com.google.cloud.dataflow.sdk.io

Class BigQueryIO.Read

java.lang.Object

com.google.cloud.dataflow.sdk.io.BigQueryIO.Read

Enclosing class:

BigQueryIO

public static class BigQueryIO.Read
extends java.lang.Object

A PTransform that reads from a BigQuery table and returns a PCollection<TableRow> containing each of the rows of the table.

Each TableRow record contains values indexed by column name. Here is a sample processing function which processes a "line" column from rows:

 static class ExtractWordsFn extends DoFn<TableRow, String> {
   @Override
   public void processElement(ProcessContext c) {
     // Get the "line" field of the TableRow object, split it into words, and emit them.
     TableRow row = c.element();
     String[] words = row.get("line").toString().split("[^a-zA-Z']+");
     for (String word : words) {
       if (!word.isEmpty()) {
         c.output(word);
       }
     }
   }
 }
 

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	BigQueryIO.Read.Bound A PTransform that reads from a BigQuery table and returns a bounded PCollection<TableRow>.

Constructor Summary

Constructors

Constructor and Description
BigQueryIO.Read()

Method Summary

Methods

Modifier and Type	Method and Description
static BigQueryIO.Read.Bound	from(java.lang.String tableSpec) Reads a BigQuery table specified as "[project_id]:[dataset_id].[table_id]" or "[dataset_id].[table_id]" for tables within the current project.
static BigQueryIO.Read.Bound	from(TableReference table) Reads a BigQuery table specified as a TableReference object.
static BigQueryIO.Read.Bound	named(java.lang.String name)
static BigQueryIO.Read.Bound	withoutValidation() Disables BigQuery table validation which is enabled by default.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

BigQueryIO.Read

public BigQueryIO.Read()

Method Detail

named

public static BigQueryIO.Read.Bound named(java.lang.String name)

from

public static BigQueryIO.Read.Bound from(java.lang.String tableSpec)

Reads a BigQuery table specified as "[project_id]:[dataset_id].[table_id]" or "[dataset_id].[table_id]" for tables within the current project.

from

public static BigQueryIO.Read.Bound from(TableReference table)

Reads a BigQuery table specified as a TableReference object.

withoutValidation

public static BigQueryIO.Read.Bound withoutValidation()

Disables BigQuery table validation which is enabled by default.