BigQueryIO.Read (Google Cloud Dataflow SDK 1.9.1 API)

Google Cloud Dataflow SDK for Java, version 1.9.1

Warning: Cloud Dataflow SDK 1.x for Java is unsupported as of October 16, 2018. See Migrating from Cloud Dataflow SDK 1.x for Java for migration guidance.

Note: If you are using Cloud Dataflow SDK version 2.x, see the Apache Beam API reference documentation.

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 Object

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

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

  
   static class ExtractWordsFn extends DoFn<TableRow, String> {
     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 of TableRows.

  • Method Summary

    All Methods Static Methods Concrete Methods 

    Modifier and Type	Method and Description
    static BigQueryIO.Read.Bound	from(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	from(ValueProvider<String> tableSpec) Same as from(String), but with a ValueProvider.
    static BigQueryIO.Read.Bound	fromQuery(String query) Reads results received after executing the given query.
    static BigQueryIO.Read.Bound	fromQuery(ValueProvider<String> query) Same as from(String), but with a ValueProvider.
    static BigQueryIO.Read.Bound	named(String name) Returns a BigQueryIO.Read.Bound with the given 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

• • Method Detail

    • named

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

      Returns a BigQueryIO.Read.Bound with the given name. The BigQuery table or query to be read from has not yet been configured.

    • from

      public static BigQueryIO.Read.Bound from(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(ValueProvider<String> tableSpec)

      Same as from(String), but with a ValueProvider.

    • fromQuery

      public static BigQueryIO.Read.Bound fromQuery(String query)

      Reads results received after executing the given query.

    • fromQuery

      public static BigQueryIO.Read.Bound fromQuery(ValueProvider<String> query)

      Same as from(String), but with a ValueProvider.

    • 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.