key (i.e. the least used set of variable values) are removed from the cache and the size checked again. If there is still not enough space then the next set of least used records are removed and so on until either there is enough space for the new set of records to be added or there are no more records in the cache. Only then can the new set of records be added to the cache. It is worth noting that once all records have been removed from the cache the new set of records can be added even if the new set on its own contains more records than the maximum cache size specified . |
| Buffer Size | The buffer size used to perform the stream calculation. If a large amount of data is being processed, then setting a large buffer size will give better performance. |
| Allow Incomplete Stream Sets | Normally, when a pipe tries to read from an input stream that contains an incomplete stream set, PhixFlow will attempt to complete the stream set before passing data down the pipe. However if the stream is static (i.e. the stream has it's 'static' flag ticked) or is effectively static (i.e. all of the pipes reading from it in this analysis run are static) then, instead of completing the stream set, an error message is produced indicating that you cannot read from this stream because it contains an incomplete stream set. If you do not want this error message to be produced when reading from static (or effectively static) streams, but would instead prefer PhixFlow to ignore the incomplete stream sets, then you must tick this box on all pipes that will read from the input stream in this analysis run. If there are multiple pipes that read from the input stream during this analysis run and even one of the pipes does not have this box ticked then you will not be allowed to read from the stream and the error message will be produced. Pipes which are not used in the current analysis run (for example where they lead to streams on branches of the model which are not run by the current task plan) have no effect on whether or not the error message is produced. |
| Data Expected | This field is available when the Pipe Type is Push or Pull. This flag allows the user to specify that the pipe is expecting to receive data. If ticked but no data is received this is treated as an error. |
| Only collect from same run | Every time the analysis engine runs all of the Streamsets that are created by all of the Streams affected by that analysis run are given the same Run ID. If this flag is ticked then the pipe will only collect Streamsets from the input Stream that have the same Run ID as the Streamset currently being created by the outpu Stream. |
| Max Stream Sets | In almost all cases this specifies the number of stream sets to be retrieved from the input stream. However, if this is a push pipe with positive offsets this value indicates the maximum number of streamsets that can be created i.e. the maximum number of cycles this pipe can initiate. |
| Historied | If ticked, the pipe will collect data from the input stream by period. So if the from and to date offsets are both 0.0, and the output stream requires stream generation for the period 17/10/07 - 18/10/07, data will be collected from the input stream for the period 17/10/07 - 18/10/07. If not ticked, all data will be collected from the input stream, regardless of period. In this case, the offsets are still used to determine whether the required data periods in the input stream exist before the stream calculation can be carried out. |
| From Date Offset | The offset applied to the start of the collection period, relative to the period in the output stream that requires populating. The units are the period of the output stream, that is, if the output stream has a daily period, then setting from date offset = -1.0 means that the start of the collection period will be 1 day earlier than the start of the period in the output stream that is being calculated. If this is a push pipe then a positive offset can be input. This will tell the stream to run again and generate another stream set. |
| To Date Offset | The offset applied to the end of the collection period, relative to the period in the output stream that requires populating. The units are the period of the output stream, that is, if the output stream has a daily period, then setting to date offset = -1.0 means that the end of the collection period will be 1 day earlier than the end of the period in the output stream that is being calculated. If this is a push pipe then a positive offset can be input. This will tell the stream to run again and generate another stream set. |
| Read Future Data | If you are running a Transactional Stream then it is possible that while your analysis run is taking place, other analysis runs which started after yours may have managed to complete before yours thereby generating additional Streamsets on the input Stream. These additional Streamsets will then have a future data relative to the date of the Streamset you are generating. By default PhixFlow will ignore input Streamsets that have a date in the future relative to the Streamset being generated.
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| Drill Down View | The drill down view is used to control what data is retrieved down the pipe and in some circumstances how that data is to be formatted. You can select from any of the views that have been configured on the source stream. The drill down view is used in three contexts. During Drill DownWhen drilling down from an alarm or stream item the drill down view is only used to determine which attributes from the source stream should be shown in the drill down display and in what order.If a view is not specified, then all attributes are shown. During Look UpsDrilldown views can also be used on lookup pipes to limit the fields that are returned by the lookup request. This is most useful in the scenario where the you want to read and cache data on a lookup pipe from a stream that has lots of attributes but where only a small number of attributes are actually required. You can simply create a new view on the source stream listing only the attributes needed, then specify it as the drilldown view on the lookup pipe. Only those attributes specified on the view will then be loaded.Without a drilldown view, the pipe will load and cache all of the attributes from the stream which may consume a significant amount of free memory if there are a large number of records. During File ExportWhen sending data to a file exporter only those fields specified on the drill down view will be exported. If no drill down view is supplied then all fields will be exported.If the file exporter is configured to export to Excel or to HTML, and no Excel template is specifed on the exporter, then the drill down view will be checked to see if an Excel template has been specified there. This template will then be used as part of the export. See the description of file exporters for further details. If an Excel template has been specified on the exporter then this will override any template specified on the drill down view. If the file exporter is configured to export to HTML and the drill down view is a chart view then the output will be a picture of the chart in PNG format. |
| Drill Down Exporter | An exporter can be selected from the set of Database Exporters configured for the input stream. This exporter can then be used from the Drill Down View. This feature is useful when PhixFlow is used to 'recommend' a set of updates. By configuring an alarm to be generated when a set of recommendations is made, the user can drill down through the alarm to see the list of recommendations and then hit the exporter icon to apply them. Any filters applied on the pipe will be applied when the data is pushed to the drill down exporter, so it is possible that not all of the data in the grid will be exported - some records may be rejected by the filter. |
| Max Records To Read | The maximum number of records that should be read down this pipe. The pipe may read more than this number of records if it is configured to carry out multiple reads simultaneously e.g. if it is connected to a File Collector which has been configured to read multiple files simultaneously or if this pipe strategy is "Directed" with multiple workers. |
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