tMySQLInvalidRows

Checks MySQL database rows against specific Data Quality patterns (regular
expression) or Data Quality rules (business rule).

tMySQLInvalidRows extracts DB rows that do not match a given data quality
pattern or rule. You can then implement any required correction.

tMySQLInvalidRows Standard properties

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

The Standard
tMySQLInvalidRows component belongs to the Data Quality and the Databases families.

This component is available in Talend Data Management Platform, Talend Big Data Platform, Talend Real Time Big Data Platform, Talend Data Services Platform, Talend MDM Platform and Talend Data Fabric.

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.
Validation type	Either Regex pattern validation or DQ rule validation.
	Regex pattern validation: Validate data in the database against regex patterns.
	DQ rule validation: Validate data in the database against DQ rules.
Property type	Either Built-in or Repository.
	Built-in: No property data stored centrally.
	Repository: Select the repository file where Properties are stored. The fields that come after are pre-filled in using the fetched data.
DB Version	Select the MySQL version you are using.
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: 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. 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	Database server IP address.
Port	Listening port number of DB server.
Database	Name of the database.
Username and Password	DB 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 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 and thus reuse it when needed. Related topic: see Talend Studio User Guide.
Table Name	Enter the name of the table to be read.
Where clause	Enter a WHERE clause to define a row filter on the table. You can use the WHERE clause to filter the rows you want to analyze in the table. This WHERE clause enables you then to retrieve valid and invalid data that match certain specified criteria or conditions.

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.
Enable stream	Select this check box to enables streaming over buffering. This allows reading from large tables without consuming large amount of memory in order to optimize the performance.
Trim all the String/Char columns	Select this check box to remove leading and trailing whitespace from all the String/Char columns.
Trim column	Select this check box to remove leading and trailing whitespace from the defined columns. This check box is not visible if Trim all the String/Char columns is selected. Clear Trim all the String/Char columns to enable Trim column.
tStatCatcher Statistics	Select this check box to collect log data at the component level.

Global Variables

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. QUERY: the query statement being processed. This is a Flow variable and it returns a string. 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. A Flow variable functions during the execution of a component while an After variable functions after the execution of the component. 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.

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.

QUERY: the query statement being processed. This is a Flow
variable and it returns a string.

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.

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

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.

Usage

Usage rule	This component can be used as a start or intermediary step. It requires an output flow.
Note: Available only for Regex pattern validation.	Analyzed column
Note: Available only for Regex pattern validation.	Custom pattern
Note: Available only for Regex pattern validation.	Patterns list
Note: Available only for DQ rule validation.	DQ rule list
Note: Available only for DQ rule validation.	Query type


Note: Available only for DQ rule validation.	Guess Query
Note: Available only for DQ rule validation.	Guess schema
Note: Available only for DQ rule validation.	Query
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 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.

Reading email addresses from a DB table and retrieving specific
data

This scenario applies only to Talend Data Management Platform, Talend Big Data Platform, Talend Real Time Big Data Platform, Talend Data Services Platform, Talend MDM Platform and Talend Data Fabric.

This scenario is a two-component Job created in
Talend Studio
. In this Job, tMySQLInvalidRows reads the email
addresses for people from a specific country from a MySQL database table, filters data
using a WHERE clause to narrow down the validation process, checks the email values against
the given
Talend Studio
email pattern and finally extracts filtered data including the invalid rows and
displays them on the console.

Below is the database table used in this example, some customers are from
the USA and others are from Canada. The Email column contains some
invalid addresses. The tMySQLInvalidRows component
filters data in the Email column to read only the emails for the
customers from the USA, and then validates these email addresses against the EmailAddress pattern.

In this scenario, we have already stored the schemas of the input table in
the Repository. For more information about storing schema metadata in the Repository tree view, see
Talend Studio User Guide.

Setting up your Job

In the Repository tree view, expand in
succession the Metadata and the DB Connections nodes where you have stored the input
schemas and drop the relevant connection onto the design workspace.

The Components dialog box displays.
Select tMySQLInvalidRows from the list and
click OK to close the dialog box.

The tMySQLInvalidRows component displays on
the workspace. The MySQL table used in this scenario is called
customers. It holds the customers’
customer_id, account_num, Iname, fname, country and
Email columns.
Drop tLogRow from the Palette onto the design workspace.
Connect the two components together using the Main link.

Setting up the schema

Double-click tMySQLInvalidRows to display its
Basic settings view and define its
properties.

All database connection fields are automatically filled in. If you do not
define your input files in the Repository, fill in the details manually after
selecting Built-in in the Property Type field
From the Validation type list, select
Regex pattern validation.

This will validate data in the selected rows against a regex pattern. For an
example scenario about validating data against DQ rule, see Checking customer table against a given DQ rule to select customer records.
In the Table Name field, type in the name of
the database table on which you want to run the Job,
customer1 in this example.
In the Where clause field, type in the WHERE
clause that will restrict the number of the analyzed rows.

In this example you want to examine only the emails of the customers from the
USA.
In the Analyzed column list, select the
column you want to analyze, Email in this example.
In the Patterns list, select the
Talend Studio
database pattern against which you want to
check addresses from the Email column, Email
Address in this example.

If you select the Custom pattern check box,
you can customize the regular expression against which the data is to be
checked.
Double click tLogRow to open its Basic settings view and define its properties as
needed.

Executing the Job

Save your Job.
Press F6 to execute it.

The tMySQLInvalidRows component analyzed the
email addresses only for customers from the USA in the database table against
the selected SQL pattern (Email Address), and then it
extracted all filtered data including the invalid email addresses.

Checking customer table against a given DQ rule to select customer
records

This scenario applies only to Talend Data Management Platform, Talend Big Data Platform, Talend Real Time Big Data Platform, Talend Data Services Platform, Talend MDM Platform and Talend Data Fabric.

This scenario is a three-component Job that checks a MySQL customer table
against a given data quality rule so as to query specific customer records.

These components used in the Job are:

tMysqlConnection: this component creates the
connection to the MySQL database of interest so that the other components can reuse
it.
tMySQLInvalidRows: this component reuses the
connection created by tMysqlConnection and query the
customer records of interest against the given data quality rule.
tLogRow: this component presents the result of
running this Job.

To replicate this scenario, proceed as illustrated in the following
sections:

Dropping and linking the components

From the Palette, drop tMysqlConnection, tMySQLInvalidRows and tLogRow onto the design workspace.

You can label any component in the workspace the way you need. For further
information about how to label a component, see
Talend Studio User Guide.
Right-click tMysqlConnection and select
the Trigger > OnSubjobOk link to connect this component to tMySQLInvalidRows.
Repeat this operation but select the Row
> Main link to connect tMySQLInvalidRows to tLogRow.

Configuring the connection to the database

To configure the connection to the MySQL database of interest, proceed as
follows:

Double-click tMysqlConnection to open its
Component view.
In the DB version field, select the
version of your MySQL database. It is Mysql
5 in this example.
In the Host field, type in the server IP
address of the database to which you want to connect, localhost in this example.
In the Port field, type in the port
number of the database to which you want to connect, 3306 in this example.
In the Database field, enter the name of
the database in which you need to check the customer table, crm in this example.
In the Username and the Password fields, enter the authentication
information to connect to the database of interest.

Configuring the query of the customer records of interest

Double-click tMySQLInvalidRows to open
its Component view.
In the Validation type field, select
DQ rule validation in order to use the
given data quality rule.
Select Use an existing connection to
reuse the connection that tMysqlConnection
creates.
Click the […] button next to Edit schema to open the schema editor.
Click the [+] button three times to add
throw rows and rename them as Name,
DOB and Email, respectively.
In the DOB row, select VARCHAR in the DB
type column, enter 19 in
the Length column and 0 in the Precision column.
Click OK to validate these changes and
accept the propagation prompted by the pop-up dialog box.
In the Table name field, enter or browse
to the database table to be checked, cust
in this example.
In the Where clause field, type in the
where clause to be used, in addition to the given data quality rule, to
query the customer data of interest. In this scenario, enter
cust.Email like 's%' within the quotation marks to
retrieve the email records beginning with the letter s or S.
In the DQ rule list field, select the
data quality rule to be used. In this scenario, select cust_age. This rule is a demo rule reading
18<=((TO_DAYS(NOW())-TO_DAYS(DOB))/365)

You can check the available data quality rules in Libraries > Rules > SQL of the DQ
Repository. The cust_age
rule can be imported from the TDQEEDEMOJAVA project.

For further information about the DQ
Repository and its items and about how to import the data
quality demo project, see the
Talend Studio
User Guide
Click Guess Query to generate the
corresponding query clause that uses the Not clause.

In the Query field, change 18 to 20 to
modify the clause as the following:


"SELECT `Name`, `DOB`, `Email` FROM `crm`.`cust`
  WHERE (NOT ( 20&gt;((TO_DAYS(NOW())-TO_DAYS(DOB))/365) )
  AND `cust`.`Email` like 's%')"

"SELECT `Name`, `DOB`, `Email` FROM `crm`.`cust`

WHERE (NOT ( 20>((TO_DAYS(NOW())-TO_DAYS(DOB))/365) )

AND `cust`.`Email` like 's%')"

This clause allows you to select the customers whose ages count 20 or more.

Executing the Job

The tLogRow component presents the execution
result of the Job. You can configure the presentation mode on its Component view.

To do this, double-click tLogRow to open the
Component view and in the Mode area, select the Table (print values in
cells of a table) option.

To execute this Job, press F6.

Once done, the Run view is opened automatically,
where you can check the execution result.

You can read that the customer records beginning with the letter S are retrieved
and their ages are all more than 20.

Document get from Talend https://help.talend.com

Thank you for watching.

Docs 7.x

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tMySQLInvalidRows – Docs for ESB 7.x

tMySQLInvalidRows