Java Code Examples for com.google.cloud.spanner.DatabaseClient#write()

/**
 * Sends a QueueMessage to the spanner queue table
 *
 * <p>Example of sending data to a queue.
 *
 * <pre>{@code
 * MyProto myProto = MyProto.newBuilder().setMessage("My-Message").build();
 *
 * try {
 *   Queue.send(dbClient, queueName, "myKey", ByteArray.copyFrom(myProto.toByteArray()));
 * } catch (SpannerException e) {
 *   log.error("Could not write message to Queue", e);
 * }
 * }</pre>
 *
 * @param dbClient the Spanner database client
 * @param queueName the name of the queue to be polled
 * @param key the name used to partition the passed value for storage and lookup
 * @param value the message payload
 * @return Timestamp the timestamp that the message was written
 */
public static Timestamp send(DatabaseClient dbClient, String queueName, String key, byte[] value)
    throws SpannerException {
  Preconditions.checkNotNull(dbClient);
  Preconditions.checkNotNull(queueName);
  Preconditions.checkNotNull(key);
  Preconditions.checkNotNull(value);

  final List<Mutation> mutations = new ArrayList<>();
  mutations.add(
      Mutation.newInsertBuilder(queueName)
          .set("MessageId")
          .to(UUID.randomUUID().toString())
          .set("Key")
          .to(key)
          .set("Payload")
          .to(ByteArray.copyFrom(value))
          .set("Ack")
          .to(false)
          .set("Timestamp")
          .to(Value.COMMIT_TIMESTAMP)
          .build());

  return dbClient.write(mutations);
}
 

static void writeExampleDataWithTimestamp(DatabaseClient dbClient) {
  List<Mutation> mutations = new ArrayList<>();
  for (Performance performance : PERFORMANCES) {
    mutations.add(
        Mutation.newInsertBuilder("Performances")
            .set("SingerId")
            .to(performance.singerId)
            .set("VenueId")
            .to(performance.venueId)
            .set("EventDate")
            .to(performance.eventDate)
            .set("Revenue")
            .to(performance.revenue)
            .set("LastUpdateTime")
            .to(Value.COMMIT_TIMESTAMP)
            .build());
  }
  dbClient.write(mutations);
}
 

static void writeExampleData(DatabaseClient dbClient) {
  List<Mutation> mutations = new ArrayList<>();
  for (Singer singer : SINGERS) {
    mutations.add(
        Mutation.newInsertBuilder("Singers")
            .set("SingerId")
            .to(singer.singerId)
            .set("FirstName")
            .to(singer.firstName)
            .set("LastName")
            .to(singer.lastName)
            .build());
  }
  for (Album album : ALBUMS) {
    mutations.add(
        Mutation.newInsertBuilder("Albums")
            .set("SingerId")
            .to(album.singerId)
            .set("AlbumId")
            .to(album.albumId)
            .set("AlbumTitle")
            .to(album.albumTitle)
            .build());
  }
  dbClient.write(mutations);
}
 

static void deleteExampleData(DatabaseClient dbClient) {
  List<Mutation> mutations = new ArrayList<>();

  // KeySet.Builder can be used to delete a specific set of rows.
  // Delete the Albums with the key values (2,1) and (2,3).
  mutations.add(
      Mutation.delete(
          "Albums", KeySet.newBuilder().addKey(Key.of(2, 1)).addKey(Key.of(2, 3)).build()));

  // KeyRange can be used to delete rows with a key in a specific range.
  // Delete a range of rows where the column key is >=3 and <5
  mutations.add(
      Mutation.delete("Singers", KeySet.range(KeyRange.closedOpen(Key.of(3), Key.of(5)))));

  // KeySet.all() can be used to delete all the rows in a table.
  // Delete remaining Singers rows, which will also delete the remaining Albums rows since it was
  // defined with ON DELETE CASCADE.
  mutations.add(Mutation.delete("Singers", KeySet.all()));

  dbClient.write(mutations);
  System.out.printf("Records deleted.\n");
}
 

static void update(DatabaseClient dbClient) {
  // Mutation can be used to update/insert/delete a single row in a table. Here we use
  // newUpdateBuilder to create update mutations.
  List<Mutation> mutations =
      Arrays.asList(
          Mutation.newUpdateBuilder("Albums")
              .set("SingerId")
              .to(1)
              .set("AlbumId")
              .to(1)
              .set("MarketingBudget")
              .to(100000)
              .build(),
          Mutation.newUpdateBuilder("Albums")
              .set("SingerId")
              .to(2)
              .set("AlbumId")
              .to(2)
              .set("MarketingBudget")
              .to(500000)
              .build());
  // This writes all the mutations to Cloud Spanner atomically.
  dbClient.write(mutations);
}
 

static void writeStructExampleData(DatabaseClient dbClient) {
  final List<Singer> singers =
      Arrays.asList(
          new Singer(6, "Elena", "Campbell"),
          new Singer(7, "Gabriel", "Wright"),
          new Singer(8, "Benjamin", "Martinez"),
          new Singer(9, "Hannah", "Harris"));

  List<Mutation> mutations = new ArrayList<>();
  for (Singer singer : singers) {
    mutations.add(
        Mutation.newInsertBuilder("Singers")
            .set("SingerId")
            .to(singer.singerId)
            .set("FirstName")
            .to(singer.firstName)
            .set("LastName")
            .to(singer.lastName)
            .build());
  }
  dbClient.write(mutations);
  System.out.println("Inserted example data for struct parameter queries.");
}
 

static void updateWithTimestamp(DatabaseClient dbClient) {
  // Mutation can be used to update/insert/delete a single row in a table. Here we use
  // newUpdateBuilder to create update mutations.
  List<Mutation> mutations =
      Arrays.asList(
          Mutation.newUpdateBuilder("Albums")
              .set("SingerId")
              .to(1)
              .set("AlbumId")
              .to(1)
              .set("MarketingBudget")
              .to(1000000)
              .set("LastUpdateTime")
              .to(Value.COMMIT_TIMESTAMP)
              .build(),
          Mutation.newUpdateBuilder("Albums")
              .set("SingerId")
              .to(2)
              .set("AlbumId")
              .to(2)
              .set("MarketingBudget")
              .to(750000)
              .set("LastUpdateTime")
              .to(Value.COMMIT_TIMESTAMP)
              .build());
  // This writes all the mutations to Cloud Spanner atomically.
  dbClient.write(mutations);
}
 

static void writeDatatypesData(DatabaseClient dbClient) {
  List<Mutation> mutations = new ArrayList<>();
  for (Venue venue : VENUES) {
    mutations.add(
        Mutation.newInsertBuilder("Venues")
            .set("VenueId")
            .to(venue.venueId)
            .set("VenueName")
            .to(venue.venueName)
            .set("VenueInfo")
            .to(venue.venueInfo)
            .set("Capacity")
            .to(venue.capacity)
            .set("AvailableDates")
            .to(venue.availableDates)
            .set("LastContactDate")
            .to(venue.lastContactDate)
            .set("OutdoorVenue")
            .to(venue.outdoorVenue)
            .set("PopularityScore")
            .to(venue.popularityScore)
            .set("LastUpdateTime")
            .to(Value.COMMIT_TIMESTAMP)
            .build());
  }
  dbClient.write(mutations);
}