Function: Basic SQL++ SELECT Statement

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      Goal: Iterate through a basic N1QL SELECT where Eventing interacts with the Data service via an inline {sqlpp} statement.

      • This function basicN1qlSelectStmt demonstrates how to use an inline N1QL SELECT statement with a passed parameter.

      • Requires the "travel-sample" sample dataset to be loaded.

      • Requires Eventing Storage (or metadata collection) and a "source" collection of travel-sample.inventory.airline.

      • Assuming you deployed "From now" mutate any document in "travel-sample" to generate a log line.

      • For more detail refer to SQL++ Statements.

      • Configure the Function with a Feed Boundary "From now" (Note you will log 187 lines if you use "Everything").

      • [Optional] if Feed Boundary is "Everything" you can use SQL++ to add an index for performance:

        • CREATE INDEX adv_airline_type ON default:`travel-sample`.inventory.route(airline) WHERE (type = 'route')

      • basicN1qlSelectStmt

      • Input Data/Mutation (via the following SQL++ statement)

      • Output Data/Logged

      // To run configure the settings for this Function, basicN1qlSelectStmt, as follows:
      //
      // Version 7.1+
      //   "Function Scope"
      //     *.* (or try travel-sample.inventory if non-privileged)
      // Version 7.0+
      //   "Listen to Location"
      //     travel-sample.inventory.airline
      //   "Eventing Storage"
      //     rr100.eventing.metadata
      //   Binding(s) - none
      //
      // Version 6.X
      //   "Source Bucket"
      //     travel-sample
      //   "MetaData Bucket"
      //     metadata
      //   Binding(s) - none
      
      function OnUpdate(doc, meta) {
          // ignore information we don't care about
          if (doc.type !== 'airline') return;
      
          var route_cnt = 0;       // we want to get the total routes per iata
          var airline = doc.iata;  // need a true variable as a SQL++ parameter
      
          var results =
              SELECT COUNT(*) AS cnt
              FROM `travel-sample`.`inventory`.`route`
              WHERE type = "route" AND airline = $airline;
      
          for (var item of results) {   // Stream results using 'for' iterator.
              route_cnt = item.cnt;
          }
          results.close();              // End the query and free resources held
      
          // Just log the KEY, AIRLINE and ROUTE_CNT it to the Application log
          log("key: " + meta.id + ", airline: "+doc.iata+", route_cnt: "+route_cnt);
      }
      UPDATE `travel-sample`.`inventory`.`airline` USE KEYS "airline_24" SET id = 24
      2021-07-19T07:37:39.237-07:00 [INFO] "key: airline_24, airline: AA, route_cnt: 2354"