Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Browse files
Browse the repository at this point in the history
docs(samples): add query legacy large results (#594)
- Loading branch information
Praful Makani
committed
Jul 24, 2020
1 parent
ef757ad
commit 4787dd0
Showing
2 changed files
with
140 additions
and
0 deletions.
There are no files selected for viewing
68 changes: 68 additions & 0 deletions
68
samples/snippets/src/main/java/com/example/bigquery/QueryLargeResults.java
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,68 @@ | ||
/* | ||
* Copyright 2020 Google LLC | ||
* | ||
* Licensed under the Apache License, Version 2.0 (the "License"); | ||
* you may not use this file except in compliance with the License. | ||
* You may obtain a copy of the License at | ||
* | ||
* http://www.apache.org/licenses/LICENSE-2.0 | ||
* | ||
* Unless required by applicable law or agreed to in writing, software | ||
* distributed under the License is distributed on an "AS IS" BASIS, | ||
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | ||
* See the License for the specific language governing permissions and | ||
* limitations under the License. | ||
*/ | ||
|
||
package com.example.bigquery; | ||
|
||
// [START bigquery_query_legacy_large_results] | ||
import com.google.cloud.bigquery.BigQuery; | ||
import com.google.cloud.bigquery.BigQueryException; | ||
import com.google.cloud.bigquery.BigQueryOptions; | ||
import com.google.cloud.bigquery.QueryJobConfiguration; | ||
import com.google.cloud.bigquery.TableId; | ||
import com.google.cloud.bigquery.TableResult; | ||
|
||
// Sample to run query with large results and save the results to a table. | ||
public class QueryLargeResults { | ||
|
||
public static void runQueryLargeResults() { | ||
// TODO(developer): Replace these variables before running the sample. | ||
String destinationDataset = "MY_DESTINATION_DATASET_NAME"; | ||
String destinationTable = "MY_DESTINATION_TABLE_NAME"; | ||
String query = "SELECT corpus FROM [bigquery-public-data:samples.shakespeare] GROUP BY corpus;"; | ||
queryLargeResults(destinationDataset, destinationTable, query); | ||
} | ||
|
||
public static void queryLargeResults( | ||
String destinationDataset, String destinationTable, String query) { | ||
try { | ||
// Initialize client that will be used to send requests. This client only needs to be created | ||
// once, and can be reused for multiple requests. | ||
BigQuery bigquery = BigQueryOptions.getDefaultInstance().getService(); | ||
|
||
QueryJobConfiguration queryConfig = | ||
// To use legacy SQL syntax, set useLegacySql to true. | ||
QueryJobConfiguration.newBuilder(query) | ||
.setUseLegacySql(true) | ||
// Save the results of the query to a permanent table. | ||
.setDestinationTable(TableId.of(destinationDataset, destinationTable)) | ||
// Allow results larger than the maximum response size. | ||
// If true, a destination table must be set. | ||
.setAllowLargeResults(true) | ||
.build(); | ||
|
||
TableResult results = bigquery.query(queryConfig); | ||
|
||
results | ||
.iterateAll() | ||
.forEach(row -> row.forEach(val -> System.out.printf("%s,", val.toString()))); | ||
|
||
System.out.println("Query large results performed successfully."); | ||
} catch (BigQueryException | InterruptedException e) { | ||
System.out.println("Query not performed \n" + e.toString()); | ||
} | ||
} | ||
} | ||
// [END bigquery_query_legacy_large_results] |
72 changes: 72 additions & 0 deletions
72
samples/snippets/src/test/java/com/example/bigquery/QueryLargeResultsIT.java
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,72 @@ | ||
/* | ||
* Copyright 2020 Google LLC | ||
* | ||
* Licensed under the Apache License, Version 2.0 (the "License"); | ||
* you may not use this file except in compliance with the License. | ||
* You may obtain a copy of the License at | ||
* | ||
* http://www.apache.org/licenses/LICENSE-2.0 | ||
* | ||
* Unless required by applicable law or agreed to in writing, software | ||
* distributed under the License is distributed on an "AS IS" BASIS, | ||
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | ||
* See the License for the specific language governing permissions and | ||
* limitations under the License. | ||
*/ | ||
|
||
package com.example.bigquery; | ||
|
||
import static com.google.common.truth.Truth.assertThat; | ||
import static junit.framework.TestCase.assertNotNull; | ||
|
||
import java.io.ByteArrayOutputStream; | ||
import java.io.PrintStream; | ||
import java.util.UUID; | ||
import org.junit.After; | ||
import org.junit.Before; | ||
import org.junit.BeforeClass; | ||
import org.junit.Test; | ||
|
||
public class QueryLargeResultsIT { | ||
|
||
private String tableName; | ||
private ByteArrayOutputStream bout; | ||
private PrintStream out; | ||
|
||
private static final String BIGQUERY_DATASET_NAME = requireEnvVar("BIGQUERY_DATASET_NAME"); | ||
|
||
private static String requireEnvVar(String varName) { | ||
String value = System.getenv(varName); | ||
assertNotNull( | ||
"Environment variable " + varName + " is required to perform these tests.", | ||
System.getenv(varName)); | ||
return value; | ||
} | ||
|
||
@BeforeClass | ||
public static void checkRequirements() { | ||
requireEnvVar("BIGQUERY_DATASET_NAME"); | ||
} | ||
|
||
@Before | ||
public void setUp() { | ||
tableName = "QUERY_LARGE_RESULT_TABLE_TEST" + UUID.randomUUID().toString().substring(0, 8); | ||
bout = new ByteArrayOutputStream(); | ||
out = new PrintStream(bout); | ||
System.setOut(out); | ||
} | ||
|
||
@After | ||
public void tearDown() { | ||
// Clean up | ||
DeleteTable.deleteTable(BIGQUERY_DATASET_NAME, tableName); | ||
System.setOut(null); | ||
} | ||
|
||
@Test | ||
public void testQueryLargeResults() { | ||
String query = "SELECT corpus FROM [bigquery-public-data:samples.shakespeare] GROUP BY corpus;"; | ||
QueryLargeResults.queryLargeResults(BIGQUERY_DATASET_NAME, tableName, query); | ||
assertThat(bout.toString()).contains("Query large results performed successfully."); | ||
} | ||
} |