bigquery/examples_test.go

// Copyright 2016 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 bigquery_test

import (
	"context"
	"fmt"
	"os"
	"time"

	"cloud.google.com/go/bigquery"
	"google.golang.org/api/iterator"
)

func ExampleNewClient() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	_ = client // TODO: Use client.
}

func ExampleClient_Dataset() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	ds := client.Dataset("my_dataset")
	fmt.Println(ds)
}

func ExampleClient_DatasetInProject() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	ds := client.DatasetInProject("their-project-id", "their-dataset")
	fmt.Println(ds)
}

func ExampleClient_Datasets() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	it := client.Datasets(ctx)
	_ = it // TODO: iterate using Next or iterator.Pager.
}

func ExampleClient_DatasetsInProject() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	it := client.DatasetsInProject(ctx, "their-project-id")
	_ = it // TODO: iterate using Next or iterator.Pager.
}

func getJobID() string { return "" }

func ExampleClient_JobFromID() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	jobID := getJobID() // Get a job ID using Job.ID, the console or elsewhere.
	job, err := client.JobFromID(ctx, jobID)
	if err != nil {
		// TODO: Handle error.
	}
	fmt.Println(job.LastStatus()) // Display the job's status.
}

func ExampleClient_Jobs() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	it := client.Jobs(ctx)
	it.State = bigquery.Running // list only running jobs.
	_ = it                      // TODO: iterate using Next or iterator.Pager.
}

func ExampleNewGCSReference() {
	gcsRef := bigquery.NewGCSReference("gs://my-bucket/my-object")
	fmt.Println(gcsRef)
}

func ExampleClient_Query() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	q := client.Query("select name, num from t1")
	q.DefaultProjectID = "project-id"
	// TODO: set other options on the Query.
	// TODO: Call Query.Run or Query.Read.
}

func ExampleClient_Query_parameters() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	q := client.Query("select num from t1 where name = @user")
	q.Parameters = []bigquery.QueryParameter{
		{Name: "user", Value: "Elizabeth"},
	}
	// TODO: set other options on the Query.
	// TODO: Call Query.Run or Query.Read.
}

// This example demonstrates how to run a query job on a table
// with a customer-managed encryption key. The same
// applies to load and copy jobs as well.
func ExampleClient_Query_encryptionKey() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	q := client.Query("select name, num from t1")
	// TODO: Replace this key with a key you have created in Cloud KMS.
	keyName := "projects/P/locations/L/keyRings/R/cryptoKeys/K"
	q.DestinationEncryptionConfig = &bigquery.EncryptionConfig{KMSKeyName: keyName}
	// TODO: set other options on the Query.
	// TODO: Call Query.Run or Query.Read.
}

func ExampleQuery_Read() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	q := client.Query("select name, num from t1")
	it, err := q.Read(ctx)
	if err != nil {
		// TODO: Handle error.
	}
	_ = it // TODO: iterate using Next or iterator.Pager.
}

func ExampleQuery_Read_accelerated() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}

	// Enable Storage API usage for fetching data
	err = client.EnableStorageReadClient(ctx)
	if err != nil {
		// TODO: Handle error.
	}

	sql := fmt.Sprintf(`SELECT name, number, state FROM %s WHERE state = "CA"`, `bigquery-public-data.usa_names.usa_1910_current`)
	q := client.Query(sql)
	it, err := q.Read(ctx)
	if err != nil {
		// TODO: Handle error.
	}

	_ = it // TODO: iterate using Next or iterator.Pager.
}

func ExampleRowIterator_Next() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	q := client.Query("select name, num from t1")
	it, err := q.Read(ctx)
	if err != nil {
		// TODO: Handle error.
	}
	for {
		var row []bigquery.Value
		err := it.Next(&row)
		if err == iterator.Done {
			break
		}
		if err != nil {
			// TODO: Handle error.
		}
		fmt.Println(row)
	}
}

func ExampleRowIterator_Next_struct() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}

	type score struct {
		Name string
		Num  int
	}

	q := client.Query("select name, num from t1")
	it, err := q.Read(ctx)
	if err != nil {
		// TODO: Handle error.
	}
	for {
		var s score
		err := it.Next(&s)
		if err == iterator.Done {
			break
		}
		if err != nil {
			// TODO: Handle error.
		}
		fmt.Println(s)
	}
}

func ExampleJob_Read() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	q := client.Query("select name, num from t1")
	// Call Query.Run to get a Job, then call Read on the job.
	// Note: Query.Read is a shorthand for this.
	job, err := q.Run(ctx)
	if err != nil {
		// TODO: Handle error.
	}
	it, err := job.Read(ctx)
	if err != nil {
		// TODO: Handle error.
	}
	_ = it // TODO: iterate using Next or iterator.Pager.
}

func ExampleJob_Wait() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	ds := client.Dataset("my_dataset")
	job, err := ds.Table("t1").CopierFrom(ds.Table("t2")).Run(ctx)
	if err != nil {
		// TODO: Handle error.
	}
	status, err := job.Wait(ctx)
	if err != nil {
		// TODO: Handle error.
	}
	if status.Err() != nil {
		// TODO: Handle error.
	}
}

func ExampleJob_Config() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	ds := client.Dataset("my_dataset")
	job, err := ds.Table("t1").CopierFrom(ds.Table("t2")).Run(ctx)
	if err != nil {
		// TODO: Handle error.
	}
	jc, err := job.Config()
	if err != nil {
		// TODO: Handle error.
	}
	copyConfig := jc.(*bigquery.CopyConfig)
	fmt.Println(copyConfig.Dst, copyConfig.CreateDisposition)
}

func ExampleDataset_Create() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	ds := client.Dataset("my_dataset")
	if err := ds.Create(ctx, &bigquery.DatasetMetadata{Location: "EU"}); err != nil {
		// TODO: Handle error.
	}
}

func ExampleDataset_Delete() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	if err := client.Dataset("my_dataset").Delete(ctx); err != nil {
		// TODO: Handle error.
	}
}

func ExampleDataset_Metadata() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	md, err := client.Dataset("my_dataset").Metadata(ctx)
	if err != nil {
		// TODO: Handle error.
	}
	fmt.Println(md)
}

// This example illustrates how to perform a read-modify-write sequence on dataset
// metadata. Passing the metadata's ETag to the Update call ensures that the call
// will fail if the metadata was changed since the read.
func ExampleDataset_Update_readModifyWrite() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	ds := client.Dataset("my_dataset")
	md, err := ds.Metadata(ctx)
	if err != nil {
		// TODO: Handle error.
	}
	md2, err := ds.Update(ctx,
		bigquery.DatasetMetadataToUpdate{Name: "new " + md.Name},
		md.ETag)
	if err != nil {
		// TODO: Handle error.
	}
	fmt.Println(md2)
}

// To perform a blind write, ignoring the existing state (and possibly overwriting
// other updates), pass the empty string as the etag.
func ExampleDataset_Update_blindWrite() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	md, err := client.Dataset("my_dataset").Update(ctx, bigquery.DatasetMetadataToUpdate{Name: "blind"}, "")
	if err != nil {
		// TODO: Handle error.
	}
	fmt.Println(md)
}

func ExampleDataset_Table() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	// Table creates a reference to the table. It does not create the actual
	// table in BigQuery; to do so, use Table.Create.
	t := client.Dataset("my_dataset").Table("my_table")
	fmt.Println(t)
}

func ExampleDataset_Tables() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	it := client.Dataset("my_dataset").Tables(ctx)
	_ = it // TODO: iterate using Next or iterator.Pager.
}

func ExampleDatasetIterator_Next() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	it := client.Datasets(ctx)
	for {
		ds, err := it.Next()
		if err == iterator.Done {
			break
		}
		if err != nil {
			// TODO: Handle error.
		}
		fmt.Println(ds)
	}
}

func ExampleInferSchema() {
	type Item struct {
		Name  string
		Size  float64
		Count int
	}
	schema, err := bigquery.InferSchema(Item{})
	if err != nil {
		fmt.Println(err)
		// TODO: Handle error.
	}
	for _, fs := range schema {
		fmt.Println(fs.Name, fs.Type)
	}
	// Output:
	// Name STRING
	// Size FLOAT
	// Count INTEGER
}

func ExampleInferSchema_tags() {
	type Item struct {
		Name     string
		Size     float64
		Count    int    `bigquery:"number"`
		Secret   []byte `bigquery:"-"`
		Optional bigquery.NullBool
		OptBytes []byte `bigquery:",nullable"`
	}
	schema, err := bigquery.InferSchema(Item{})
	if err != nil {
		fmt.Println(err)
		// TODO: Handle error.
	}
	for _, fs := range schema {
		fmt.Println(fs.Name, fs.Type, fs.Required)
	}
	// Output:
	// Name STRING true
	// Size FLOAT true
	// number INTEGER true
	// Optional BOOLEAN false
	// OptBytes BYTES false
}

func ExampleTable_Create() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	t := client.Dataset("my_dataset").Table("new-table")
	if err := t.Create(ctx, nil); err != nil {
		// TODO: Handle error.
	}
}

// Initialize a new table by passing TableMetadata to Table.Create.
func ExampleTable_Create_initialize() {
	ctx := context.Background()
	// Infer table schema from a Go type.
	schema, err := bigquery.InferSchema(Item{})
	if err != nil {
		// TODO: Handle error.
	}
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	t := client.Dataset("my_dataset").Table("new-table")
	if err := t.Create(ctx,
		&bigquery.TableMetadata{
			Name:           "My New Table",
			Schema:         schema,
			ExpirationTime: time.Now().Add(24 * time.Hour),
		}); err != nil {
		// TODO: Handle error.
	}
}

// This example demonstrates how to create a table with
// a customer-managed encryption key.
func ExampleTable_Create_encryptionKey() {
	ctx := context.Background()
	// Infer table schema from a Go type.
	schema, err := bigquery.InferSchema(Item{})
	if err != nil {
		// TODO: Handle error.
	}
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	t := client.Dataset("my_dataset").Table("new-table")

	// TODO: Replace this key with a key you have created in Cloud KMS.
	keyName := "projects/P/locations/L/keyRings/R/cryptoKeys/K"
	if err := t.Create(ctx,
		&bigquery.TableMetadata{
			Name:             "My New Table",
			Schema:           schema,
			EncryptionConfig: &bigquery.EncryptionConfig{KMSKeyName: keyName},
		}); err != nil {
		// TODO: Handle error.
	}
}

func ExampleTable_Delete() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	if err := client.Dataset("my_dataset").Table("my_table").Delete(ctx); err != nil {
		// TODO: Handle error.
	}
}

func ExampleTable_Metadata() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	md, err := client.Dataset("my_dataset").Table("my_table").Metadata(ctx)
	if err != nil {
		// TODO: Handle error.
	}
	fmt.Println(md)
}

func ExampleTable_Inserter() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	ins := client.Dataset("my_dataset").Table("my_table").Inserter()
	_ = ins // TODO: Use ins.
}

func ExampleTable_Inserter_options() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	ins := client.Dataset("my_dataset").Table("my_table").Inserter()
	ins.SkipInvalidRows = true
	ins.IgnoreUnknownValues = true
	_ = ins // TODO: Use ins.
}

func ExampleTable_CopierFrom() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	ds := client.Dataset("my_dataset")
	c := ds.Table("combined").CopierFrom(ds.Table("t1"), ds.Table("t2"))
	c.WriteDisposition = bigquery.WriteTruncate
	// TODO: set other options on the Copier.
	job, err := c.Run(ctx)
	if err != nil {
		// TODO: Handle error.
	}
	status, err := job.Wait(ctx)
	if err != nil {
		// TODO: Handle error.
	}
	if status.Err() != nil {
		// TODO: Handle error.
	}
}

func ExampleTable_ExtractorTo() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	gcsRef := bigquery.NewGCSReference("gs://my-bucket/my-object")
	gcsRef.FieldDelimiter = ":"
	// TODO: set other options on the GCSReference.
	ds := client.Dataset("my_dataset")
	extractor := ds.Table("my_table").ExtractorTo(gcsRef)
	extractor.DisableHeader = true
	// TODO: set other options on the Extractor.
	job, err := extractor.Run(ctx)
	if err != nil {
		// TODO: Handle error.
	}
	status, err := job.Wait(ctx)
	if err != nil {
		// TODO: Handle error.
	}
	if status.Err() != nil {
		// TODO: Handle error.
	}
}

func ExampleTable_LoaderFrom() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	gcsRef := bigquery.NewGCSReference("gs://my-bucket/my-object")
	gcsRef.AllowJaggedRows = true
	gcsRef.MaxBadRecords = 5
	gcsRef.Schema = schema
	// TODO: set other options on the GCSReference.
	ds := client.Dataset("my_dataset")
	loader := ds.Table("my_table").LoaderFrom(gcsRef)
	loader.CreateDisposition = bigquery.CreateNever
	// TODO: set other options on the Loader.
	job, err := loader.Run(ctx)
	if err != nil {
		// TODO: Handle error.
	}
	status, err := job.Wait(ctx)
	if err != nil {
		// TODO: Handle error.
	}
	if status.Err() != nil {
		// TODO: Handle error.
	}
}

func ExampleTable_LoaderFrom_reader() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	f, err := os.Open("data.csv")
	if err != nil {
		// TODO: Handle error.
	}
	rs := bigquery.NewReaderSource(f)
	rs.AllowJaggedRows = true
	rs.MaxBadRecords = 5
	rs.Schema = schema
	// TODO: set other options on the GCSReference.
	ds := client.Dataset("my_dataset")
	loader := ds.Table("my_table").LoaderFrom(rs)
	loader.CreateDisposition = bigquery.CreateNever
	// TODO: set other options on the Loader.
	job, err := loader.Run(ctx)
	if err != nil {
		// TODO: Handle error.
	}
	status, err := job.Wait(ctx)
	if err != nil {
		// TODO: Handle error.
	}
	if status.Err() != nil {
		// TODO: Handle error.
	}
}

func ExampleTable_Read() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	it := client.Dataset("my_dataset").Table("my_table").Read(ctx)
	_ = it // TODO: iterate using Next or iterator.Pager.
}

// This example illustrates how to perform a read-modify-write sequence on table
// metadata. Passing the metadata's ETag to the Update call ensures that the call
// will fail if the metadata was changed since the read.
func ExampleTable_Update_readModifyWrite() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	t := client.Dataset("my_dataset").Table("my_table")
	md, err := t.Metadata(ctx)
	if err != nil {
		// TODO: Handle error.
	}
	md2, err := t.Update(ctx,
		bigquery.TableMetadataToUpdate{Name: "new " + md.Name},
		md.ETag)
	if err != nil {
		// TODO: Handle error.
	}
	fmt.Println(md2)
}

// To perform a blind write, ignoring the existing state (and possibly overwriting
// other updates), pass the empty string as the etag.
func ExampleTable_Update_blindWrite() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	t := client.Dataset("my_dataset").Table("my_table")
	tm, err := t.Update(ctx, bigquery.TableMetadataToUpdate{
		Description: "my favorite table",
	}, "")
	if err != nil {
		// TODO: Handle error.
	}
	fmt.Println(tm)
}

func ExampleTableIterator_Next() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	it := client.Dataset("my_dataset").Tables(ctx)
	for {
		t, err := it.Next()
		if err == iterator.Done {
			break
		}
		if err != nil {
			// TODO: Handle error.
		}
		fmt.Println(t)
	}
}

type Item struct {
	Name  string
	Size  float64
	Count int
}

// Save implements the ValueSaver interface.
func (i *Item) Save() (map[string]bigquery.Value, string, error) {
	return map[string]bigquery.Value{
		"Name":  i.Name,
		"Size":  i.Size,
		"Count": i.Count,
	}, "", nil
}

func ExampleInserter_Put() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	ins := client.Dataset("my_dataset").Table("my_table").Inserter()
	// Item implements the ValueSaver interface.
	items := []*Item{
		{Name: "n1", Size: 32.6, Count: 7},
		{Name: "n2", Size: 4, Count: 2},
		{Name: "n3", Size: 101.5, Count: 1},
	}
	if err := ins.Put(ctx, items); err != nil {
		// TODO: Handle error.
	}
}

var schema bigquery.Schema

func ExampleInserter_Put_structSaver() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	ins := client.Dataset("my_dataset").Table("my_table").Inserter()

	type score struct {
		Name string
		Num  int
	}

	// Assume schema holds the table's schema.
	savers := []*bigquery.StructSaver{
		{Struct: score{Name: "n1", Num: 12}, Schema: schema, InsertID: "id1"},
		{Struct: score{Name: "n2", Num: 31}, Schema: schema, InsertID: "id2"},
		{Struct: score{Name: "n3", Num: 7}, Schema: schema, InsertID: "id3"},
	}
	if err := ins.Put(ctx, savers); err != nil {
		// TODO: Handle error.
	}
}

func ExampleInserter_Put_struct() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}
	ins := client.Dataset("my_dataset").Table("my_table").Inserter()

	type score struct {
		Name string
		Num  int
	}
	scores := []score{
		{Name: "n1", Num: 12},
		{Name: "n2", Num: 31},
		{Name: "n3", Num: 7},
	}
	// Schema is inferred from the score type.
	if err := ins.Put(ctx, scores); err != nil {
		// TODO: Handle error.
	}
}

func ExampleInserter_Put_valuesSaver() {
	ctx := context.Background()
	client, err := bigquery.NewClient(ctx, "project-id")
	if err != nil {
		// TODO: Handle error.
	}

	ins := client.Dataset("my_dataset").Table("my_table").Inserter()

	var vss []*bigquery.ValuesSaver
	for i, name := range []string{"n1", "n2", "n3"} {
		// Assume schema holds the table's schema.
		vss = append(vss, &bigquery.ValuesSaver{
			Schema:   schema,
			InsertID: name,
			Row:      []bigquery.Value{name, int64(i)},
		})
	}

	if err := ins.Put(ctx, vss); err != nil {
		// TODO: Handle error.
	}
}