July 31, 2023

tJDBCInput – Docs for ESB Jdbc 7.x

tJDBCInput

Reads any database using a JDBC API connection and extracts fields based on a
query.

tJDBCInput executes a database query
with a strictly defined order which must correspond to the schema definition. Then it
passes on the field list to the next component via a Main row link.

Depending on the Talend
product you are using, this component can be used in one, some or all of the following
Job frameworks:

tJDBCInput Standard properties

These properties are used to configure tJDBCInput running in
the Standard Job framework.

The Standard
tJDBCInput component belongs to the Databases family.

The component in this framework is available in all Talend
products
.

Note: This component is a specific version of a dynamic database
connector. The properties related to database settings vary depending on your database
type selection. For more information about dynamic database connectors, see Dynamic database components.

Basic settings

Database

Select a type of database from the list and click
Apply.

Property Type

Select the way the connection details
will be set.

  • Built-In: The connection details will be set
    locally for this component. You need to specify the values for all
    related connection properties manually.

  • Repository: The connection details stored
    centrally in Repository > Metadata will be reused by this component. You need to click
    the […] button next to it and in the pop-up
    Repository Content dialog box, select the
    connection details to be reused, and all related connection
    properties will be automatically filled in.

This property is not available when other connection component is selected
from the Connection Component drop-down list.

tJDBCInput_1.png

Click this icon to open a database connection wizard and store the
database connection parameters you set in the component Basic
settings
view.

For more information about setting up and storing database
connection parameters, see Talend Studio User Guide.

Connection Component

Select the component that opens the database connection to be reused by this
component.

JDBC URL

The JDBC URL of the database to be used. For
example, the JDBC URL for the Amazon Redshift database is jdbc:redshift://endpoint:port/database.

Drivers

Complete this table to load the driver JARs needed. To do
this, click the [+] button under the table to add
as many rows as needed, each row for a driver JAR, then select the cell and click the
[…] button at the right side of the cell to
open the Module dialog box from which you can select the driver JAR
to be used. For example, the driver jar RedshiftJDBC41-1.1.13.1013.jar for the Redshift database.

For more information, see Importing a database driver.

Driver Class

Enter the class name for the specified driver between double
quotation marks. For example, for the RedshiftJDBC41-1.1.13.1013.jar driver, the name to be entered is
com.amazon.redshift.jdbc41.Driver.

Use Id and Password

The database user authentication data.

To enter the password, click the […] button next to the
password field, and then in the pop-up dialog box enter the password between double quotes
and click OK to save the settings.

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.

  • 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.

Click Edit
schema
to make changes to the schema.

Note: If you
make changes, the schema automatically becomes built-in.
  • View schema: choose this
    option to view the schema only.

  • Change to built-in property:
    choose this option to change the schema to Built-in for local changes.

  • Update repository connection:
    choose this option to change the schema stored in the repository and decide whether
    to propagate the changes to all the Jobs upon completion. If you just want to
    propagate the changes to the current Job, you can select No upon completion and choose this schema metadata
    again in the Repository Content
    window.

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
Talend Studio

User Guide.

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.

Table Name

The name of the table from which data will be retrieved.

Query Type and Query

Specify the database query statement paying particularly attention to the
properly sequence of the fields which must correspond to the schema definition.

  • Built-In: Fill in the query statement in the
    Query field manually or click the
    […] button next to the Query field
    to build the statement graphically using the SQLBuilder.

  • Repository: Select the relevant query stored in the
    Repository by clicking the […] button next to it and in the
    pop-up Repository Content dialog box, select the query to be
    used, and the Query field will be automatically filled
    in.

If using the dynamic schema feature, the SELECT query must
include the * wildcard, to retrieve all of the
columns from the table selected.

Guess Query

Click this button to generate query in the Query field based on
the defined table and schema.

Guess Schema

Click this button to generate schema columns based on the query defined in the
Query field.

Specify a data source alias

Select this check box and in the
Data source alias field displayed, specify the alias of
a data source created on Talend Runtime side to use
the shared connection pool defined in the data source configuration. This option
works only when you deploy and run your Job in Talend Runtime.

This property is not available when other connection component is selected from
the Connection Component drop-down list.

Advanced settings

Use cursor

Select this check box to specify the number of rows you want to work with at
any given time. This option optimises performance.

Trim all the String/Char columns

Select this check box to remove leading whitespace and trailing
whitespace from all String/Char columns.

Check column to trim

Select the check box for corresponding column to remove leading whitespace
and trailing whitespace from it.

This property is not available when the Trim all the String/Char
columns
check box is selected.

Enable Mapping File for
Dynamic

Select this check box to use the specified metadata
mapping file when reading data from a dynamic type column. This check
box is cleared by default.

With this check box selected, you can specify the metadata mapping file
to use by selecting a type of database from the Mapping
File
drop-down list.

For more information about metadata mapping files, see
the section on type conversion of Talend Studio User Guide.

Use PreparedStatement

Select this check box if you want to query the database using a prepared statement. In
the Set PreparedStatement Parameters table displayed, specify the
value for each parameter represented by a question mark ? in the
SQL statement defined in the Query field.

  • Parameter Index: the position of the parameter in the SQL
    statement.

  • Parameter Type: the data type of the parameter.

  • Parameter Value: the value of the parameter.

For a related use case of this property, see Using PreparedStatement objects to query data.

tStatCatcher Statistics

Select this check box to gather the Job processing metadata at the Job level
as well as at each component level.

Global Variables

ERROR_MESSAGE

The error message generated by the component when an error occurs. This is an After
variable and it returns a string.

NB_LINE

The number of rows processed. This is an After variable and it returns an integer.

QUERY

The query statement being processed. This is a Flow variable and it returns a
string.

Usage

Usage rule

This component covers all possible SQL queries for any
database using a JDBC connection.

Dynamic settings

Click the [+] button to add a row in the table
and fill the Code field with a context
variable to choose your database connection dynamically from multiple
connections planned in your Job. This feature is useful when you need to
access database tables having the same data structure but in different
databases, especially when you are working in an environment where you
cannot change your Job settings, for example, when your Job has to be
deployed and executed independent of Talend Studio.

For examples on using dynamic parameters, see Reading data from databases through context-based dynamic connections and Reading data from different MySQL databases using dynamically loaded connection parameters. For more information on Dynamic
settings
and context variables, see Talend Studio
User Guide.

tJDBCInput MapReduce properties (deprecated)

These properties are used to configure tJDBCInput running in the MapReduce Job
framework.

The MapReduce
tJDBCInput component belongs to the MapReduce family.

The component in this framework is available in all subscription-based Talend products with Big Data
and Talend Data Fabric.

The MapReduce framework is deprecated from Talend 7.3 onwards. Use Talend Jobs for Apache Spark to accomplish your integration tasks.

Basic settings

Property type

Either Built-In or Repository.

 

Built-In: No property data stored centrally.

 

Repository: Select the repository file where the
properties are stored.

tJDBCInput_1.png

Click this icon to open a database connection wizard and store the
database connection parameters you set in the component Basic
settings
view.

For more information about setting up and storing database
connection parameters, see Talend Studio User Guide.

JDBC URL

The JDBC URL of the database to be used. For
example, the JDBC URL for the Amazon Redshift database is jdbc:redshift://endpoint:port/database.

Driver JAR

Complete this table to load the driver JARs needed. To do
this, click the [+] button under the table to add
as many rows as needed, each row for a driver JAR, then select the cell and click the
[…] button at the right side of the cell to
open the Module dialog box from which you can select the driver JAR
to be used. For example, the driver jar RedshiftJDBC41-1.1.13.1013.jar for the Redshift database.

For more information, see Importing a database driver.

Class Name

Enter the class name for the specified driver between double
quotation marks. For example, for the RedshiftJDBC41-1.1.13.1013.jar driver, the name to be entered is
com.amazon.redshift.jdbc41.Driver.

Username and Password

The JDBC URL of the database to be used. For
example, the JDBC URL for the Amazon Redshift database is jdbc:redshift://endpoint:port/database.

To enter the password, click the […] button next to the
password field, and then in the pop-up dialog box enter the password between double quotes
and click OK to save the settings.

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.

 

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.

 

Click Edit
schema
to make changes to the schema. If the current schema is of the Repository type, three options are available:

  • View schema: choose this
    option to view the schema only.

  • Change to built-in property:
    choose this option to change the schema to Built-in for local changes.

  • Update repository connection:
    choose this option to change the schema stored in the repository and decide whether
    to propagate the changes to all the Jobs upon completion. If you just want to
    propagate the changes to the current Job, you can select No upon completion and choose this schema metadata
    again in the Repository Content
    window.

Table Name

Type in the name of the table from which you need to read
data.

Die on error

Select the check box to stop the execution of the Job when an error
occurs.

Clear the check box to skip any rows on error and complete the process for
error-free rows. When errors are skipped, you can collect the rows on error using a Row > Reject link.

Query type and
Query

Specify the database query statement paying particularly attention to the
properly sequence of the fields which must correspond to the schema definition.

If using the dynamic schema feature, the SELECT query must
include the * wildcard, to retrieve all of the
columns from the table selected.

Usage

Usage rule

In a
Talend
Map/Reduce Job, it is used as a start component and requires
a transformation component as output link. The other components used along with it must be
Map/Reduce components, too. They generate native Map/Reduce code that can be executed
directly in Hadoop.

For further information about a
Talend
Map/Reduce Job, see the sections
describing how to create, convert and configure a
Talend
Map/Reduce Job of the

Talend Open Studio for Big Data Getting Started Guide
.

Note that in this documentation, unless otherwise
explicitly stated, a scenario presents only Standard Jobs,
that is to say traditional
Talend
data integration Jobs, and non Map/Reduce Jobs.

Hadoop Connection

You need to use the Hadoop Configuration tab in the
Run view to define the connection to a given Hadoop
distribution for the whole Job.

This connection is effective on a per-Job basis.

Limitation

We recommend using the following databases
with the Map/Reduce version of this component: DB2, Informix, MSSQL, MySQL,
Netezza, Oracle, Postgres, Teradata and Vertica.

It may work with other databases as well, but
these may not necessarily have been tested.

Related scenarios

No scenario is available for the Map/Reduce version of this component yet.

tJDBCInput properties for Apache Spark Batch

These properties are used to configure tJDBCInput running in the Spark Batch Job
framework.

The Spark Batch
tJDBCInput component belongs to the Databases family.

This component also allows you to connect and read data from a
RDS MariaDB, a RDS PostgreSQL or a RDS SQLServer database.

The component in this framework is available in all subscription-based Talend products with Big Data
and Talend Data Fabric.

Basic settings

Property type

Either Built-In or Repository.

 

Built-In: No property data stored centrally.

 

Repository: Select the repository file where the
properties are stored.

Use an existing
connection

Select this check box and in the Component List click the relevant connection component to
reuse the connection details you already defined.

JDBC URL

The JDBC URL of the database to be used. For
example, the JDBC URL for the Amazon Redshift database is jdbc:redshift://endpoint:port/database.

If you are using Spark V1.3, this URL should contain the
authentication information, such
as:

Driver JAR

Complete this table to load the driver JARs needed. To do
this, click the [+] button under the table to add
as many rows as needed, each row for a driver JAR, then select the cell and click the
[…] button at the right side of the cell to
open the Module dialog box from which you can select the driver JAR
to be used. For example, the driver jar RedshiftJDBC41-1.1.13.1013.jar for the Redshift database.

For more information, see Importing a database driver.

Class Name

Enter the class name for the specified driver between double
quotation marks. For example, for the RedshiftJDBC41-1.1.13.1013.jar driver, the name to be entered is
com.amazon.redshift.jdbc41.Driver.

Username and Password

Enter the authentication information to the database you need
to connect to.

To enter the password, click the […] button next to the
password field, and then in the pop-up dialog box enter the password between double quotes
and click OK to save the settings.

Available only for Spark V1.4. and onwards.

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.

 

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.

 

Click Edit
schema
to make changes to the schema. If the current schema is of the Repository type, three options are available:

  • View schema: choose this
    option to view the schema only.

  • Change to built-in property:
    choose this option to change the schema to Built-in for local changes.

  • Update repository connection:
    choose this option to change the schema stored in the repository and decide whether
    to propagate the changes to all the Jobs upon completion. If you just want to
    propagate the changes to the current Job, you can select No upon completion and choose this schema metadata
    again in the Repository Content
    window.

Table Name

Type in the name of the table from which you need to read
data.

Query type and
Query

Specify the database query statement paying particularly attention to the
properly sequence of the fields which must correspond to the schema definition.

If you are using Spark V2.0 onwards, the Spark SQL does not
recognize the prefix of a database table anymore. This means that you must enter only
the table name without adding any prefix that indicates for example the schema this
table belongs to.

For example, if you need to perform a query in a table system.mytable, in which the system prefix indicates the schema that the mytable table belongs to, in the query, you must enter mytable only.

Guess Query

Click the Guess Query button to generate the query which
corresponds to your table schema in the Query field.

Guess schema

Click the Guess schema button to retrieve the table
schema.

Advanced settings

Additional JDBC
parameters

Specify additional connection properties for the database connection you are
creating. The properties are separated by semicolon and each property is a key-value
pair, for example, encryption=1;clientname=Talend.

This field is not available if the Use an existing
connection
check box is selected.

Spark SQL JDBC
parameters

Add the JDBC properties supported by Spark SQL to this table.
For a list of the user configurable properties, see JDBC to other database.

This component automatically set the url, dbtable and driver properties by using the configuration from
the Basic settings tab.

Trim all the String/Char
columns

Select this check box to remove leading whitespace and trailing
whitespace from all String/Char columns.

Trim column

This table is filled automatically with the schema being used. Select the check
box(es) corresponding to the column(s) to be trimmed.

Enable partitioning

Select this check box to read data in partitions.

Define, within double quotation marks, the following parameters to
configure the partitioning:

  • Partition column: the numeric
    column used as partition key.

  • Lower bound of the partition
    stride
    and Upper bound of
    the partition stride
    : enter the upper bounds and the
    lower bound to determine the partition stride. These bounds do not
    filter the table rows. All rows in the table are partitioned and
    returned.

  • Number of partitions: the
    number of partitions into which the table rows are split. Each Spark
    worker handles only one of the partitions at a time.

The average size of the partitions is the result of the difference between the
upper bound and the lower bound divided by the number of partitions, that is to say,
(upperBound – lowerBound)/partitionNumber, while the first and the last partitions
also include all the other rows that are not contained in the other partitions.

For example, to partition 1000 rows into 4 partitions, if you enter 0 for
the lower bound and 1000 for the upper bound, each partition will contain 250 rows
and so the partitioning is even. If you enter 250 for the lower bound and 750 for
the upper bound, the second and the third partition will each contain 125 rows and
the first and the last partitions each 375 rows. With this configuration, the
partitioning is skewed.

Usage

Usage rule

This component is used as a start component and requires an output
link..

This component should use a tJDBCConfiguration component present in the same Job to
connect to a database. You need to drop a tJDBCConfiguration component alongside this component and configure the
Basic settings of this component
to use tJDBCConfiguration.

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:

  • Yarn mode (Yarn client or Yarn cluster):

    • When using Google Dataproc, specify a bucket in the
      Google Storage staging bucket
      field in the Spark configuration
      tab.

    • When using HDInsight, specify the blob to be used for Job
      deployment in the Windows Azure Storage
      configuration
      area in the Spark
      configuration
      tab.

    • When using Altus, specify the S3 bucket or the Azure
      Data Lake Storage for Job deployment in the Spark
      configuration
      tab.
    • When using Qubole, add a
      tS3Configuration to your Job to write
      your actual business data in the S3 system with Qubole. Without
      tS3Configuration, this business data is
      written in the Qubole HDFS system and destroyed once you shut
      down your cluster.
    • When using on-premise
      distributions, use the configuration component corresponding
      to the file system your cluster is using. Typically, this
      system is HDFS and so use tHDFSConfiguration.

  • Standalone mode: use the
    configuration component corresponding to the file system your cluster is
    using, such as tHDFSConfiguration or
    tS3Configuration.

    If you are using Databricks without any configuration component present
    in your Job, your business data is written directly in DBFS (Databricks
    Filesystem).

This connection is effective on a per-Job basis.

Related scenarios

For a scenario about how to use the same type of component in a Spark Batch Job, see Writing and reading data from MongoDB using a Spark Batch Job.


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