tMemSQLOutput properties - 6.3

Talend Open Studio for Big Data Components Reference Guide

EnrichVersion
6.3
EnrichProdName
Talend Open Studio for Big Data
task
Data Governance
Data Quality and Preparation
Design and Development
EnrichPlatform
Talend Studio

Component family

Big Data/MemSQL

 

Basic settings

Property type

Either Built-in or Repository.

 

 

Built-in: No property data stored centrally.

 

 

Repository: Select the repository file in which the properties are stored. The fields that follow are completed automatically using the data retrieved.

 

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.

Note

When a Job contains the parent Job and the child Job, if you need to share an existing connection between the two levels, for example, to share the connection created by the parent Job with the child Job, you have to:

  1. In the parent level, register the database connection to be shared in the Basic settings view of the connection component which creates that very database connection.

  2. In the child level, use a dedicated connection component to read that registered database connection.

For an example about how to share a database connection across Job levels, see Talend Studio User Guide.

 

Host

Enter the location of the server of the MemSQL database to be used.

 

Port

Enter the listening port number of the database server.

 

Database

Enter the name of the MemSQL database to be used.

 

Username and Password

Enter the user authentication data for connecting to the database to be used.

 

Table

Enter the name of the table to be written. Note that only one table can be written at a time

 

Action on table

On the table defined, you can perform one of the following operations:

None: No operation is carried out.

Drop and create a table: The table is removed and created again.

Create a table: The table does not exist and gets created.

Create a table if not exists: The table is created if it does not exist.

Drop a table if exists and create: The table is removed if it already exists and created again.

Clear a table: The table content is deleted.

 

Action on data

On the data of the table defined, you can perform:

Insert: Add new entries to the table. If duplicates are found, the job stops.

Update: Make changes to existing entries.

Insert or update: Insert a new record. If the record with the given reference already exists, an update would be made.

Update or insert: Update the record with the given reference. If the record does not exist, a new record would be inserted.

Delete: Remove entries corresponding to the input flow.

Warning

You must specify at least one column as a primary key on which the Update and Delete operations are based. You can do that by clicking Edit Schema and selecting the check box(es) next to the column(s) you want to set as primary key(s). For an advanced use, click the Advanced settings view where you can simultaneously define primary keys for the update and delete operations. To do that: Select the Use field options check box and then in the Key in update column, select the check boxes next to the column name on which you want to base the update operation. Do the same in the Key in delete column for the deletion operation.

 

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. The schema is either Built-In or stored remotely in the Repository.

 

 

Built-In: You create and store the schema locally for this component only. Related topic: see Talend Studio User Guide.

 

 

Repository: You have already created the schema and stored it in the Repository. You can reuse it in various projects and Job designs. Related topic: see Talend Studio User Guide.

When the schema to be reused has default values that are integers or functions, ensure that these default values are not enclosed within quotation marks. If they are, you must remove the quotation marks manually.

For more details, see the article Verifying default values in a retrieved schema on Talend Help Center (https://help.talend.com).

  

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.

 

Die on error

This check box is clear by default.This allows you to skip the row in error and complete the process for error-free rows.

Advanced settings

Additional JDBC parameters

Specify additional connection properties for the DB connection you are creating. This option is not available if you have selected the Use an existing connection check box in the Basic settings.

Note

You can press Ctrl+Space to access a list of predefined global variables.

 

Use batch size

Select this check box to activate the batch mode for data processing. In the Batch Size field that appears when this check box is selected, you can type in the number you need to define the batch size to be processed.

 

Additional Columns

This option is not available if you have just created the database table (even if you delete it beforehand). This option allows you to call SQL functions to perform actions on columns, provided that these are not insert, update or delete actions, or actions that require pre-processing.

 

 

Name: Type in the name of the schema column to be altered or inserted.

 

 

SQL expression: Type in the SQL statement to be executed in order to alter or insert the data in the corrsponding column.

 

 

Position: Select Before, Replace or After, depending on the action to be performed on the reference column.

 

 

Reference column: Type in a reference column that tMemSQLOutput can use to locate or replace the new column, or the column to be modified.

 

Use field options

Select this check box to customize a request, particularly if multiple actions are being carried out on the data.

 

Enable debug mode

Select this check box to display each step involved in the process of writing data in the database.

 

tStatCatcher Statistics

Select this check box to collect log data at the component level.

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.

The Dynamic settings table is available only when the Use an existing connection check box is selected in the Basic settings view. Once a dynamic parameter is defined, the Component List box in the Basic settings view becomes unusable.

For examples on using dynamic parameters, see Scenario 3: Reading data from MySQL databases through context-based dynamic connections and Scenario: 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.

Global Variables

NB_LINE: the number of rows read by an input component or transferred to an output component. This is an After variable and it returns an integer.

NB_LINE_UPDATED: the number of rows updated. This is an After variable and it returns an integer.

NB_LINE_INSERTED: the number of rows inserted. This is an After variable and it returns an integer.

NB_LINE_DELETED: the number of rows deleted. This is an After variable and it returns an integer.

NB_LINE_REJECTED: the number of rows rejected. This is an After variable and it returns an integer.

ERROR_MESSAGE: the error message generated by the component when an error occurs. This is an After variable and it returns a string. This variable functions only if the Die on error check box is cleared, if the component has this check box.

To fill up a field or expression with a variable, press Ctrl + Space to access the variable list and choose the variable to use from it.

For further information about variables, see Talend Studio User Guide.

A Flow variable functions during the execution of a component while an After variable functions after the execution of the component.

Usage

This component must be used as an output component. It allows you to carry out actions on a table or on the data of a table in a MemSQL database.

Log4j

If you are using a subscription-based version of the Studio, the activity of this component can be logged using the log4j feature. For more information on this feature, see Talend Studio User Guide.

For more information on the log4j logging levels, see the Apache documentation at http://logging.apache.org/log4j/1.2/apidocs/org/apache/log4j/Level.html.

Limitation

Due to license incompatibility, one or more JARs required to use this component are not provided. You can install the missing JARs for this particular component by clicking the Install button on the Component tab view. You can also find out and add all missing JARs easily on the Modules tab in the Integration perspective of your studio. For details, see the article Installing External Modules on Talend Help Center (https://help.talend.com) how to configure the Studio in the Talend Installation and Upgrade Guide.