Create Predicted Eventlog

Prerequisites

Following prerequisites need to be fullfilled to run the eventlog prediction:

• QPR ProcessAnalyzer 2024.2 or later
• Snowflake is configured
• Source model is stored to Snowflake

Prediction installation

Follow these steps to install the eventlog prediction:

1. Create a Snowflake-managed stage with name PREDICTION to the same schema that is configured for QPR ProcessAnalyzer (in the Snowflake connection string).
2. Open the created stage and upload the predict.pyz file to the stage (ask the file from your QPR representative).
3. Create the procedure procedure to the same schema.

CREATE OR REPLACE PROCEDURE QPRPA_SP_PREDICTION("CONFIGURATION" OBJECT)
RETURNS OBJECT
LANGUAGE PYTHON
STRICT
RUNTIME_VERSION = '3.8'
PACKAGES = ('nltk','numpy','pandas==1.5.3','scikit-learn','snowflake-snowpark-python','tensorflow','dill','prophet','holidays==0.18','python-kubernetes','docker-py')
HANDLER = 'main'
EXECUTE AS OWNER
AS '
import sys
def main(session, parameters_in: dict) -> dict:
	session.file.get(''@prediction/predict.pyz'', ''/tmp'')
	sys.path.append(''/tmp/predict.pyz'')
	import predict
	return predict.main(session, parameters_in)
';

1. Go to QPR ProcessAnalyzer and create the following expression script:

let predictionProcedureName = "qprpa_sp_prediction";

function RunFunctionWithParallelLogging(logTable, callbackFunc) 
{
  let state = #{};

  logTable.Truncate();

  _system.Parallel.Run([
    () => {
      try {
        state.Set("Result", callbackFunc());
      }
      finally {
        state.Set("Finished", true);
      }
    },
    () => {
      let readRows = 0;
      while (true) {
        try {
          let finished = state.TryGetValue("Finished");
          if (finished == true) {
            WriteLog(`Work finished. Log written to table ${logTable.Name} (id: ${logTable.Id})`);
            break;
          }

          let rowsDf = logTable.Synchronize().SqlDataFrame.Skip(readRows).Collect();
          readRows = readRows + rowsDf.NRows;
          rowsDf.Rows.{
            let row = _;
            WriteLog(`${row[0]} \t${row[1]}`);
          }
        }
        catch (ex) {
          if (ex.InnerExceptions?[0]?.Type == "UnauthorizedAccess") {
            WriteLog(`Log data table has disappeared. The generated log will not be complete!`);
            break;
          }
          WriteLog(`Log has not yet been created.`);
        }
      }
      Sleep(5000);
    }
  ]);
  return state.TryGetValue("Result");
}

function Train(params, logTable)
{
  function TrainCallback()
  {
    WriteLog("Starting training...");

    let connection = logTable.Project.CreateSnowflakeConnection();
    let finalParams = params.Clone();
    finalParams.Set("_typed", params["_typed"].Extend(#{
      "log_table": logTable
    }));
    let result = connection.CallStoredProcedure(predictionProcedureName, #{"configuration": finalParams});

    WriteLog("Finished training...")
    return result;
  }
  return RunFunctionWithParallelLogging(logTable, TrainCallback);
}

function Generate(params, logTable) 
{
  function GenerateCallback()
  {
    WriteLog("Starting generation...")

    let connection = logTable.Project.CreateSnowflakeConnection();

    let typedParams = params["_typed"];
    let resultEventsTable = typedParams["target_event_data_table"];
    let resultCasesTable = typedParams.TryGetValue("target_case_data_table");
    
    if (params["overwrite"]) {
      resultEventsTable.Truncate();
      resultCasesTable?.Truncate();
    }

    let finalParams = params.Clone();
    finalParams.Set("_typed", typedParams.Extend(#{
      "log_table": logTable
    }));

    let result = connection.CallStoredProcedure(predictionProcedureName, #{"configuration": finalParams});

    resultEventsTable.Synchronize();
    resultCasesTable?.Synchronize();
    
    WriteLog("Finished generation...")
    return result;
  }

  return RunFunctionWithParallelLogging(logTable, GenerateCallback);
}

function GetSampledEvents(sourceModel, sampledCaseCount, filter)
{
  if (IsNull(sampledCaseCount) || sampledCaseCount < 1)
    return sourceModel.EventsDataTable.SqlDataFrame;
  let sampleFilterRule = sampledCaseCount == null 
    ? null
    : #{
        "Type":"IncludeCases",
        "Items":[#{
          "Type": "SqlExpressionValue",
          "Configuration": #{
            "Root": `Cases.WithColumn("_Random", Rand()).OrderByColumns(["_Random"], [true]).Head(${sampledCaseCount})`
          }
        }]
      };
  let filterRules = filter?["Items"];
  if (!IsNullTop(filterRules)) {
    if (!IsNullTop(sampleFilterRule))
      filterRules = Concat(filterRules, sampleFilterRule);
  }
  else {
    if (!IsNullTop(sampleFilterRule))
      filterRules = [sampleFilterRule];
    else
      filterRules = [];
  }

  let finalFilter = #{
    "Items":filterRules
  };
  sourceModel.CacheTableSqlDataFrame(finalFilter);
}

function TrainMLModelForModel(modelName, sourceModel, targetProject, trainingConfiguration, recreatePredictionModel, trainingDataFilter, logTable, trainingCaseSampleSize)
{
  let sanitizedModelName = `${sourceModel.Id}-${modelName}`; 

  let originalCaseCount = sourceModel.EventsDataTable.SqlDataFrame.SelectDistinct([sourceModel.EventsDataTable.ColumnMappings["CaseId"]]).NRows;
  let trainEventDataSdf = GetSampledEvents(sourceModel, trainingCaseSampleSize, trainingDataFilter);
  let actualTrainingCaseSampleSize = trainEventDataSdf.SelectDistinct([trainEventDataSdf.ColumnMappings["CaseId"]]).NRows;
  WriteLog(`Starting to train a prediction model using ${ToString(100*actualTrainingCaseSampleSize/originalCaseCount, "F")}% of the original cases (${actualTrainingCaseSampleSize}/${originalCaseCount}) found in source model ${sourceModel.Name}.`)

  let trainCaseDataSdf = sourceModel.CasesDataTable?.SqlDataFrame;

  let columnMappings = trainEventDataSdf.ColumnMappings;
  if (trainCaseDataSdf != null) {
    columnMappings = columnMappings.Extend(#{"Case_CaseId": trainCaseDataSdf.ColumnMappings["CaseId"]});
  }

  trainingConfiguration = trainingConfiguration.Extend(#{ 
    "_typed": #{
      "event_data": trainEventDataSdf,  
      "project": targetProject
    },
    "model_name": sanitizedModelName,
    "column_mappings": columnMappings,
    "overwrite_model": recreatePredictionModel,
    "case_start_time_probability_multiplier": originalCaseCount / actualTrainingCaseSampleSize
  });

  if (trainCaseDataSdf != null) {
    trainingConfiguration["_typed"].Set("case_data", trainCaseDataSdf);
  }

  Train(trainingConfiguration, logTable);
}

function GenerateNewModel(modelName, sourceModel, targetProject, generationConfiguration, incompleteCasesFilter, logTable)
{
  let sanitizedModelName = `${sourceModel.Id}-${modelName}`; 
  let eventsTableName = `${modelName} - events`;
  let casesTableName = `${modelName} - cases`;
  let m = targetProject.ModelByName(modelName);
  let eventsTable = null;
  let casesTable = null;  
  if (m != null)
  {
    eventsTable = m.EventsDataTable;
    casesTable = m.CasesDataTable;
  }
  else {
    let eventsTableConfiguration = #{
      "Name": eventsTableName,
      "Type": "Snowflake"
    };
    eventsTable = targetProject.DataTableByName(eventsTableName) ?? targetProject.CreateDataTable(eventsTableConfiguration).Synchronize();
    if (sourceModel.CasesDataTable != null) {
      let casesTableConfiguration = #{
        "Name": casesTableName,
        "Type": "Snowflake"
      };
      casesTable = targetProject.DataTableByName(casesTableName) ?? targetProject.CreateDataTable(casesTableConfiguration).Synchronize();
    }
  }

  eventsTable.Truncate();
  casesTable?.Truncate();

  let generationParams, result;

  if (generationConfiguration.TryGetValue("cases_to_generate") != 0) {
    WriteLog(`Generating new cases with new events...`);

    generationParams = generationConfiguration.Extend(#{ 
      "_typed": #{
        "target_event_data_table": eventsTable,
        "project": targetProject
      },
      "model_name": sanitizedModelName,
      "overwrite": false
    });
    if (casesTable != null) {
      generationConfiguration["_typed"].Set("target_case_data_table", casesTable);
    }

    result = Generate(generationParams, logTable);

    WriteLog(`Generation results:\r\n${result}`);

    result = ParseJson(result);
    if (result["result"] != "success")
      throw result["exception"]
  }

  if (incompleteCasesFilter != null) {
    WriteLog(`Generating new events for running cases...`);
    let incompleteCasesSqlDataFrame = sourceModel.EventsDataTable.SqlDataFrame.ApplyFilter(incompleteCasesFilter, sourceModel.CasesDataTable?.SqlDataFrame);

    generationParams = generationConfiguration.Extend(#{ 
      "_typed": #{
        "event_data": incompleteCasesSqlDataFrame,  
        "target_event_data_table": eventsTable,
        "project": targetProject
      },
      "model_name": sanitizedModelName,
      "overwrite": false,
      "temperature": 0
    });
    if (casesTable != null) {
      generationConfiguration["_typed"].Set("case_data", sourceModel.CasesDataTable.SqlDataFrame);
    }

    result = Generate(generationParams, logTable);
    WriteLog(`Generation results:\r\n${result}`);

    result = ParseJson(result);
    if (result["result"] != "success")
      throw result["exception"]
  }

  if (!("Predicted".In(eventsTable.ColumnTypes.Name)))
    eventsTable
      .AddColumn("Predicted", "Boolean");

  eventsTable
    .DeleteRows(
      Column(result["column_mappings"]["events"]["EventType"]) == "__FINISH__"
    )
    .UpdateRows(
      1==1,
      "Predicted", true
    );

  if (casesTable != null) {
    if (!("Generated".In(casesTable.ColumnTypes.Name)))
      casesTable
        .AddColumn("Generated", "Boolean");

    casesTable
      .UpdateRows(
        1==1,
        "Generated", true
      );
  } 

  WriteLog(`Appending original model data...`);
  eventsTable.Import(sourceModel.EventsDataTable.SqlDataFrame, #{"Append": true});
  if (casesTable != null)
    casesTable.Import(sourceModel.CasesDataTable.SqlDataFrame, #{"Append": true});

  eventsTable
    .UpdateRows(
      Column("Predicted") == null,
      "Predicted", false
    );

  casesTable
    ?.UpdateRows(
      Column("Generated") == null,
      "Generated", false
    );

  if (m != null)
    return m;

  WriteLog(`Creating model...`);
  let eventColumnMappings = result["column_mappings"]["events"];
  let timestampMapping = eventColumnMappings["TimeStamp"];
  eventColumnMappings.Remove("TimeStamp");
  eventColumnMappings.Set("Timestamp", timestampMapping);

  let modelConfiguration = #{
    "DataSource": #{
      "Events":#{
        "DataSourceType": "datatable",
        "DataTableName": eventsTableName,
        "Columns": eventColumnMappings
      }
    }
  };

  if (casesTable != null) {
    modelConfiguration["DataSource"].Set("Cases", #{
      "DataSourceType": "datatable",
      "DataTableName": casesTableName,
      "Columns": result["column_mappings"]["cases"]
    });
  }

  targetProject.CreateModel(#{"Name": modelName, "Configuration": modelConfiguration});
}

function GeneratePredictionModel(configuration)
{
  let modelName = configuration["Name"];
  let sourceModel = configuration["SourceModel"];
  let targetProject = configuration["TargetProject"];
  let trainingConfiguration = configuration["TrainingConfiguration"];
  let generationConfiguration = configuration["GenerationConfiguration"];
  let trainingDataFilter = configuration["TrainingDataFilter"];
  let incompleteCasesFilter = configuration["IncompleteCasesFilter"];
  let recreatePredictionModel = configuration["RecreatePredictionModel"];
  let trainingCaseSampleSize = configuration["TrainingCaseSampleSize"];

  let result = null;
  let logTableName = `_MLLog:${Now}`;
  let logTable = targetProject.CreateDataTable(#{"Name": logTableName, "Type": "Snowflake"});
  try {
    WriteLog(`Training a prediction model based on model:\r\n${sourceModel.Name} (id=${sourceModel.Id})`);
    result = TrainMLModelForModel(modelName, sourceModel, targetProject, trainingConfiguration, recreatePredictionModel, trainingDataFilter, logTable, trainingCaseSampleSize);
    WriteLog(`Model training completed. Training result:\r\n${result}`);

    if (generationConfiguration != null) {
      WriteLog(`Generating a new model named ${modelName} based on trained model ${modelName}):\r\n${result}`);
      let newModel = GenerateNewModel(modelName, sourceModel, targetProject, generationConfiguration, incompleteCasesFilter, logTable);

      WriteLog(`Model ${newModel.Name} (id=${newModel.Id}) generated into project ${targetProject.Name}:\r\n${result}`);
    }
  }
  finally {
    targetProject.DataTableByName(logTableName)?.DeletePermanently();
  }
}

return #{
  "GeneratePredictionModel": GeneratePredictionModel,
  "RunFunctionWithParallelLogging": RunFunctionWithParallelLogging,
  "Train": Train,
  "Generate": Generate
};

1. Create following expression script (e.g., with name Create prediction model):

let lib = First(Project.Scripts.Where(Name == "ML library")).Run(#{});
let targetProject = Project;
lib.GeneratePredictionModel(#{
  "Name": "My prediction model",
  "SourceModel": ModelById(1),
  "TargetProject": targetProject,
  "TrainingConfiguration": #{},
  "GenerationConfiguration": #{"cases_to_generate": 1000},
  "TrainingDataFilter": null,
  "IncompleteCasesFilter": null,
  "RecreatePredictionModel": true,
  "TrainingCaseSampleSize": 1000
});

== Configure prediction ==
The prediction has the following settings (defined in the script to create the prediction model):
* Name: Name of the QPR ProcessAnalyzer model that is created to the target project. The model will contain the source model content and the predictions.
* SourceModel: Source model.
* TargetProject: Target project to create the model into.
* TrainingConfiguration: Training parameters.
* GenerationConfiguration: Event generation parameters.
* TrainingDataFilter: Optional [[Filtering_in_QPR_ProcessAnalyzer_Queries|filter]] to select specific cases to training the prediction model.
* IncompleteCasesFilter: Optional [[Filtering_in_QPR_ProcessAnalyzer_Queries|filter]] to select which for cases the prediction is made. To improve performance of the prediction, it's recommended to include only the incomplete cases for which new events might appear, and skip the completed cases for which new events are not expected anymore.
* RecreatePredictionModel: Should a prediction model be overwritten if one already exists for this source model and target model name combination. 
* TrainingCaseSampleSize: Maximum number of cases to use from the source model (random sampled).