Programmatic DQ

Don't like leaving your notebook? Want to build data quality into your in-house data quality pipeline? Collibra DQ can do both!

Real World Examples


Let's assume we were provided a file named "atm_cust_file" and want to load it into a database table as well as scan it for all possible errors. We want to provide a couple levels of protection. 1) A business rule checking if a customer joined before before the company was founded. 2) Check if the file 100% matches to the DataFrame or db table we've created. 3) Check for all possible outliers or anomalies in the dataset. Each one of these 3 issues had a different impact to the business and causes a different flow to trigger in our pipeline.

Add Rule

Let's create a simple rule and assign points to the overall scoring system for later delegation.

    val rule = new Rule
    rule.setRuleValue("customer_since_date < '1956-11-01'")
    OwlUtils.addRule (rule)

Now let's chain together the remaining two items that were part of our original requirement. Note that DQ has six additional ML DQ features that we did not turn on in this case.

val df_source = (
.format ("csv").option("header", true).option("delimiter", ",")
val dataset = "atm_customer"
var date = "2018-01-16"

val optSource = new SourceOpt
optSource.on = true
optSource.dataset = dataset
optSource.validateValues = true
optSource.key = Array("name")
//Dataframe for the table created from the file

val connProps = Map (
"driver"    -> "org.postgresql.Driver",
"user"        -> "postgres",
"password"    -> "xxx",
"url"        -> "jdbc:postgresql://xxx:xxx/postgres",
"dbtable"    -> "public.atmCustomer" )
val df_target ="jdbc").options(connProps).load
val cdq = OwlUtils.OwlContext(df_source, df_target, opt)
.register (opt)
// first register with catalog if not registered
cdq.register (props)
// Check if dataframe matches the source file 'atm_cust_file'
val breakCountDF = cdq.getSourceBreaksCount()
if (breakCountDf.count() > 1) {
  // create service now ticket and exit with fail based on not matching to original file
val ruleBreaks = cdq1.getRuleBreakRows()
if (ruleBreaks.count() > 1) {
  if (ruleBreaks.where($"score" > 5).count > 1) {
    //create service now ticket and exit with fail based on rules
val outliers = cdq.getOutliers()
if (outliers.where($"confidence" < 10).count > 3) {
  // CDQ email Alert to business group for attention
  // where 3 outliers have a confidence below 10

Ingesting Intraday Files

Here we illustrate an example of how to work with files when using DQ programmatically. This can be implemented in both a Notebook setting and in your own codebase.

    //                  USE CASE - Ingesting Intraday Files                  //

    // Part of your pipeline includes the ingestion of files that have the date
    // and hour encoded in the file name. How do you process those files using Collibra DQ?
    // Format: <name>_<year>_<month>_<day>.csv
    // Build up a data structure containg the files you want to process (here we
    // just use a simple list, but you may want to be pulling from a pubsub
    // queue, AWS bucket, etc...). Here we just use a simple file list of 6
    // hours of trade position data.
    val position_files = List( new File(getClass.getResource("/position_file_2019_11_03_08.csv").getPath),
      new File(getClass.getResource("/position_file_2019_11_03_09.csv").getPath),
      new File(getClass.getResource("/position_file_2019_11_03_08.csv").getPath),
      new File(getClass.getResource("/position_file_2019_11_03_09.csv").getPath),
      new File(getClass.getResource("/position_file_2019_11_03_10.csv").getPath),
      new File(getClass.getResource("/position_file_2019_11_03_11.csv").getPath),
      new File(getClass.getResource("/position_file_2019_11_03_12.csv").getPath),
      new File(getClass.getResource("/position_file_2019_11_03_13.csv").getPath),
      new File(getClass.getResource("/position_file_2019_11_03_14.csv").getPath))

    // Create your spark session.
    val spark = SparkSession.builder

    // Configure Collibra DQ
    val opt = new OwlOptions
    opt.dataset = "positions"
    opt.load.delimiter = ","
    opt.spark.master = "local[1]"
    opt.dupe.on = true
    opt.dupe.include = Array("ticker", "cid")
    opt.outlier.on = true
    opt.outlier.key = Array("cid")
    opt.outlier.timeBin = TimeBin.HOUR
    // Customize this to only process a subset of the data.
    opt.load.fileQuery = "select * from dataset"

    position_files.foreach { file: File =>
      // Tell Collibra DQ where to find the file.
      opt.load.filePath = file.getPath

      // Parse the filename to construct the run date (-rd) that will be passed
      // to Collibra DQ.
      val name = file.getName.split('.').head
      val parts = name.split("_")
      val date = parts.slice(2, 5).mkString("-")
      val hour = parts.takeRight(1).head

      // Must be in format 'yyyy-MM-dd' or 'yyyy-MM-dd HH:mm'.
      val rd = s"${date} ${hour}"

      // Tell Collibra DQ to process data
      opt.runId = rd

      // Create a DataFrame from the file.
      val df = OwlUtils.load(opt.load.filePath, opt.load.delimiter, spark)

      // Instantiate an OwlContext with the dataframe and our custom configuration.
      val cdq = OwlUtils.OwlContext(df, spark, opt)

      // Make sure Collibra DQ has catalogued the dataset.

      // Let Collibra DQ do the rest!


All Pipeline Activities in One Line

For brevity and convenience, DQ allows a DF to be loaded in the constructor and in one line run all nine dimensions of data quality "cdq.owlcheck()". To adjust the DQ dimensions you simply set the properties in the props object.

val cdq = Util.OwlContext(df, atmCustFileDF, opts)

Example of some common property settings

val props = new Props()
props.filePath = s"${filePath}/atm_customer_${rd.replace("-","_")}.csv"
props.runId = rd
props.dateCol = "OWL_RUN_ID"
props.dataset = "ATM_CUSTOMER3"
props.del = ","
props.datasetSafety = false
props.calculateBoundaries = true
props.fileLookBack = true
props.timeBin = "DAY"

// outlier, missing records
props.dl = true
props.dlKey = "customer_id"
props.dlLb = 4

// pattern mining
props.freqPatternMiningByKey = true
props.fpgKey = "customer_id"
props.fpgLookback = 4
props.fpgDateCol = "OWL_RUN_ID"
props.fpgCols = "card_number,first_name,last_name,checking_savings"
props.fpgLowFreq = true

// validate Src
props.validateSrc = true
props.valSrcKey = "customer_id"

// fuzzy match
props.isDupe = true
props.dupeCutOff = 88
props.depth = 3
props.dupeExcludeCols = "customer_id,card_number,customer_since_date,OWL_RUN_ID"