Examples using QueryRequest API

You can use QueryRequest API and apply SQL functions to fetch data from a NoSQL table.

• Java
• Python
• Go
• Node.js
• C#

To execute your query, you use the NoSQLHandle.query() API.

Download the full code SQLFunctions.java from the examples here.

 //Fetch rows from the table
private static void fetchRows(NoSQLHandle handle,String sqlstmt) throws Exception {
   try (
      QueryRequest queryRequest = new QueryRequest().setStatement(sqlstmt);
      QueryIterableResult results = handle.queryIterable(queryRequest)){
      for (MapValue res : results) {
         System.out.println("\t" + res);
      }
   }
} 

String ts_func1="SELECT timestamp_add(bag.bagInfo.flightLegs[0].estimatedArrival, \"5 minutes\")"+
                         " AS ARRIVAL_TIME FROM BaggageInfo bag WHERE ticketNo=1762341772625";
System.out.println("Using timestamp_add function ");
fetchRows(handle,ts_func1);
String ts_func2="SELECT $s.ticketno, $bagInfo.bagArrivalDate, $flightLeg.flightDate, "+
                "get_duration(timestamp_diff($bagInfo.bagArrivalDate, $flightLeg.flightDate)) AS diff "+
                 "FROM baggageinfo $s, $s.bagInfo[] AS $bagInfo, $bagInfo.flightLegs[] AS $flightLeg "+
                 "WHERE ticketNo=1762344493810";
System.out.println("Using get_duration and timestamp_diff function ");
fetchRows(handle,ts_func2);

To execute your query use the borneo.NoSQLHandle.query() method.

Download the full code SQLFunctions.py from the examples here.

# Fetch data from the table
def fetch_data(handle,sqlstmt):
   request = QueryRequest().set_statement(sqlstmt)
   print('Query results for: ' + sqlstmt)
   result = handle.query(request)
   for r in result.get_results():
      print('\t' + str(r))  

 ts_func1 = '''SELECT timestamp_add(bag.bagInfo.flightLegs[0].estimatedArrival, "5 minutes")
                 AS ARRIVAL_TIME FROM BaggageInfo bag WHERE ticketNo=1762341772625'''
print('Using timestamp_add function:')
fetch_data(handle,ts_func1)

ts_func2 = '''SELECT $s.ticketno, $bagInfo.bagArrivalDate, $flightLeg.flightDate,
              get_duration(timestamp_diff($bagInfo.bagArrivalDate, $flightLeg.flightDate)) AS diff
              FROM baggageinfo $s,
              $s.bagInfo[] AS $bagInfo, $bagInfo.flightLegs[] AS $flightLeg
              WHERE ticketNo=1762344493810'''
print('Using get_duration and timestamp_diff function:')
fetch_data(handle,ts_func2)

To execute a query use the Client.Query function.

Download the full code SQLFunctions.go from the examples here.

 //fetch data from the table
func fetchData(client *nosqldb.Client, err error, tableName string, querystmt string)(){
   prepReq := &nosqldb.PrepareRequest{
		Statement: querystmt,
   }
   prepRes, err := client.Prepare(prepReq)
   if err != nil {
      fmt.Printf("Prepare failed: %v\n", err)
      return
   }
   queryReq := &nosqldb.QueryRequest{
		 PreparedStatement: &prepRes.PreparedStatement,   }
   var results []*types.MapValue
   for {
      queryRes, err := client.Query(queryReq)
      if err != nil {
         fmt.Printf("Query failed: %v\n", err)
  	return
      }
      res, err := queryRes.GetResults()
      if err != nil {
         fmt.Printf("GetResults() failed: %v\n", err)
  	return
      }
      results = append(results, res...)
      if queryReq.IsDone() {
         break
      }
   }
   for i, r := range results {
      fmt.Printf("\t%d: %s\n", i+1, jsonutil.AsJSON(r.Map()))
   }
} 

ts_func1 := `SELECT timestamp_add(bag.bagInfo.flightLegs[0].estimatedArrival, "5 minutes")
                AS ARRIVAL_TIME FROM BaggageInfo bag WHERE ticketNo=1762341772625`
fmt.Printf("Using timestamp_add function::\n")
fetchData(client, err,tableName,ts_func1)

ts_func2 := `SELECT $s.ticketno, $bagInfo.bagArrivalDate, $flightLeg.flightDate,
             get_duration(timestamp_diff($bagInfo.bagArrivalDate, $flightLeg.flightDate)) AS diff
             FROM baggageinfo $s,
             $s.bagInfo[] AS $bagInfo, $bagInfo.flightLegs[] AS $flightLeg
             WHERE ticketNo=1762344493810`
fmt.Printf("Using get_duration and timestamp_diff function:\n")
fetchData(client, err,tableName,ts_func2)

To execute a query use query method.

JavaScript: Download the full code SQLFunctions.js from the examples here.

  //fetches data from the table
async function fetchData(handle,querystmt) {
   const opt = {};
   try {
      do {
         const result = await handle.query(querystmt, opt);
         for(let row of result.rows) {
            console.log('  %O', row);
         }
         opt.continuationKey = result.continuationKey;
      } while(opt.continuationKey);
   } catch(error) {
      console.error('  Error: ' + error.message);
   }
}

TypeScript: Download the full code SQLFunctions.ts from the examples here.

interface StreamInt {
   acct_Id: Integer;
   profile_name: String;
   account_expiry: TIMESTAMP;
   acct_data: JSON;
}

/* fetches data from the table */
async function fetchData(handle: NoSQLClient,querystmt: string) {
   const opt = {};
   try {
      do {
         const result = await handle.query<StreamInt>(querystmt, opt);
         for(let row of result.rows) {
            console.log('  %O', row);
         }
         opt.continuationKey = result.continuationKey;
      } while(opt.continuationKey);
   } catch(error) {
      console.error('  Error: ' + error.message);
   }
}

const ts_func1 = `SELECT timestamp_add(bag.bagInfo.flightLegs[0].estimatedArrival, "5 minutes")
                  AS ARRIVAL_TIME FROM BaggageInfo bag WHERE ticketNo=1762341772625`
console.log("Using timestamp_add function:");
await fetchData(handle,ts_func1);

const ts_func2 = `SELECT $s.ticketno, $bagInfo.bagArrivalDate, $flightLeg.flightDate,
                  get_duration(timestamp_diff($bagInfo.bagArrivalDate, $flightLeg.flightDate)) AS diff
                  FROM baggageinfo $s,
                  $s.bagInfo[] AS $bagInfo, $bagInfo.flightLegs[] AS $flightLeg
                  WHERE ticketNo=1762344493810`
console.log("Using get_duration and timestamp_diff function:");
await fetchData(handle,ts_func2);

To execute a query, you may call QueryAsync method or call GetQueryAsyncEnumerable method and iterate over the resulting async enumerable.

Download the full code SQLFunctions.cs from the examples here.

private static async Task fetchData(NoSQLClient client,String querystmt){
   var queryEnumerable = client.GetQueryAsyncEnumerable(querystmt);
   await DoQuery(queryEnumerable);
}

private static async Task DoQuery(IAsyncEnumerable<QueryResult<RecordValue>> queryEnumerable){
   Console.WriteLine("  Query results:");
   await foreach (var result in queryEnumerable) {
      foreach (var row in result.Rows)
      {
         Console.WriteLine();
         Console.WriteLine(row.ToJsonString());
      }
   }
} 

private const string ts_func1 =@"SELECT timestamp_add(bag.bagInfo.flightLegs[0].estimatedArrival, ""5 minutes"")
                                       AS ARRIVAL_TIME FROM BaggageInfo bag WHERE ticketNo=1762341772625";
Console.WriteLine("\nUsing timestamp_add function!");
await fetchData(client,ts_func1);

private const string ts_func2 =@"SELECT $s.ticketno, $bagInfo.bagArrivalDate, $flightLeg.flightDate,
                                       get_duration(timestamp_diff($bagInfo.bagArrivalDate, $flightLeg.flightDate)) AS diff
                                       FROM baggageinfo $s,
                                       $s.bagInfo[] AS $bagInfo, $bagInfo.flightLegs[] AS $flightLeg
                                       WHERE ticketNo=1762344493810";
Console.WriteLine("\nUsing get_duration and timestamp_diff function!");
await fetchData(client,ts_func2);