BigQuery: rewrite simple app tutorial. (#950)

- Add region tags for needed dependencies.
- Use more relevant query from public datasets.

Author: tswast

bigquery/cloud-client/src/main/java/com/example/bigquery/SimpleApp.java

@@ -16,34 +16,36 @@
 
 package com.example.bigquery;
 
-// [START all]
-// [START imports]
+// [START bigquery_simple_app_all]
+// [START bigquery_simple_app_deps]
 import com.google.cloud.bigquery.BigQuery;
 import com.google.cloud.bigquery.BigQueryOptions;
 import com.google.cloud.bigquery.FieldValue;
+import com.google.cloud.bigquery.FieldValueList;
 import com.google.cloud.bigquery.Job;
 import com.google.cloud.bigquery.JobId;
 import com.google.cloud.bigquery.JobInfo;
 import com.google.cloud.bigquery.QueryJobConfiguration;
 import com.google.cloud.bigquery.QueryResponse;
 import com.google.cloud.bigquery.QueryResult;
-
 import java.util.List;
 import java.util.UUID;
-// [END imports]
+// [END bigquery_simple_app_deps]
 
 public class SimpleApp {
   public static void main(String... args) throws Exception {
-    // [START create_client]
+    // [START bigquery_simple_app_client]
     BigQuery bigquery = BigQueryOptions.getDefaultInstance().getService();
-    // [END create_client]
-    // [START run_query]
+    // [END bigquery_simple_app_client]
+    // [START bigquery_simple_app_query]
     QueryJobConfiguration queryConfig =
         QueryJobConfiguration.newBuilder(
-                "SELECT "
-                    + "APPROX_TOP_COUNT(corpus, 10) as title, "
-                    + "COUNT(*) as unique_words "
-                    + "FROM `bigquery-public-data.samples.shakespeare`;")
+          "SELECT "
+              + "CONCAT('https://stackoverflow.com/questions/', CAST(id as STRING)) as url, "
+              + "view_count "
+              + "FROM `bigquery-public-data.stackoverflow.posts_questions` "
+              + "WHERE tags like '%google-bigquery%' "
+              + "ORDER BY favorite_count DESC LIMIT 10")
             // Use standard SQL syntax for queries.
             // See: https://cloud.google.com/bigquery/sql-reference/
             .setUseLegacySql(false)
@@ -64,34 +66,21 @@ public static void main(String... args) throws Exception {
       // errors, not just the latest one.
       throw new RuntimeException(queryJob.getStatus().getError().toString());
     }
+    // [END bigquery_simple_app_query]
 
+    // [START bigquery_simple_app_print]
     // Get the results.
     QueryResponse response = bigquery.getQueryResults(jobId);
-    // [END run_query]
 
-    // [START print_results]
     QueryResult result = response.getResult();
 
     // Print all pages of the results.
-    while (result != null) {
-      for (List<FieldValue> row : result.iterateAll()) {
-        List<FieldValue> titles = row.get(0).getRepeatedValue();
-        System.out.println("titles:");
-
-        for (FieldValue titleValue : titles) {
-          List<FieldValue> titleRecord = titleValue.getRecordValue();
-          String title = titleRecord.get(0).getStringValue();
-          long uniqueWords = titleRecord.get(1).getLongValue();
-          System.out.printf("\t%s: %d\n", title, uniqueWords);
-        }
-
-        long uniqueWords = row.get(1).getLongValue();
-        System.out.printf("total unique words: %d\n", uniqueWords);
-      }
-
-      result = result.getNextPage();
+    for (FieldValueList row : result.iterateAll()) {
+      String url = row.get("url").getStringValue();
+      long viewCount = row.get("view_count").getLongValue();
+      System.out.printf("url: %s views: %d%n", url, viewCount);
     }
-    // [END print_results]
+    // [END bigquery_simple_app_print]
   }
 }
-// [END all]
+// [END bigquery_simple_app_all]

bigquery/cloud-client/src/test/java/com/example/bigquery/SimpleAppIT.java

@@ -18,15 +18,14 @@
 
 import static com.google.common.truth.Truth.assertThat;
 
+import java.io.ByteArrayOutputStream;
+import java.io.PrintStream;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.JUnit4;
 
-import java.io.ByteArrayOutputStream;
-import java.io.PrintStream;
-
 /** Tests for simple app sample. */
 @RunWith(JUnit4.class)
 @SuppressWarnings("checkstyle:abbreviationaswordinname")
@@ -50,6 +49,6 @@ public void tearDown() {
   public void testQuickstart() throws Exception {
     SimpleApp.main();
     String got = bout.toString();
-    assertThat(got).contains("hamlet");
+    assertThat(got).contains("views:");
   }
 }