public static class BigQueryIO.Read extends PTransform<PBegin,PCollection<TableRow>>
BigQueryIO.read()
.name
Modifier and Type | Method and Description |
---|---|
PCollection<TableRow> |
expand(PBegin input)
Override this method to specify how this
PTransform should be expanded on the given
InputT . |
BigQueryIO.Read |
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. |
BigQueryIO.Read |
from(TableReference table)
Read from table specified by a
TableReference . |
BigQueryIO.Read |
from(ValueProvider<java.lang.String> tableSpec)
Same as
from(String) , but with a ValueProvider . |
BigQueryIO.Read |
fromQuery(java.lang.String query)
Reads results received after executing the given query.
|
BigQueryIO.Read |
fromQuery(ValueProvider<java.lang.String> query)
Same as
fromQuery(String) , but with a ValueProvider . |
TableReference |
getTable()
Returns the table to read, or
null if reading from a query instead. |
ValueProvider<TableReference> |
getTableProvider()
Returns the table to read, or
null if reading from a query instead. |
void |
populateDisplayData(DisplayData.Builder builder)
Register display data for the given transform or component.
|
BigQueryIO.Read |
usingStandardSql()
Enables BigQuery's Standard SQL dialect when reading from a query.
|
BigQueryIO.Read |
withoutResultFlattening()
Disable flattening of
query results.
|
BigQueryIO.Read |
withoutValidation()
Disable validation that the table exists or the query succeeds prior to pipeline submission.
|
BigQueryIO.Read |
withTemplateCompatibility()
Use new template-compatible source implementation.
|
compose, getAdditionalInputs, getDefaultOutputCoder, getDefaultOutputCoder, getDefaultOutputCoder, getKindString, getName, toString, validate
public PCollection<TableRow> expand(PBegin input)
PTransform
PTransform
should be expanded on the given
InputT
.
NOTE: This method should not be called directly. Instead apply the PTransform
should
be applied to the InputT
using the apply
method.
Composite transforms, which are defined in terms of other transforms, should return the output of one of the composed transforms. Non-composite transforms, which do not apply any transforms internally, should return a new unbound output and register evaluators (via backend-specific registration methods).
expand
in class PTransform<PBegin,PCollection<TableRow>>
public void populateDisplayData(DisplayData.Builder builder)
PTransform
populateDisplayData(DisplayData.Builder)
is invoked by Pipeline runners to collect
display data via DisplayData.from(HasDisplayData)
. Implementations may call super.populateDisplayData(builder)
in order to register display data in the current namespace,
but should otherwise use subcomponent.populateDisplayData(builder)
to use the namespace
of the subcomponent.
By default, does not register any display data. Implementors may override this method to provide their own display data.
populateDisplayData
in interface HasDisplayData
populateDisplayData
in class PTransform<PBegin,PCollection<TableRow>>
builder
- The builder to populate with display data.HasDisplayData
@Nullable public ValueProvider<TableReference> getTableProvider()
null
if reading from a query instead.@Nullable public TableReference getTable()
null
if reading from a query instead.public BigQueryIO.Read from(java.lang.String tableSpec)
"[project_id]:[dataset_id].[table_id]"
or "[dataset_id].[table_id]"
for tables within the current project.public BigQueryIO.Read from(ValueProvider<java.lang.String> tableSpec)
from(String)
, but with a ValueProvider
.public BigQueryIO.Read from(TableReference table)
TableReference
.public BigQueryIO.Read fromQuery(java.lang.String query)
By default, the query results will be flattened -- see "flattenResults" in the Jobs documentation for
more information. To disable flattening, use withoutResultFlattening()
.
By default, the query will use BigQuery's legacy SQL dialect. To use the BigQuery Standard
SQL dialect, use usingStandardSql()
.
public BigQueryIO.Read fromQuery(ValueProvider<java.lang.String> query)
fromQuery(String)
, but with a ValueProvider
.public BigQueryIO.Read withoutValidation()
public BigQueryIO.Read withoutResultFlattening()
Only valid when a query is used (fromQuery(java.lang.String)
). Setting this option when reading
from a table will cause an error during validation.
public BigQueryIO.Read usingStandardSql()
Only valid when a query is used (fromQuery(java.lang.String)
). Setting this option when reading
from a table will cause an error during validation.
@Experimental(value=SOURCE_SINK) public BigQueryIO.Read withTemplateCompatibility()
Use new template-compatible source implementation. This implementation is compatible with repeated template invocations. It does not support dynamic work rebalancing.