tFileInputParquet properties for Apache Spark Batch
These properties are used to configure tFileInputParquet running in the Spark Batch Job framework.
The Spark Batch tFileInputParquet component belongs to the File family.
The component in this framework is available in all subscription-based Talend products with Big Data and Talend Data Fabric.
Basic settings
Define a storage configuration component |
Select the configuration component to be used to provide the configuration information for the connection to the target file system such as HDFS. If you leave this check box clear, the target file system is the local system. The configuration component to be used must be present in the same Job. For example, if you have dropped a tHDFSConfiguration component in the Job, you can select it to write the result in a given HDFS system. |
Property type |
Either Built-In or Repository. |
Built-In: No property data stored centrally. |
|
Repository: Select the repository file where the properties are stored. The properties are stored centrally under the Hadoop Cluster node of the Repository tree. The fields that come after are pre-filled in using the fetched data. For further information about the Hadoop Cluster node, see Managing Hadoop connection metadata. |
|
Schema and Edit Schema |
A schema is a row description. It defines the number of fields (columns) to be processed and passed on to the next component. When you create a Spark Job, avoid the reserved word line when naming the fields. Click Edit schema to make changes to the schema. If the current schema is of the Repository type, three options are available:
This component does not support the Object type and the List type. Spark automatically infers data types for the columns in a PARQUET schema. In a Talend Job for Apache Spark, the Date type is inferred and stored as int96. This component offers the advantage of the dynamic schema feature. This allows you to retrieve unknown columns from source files or to copy batches of columns from a source without mapping each column individually. For further information about dynamic schemas, see Dynamic schema. This dynamic schema feature is designed for the purpose of retrieving unknown columns of a table and is recommended to be used for this purpose only; it is not recommended for the use of creating tables. |
Built-In: You create and store the schema locally for this component only. |
|
Repository: You have already created the schema and stored it in the Repository. You can reuse it in various projects and Job designs. |
|
Folder/File |
Browse to, or enter the path pointing to the data to be used in the file system. If the path you set points to a folder, this component will
read all of the files stored in that folder, for example,
/user/talend/in; if sub-folders exist, the sub-folders are automatically
ignored unless you define the property
spark.hadoop.mapreduce.input.fileinputformat.input.dir.recursive to be
true in the Advanced properties table in the
Spark configuration tab.
If you want to specify more than one files or directories in this field, separate each path using a comma (,). The button for browsing does not work with the Spark Local mode; if you are using the other Spark Yarn modes that Talend Studio supports with your distribution, ensure that you have properly configured the connection in a configuration component in the same Job. Use the configuration component depending on the filesystem to be used. |
Advanced settings
Read binary as string |
Select this check box to set spark.sql.parquet.binaryAsString to true, when needed. |
Merge schema |
Select this check box to allow Talend Studio to merge multiple Parquet files with different schemas that can be mutually compatible. For more information, see Schema Merging from the official Spark documentation. |
Read dates in local timezone | Select this check box to use the local timezone of your Spark session. If you leave this check box cleared, the UTC timezone is used. |
Usage
Usage rule |
This component is used as a start component and requires an output link. This component, along with the Spark Batch component Palette it belongs to, appears only when you are creating a Spark Batch Job. Note that in this documentation, unless otherwise explicitly stated, a scenario presents only Standard Jobs, that is to say traditional Talend data integration Jobs. |
Spark Connection |
In the Spark
Configuration tab in the Run
view, define the connection to a given Spark cluster for the whole Job. In
addition, since the Job expects its dependent jar files for execution, you must
specify the directory in the file system to which these jar files are
transferred so that Spark can access these files:
This connection is effective on a per-Job basis. |