# Reading data from databases through context-based dynamic connections

In this scenario, MySQL is used for demonstration purposes. We will read data from database tables with the same data structure but in two different MySQL databases named *project\_q1* and *project\_q2* respectively. We will specify the connections to these databases dynamically at runtime, without making any modification to the Job.

For more technologies supported by Talend, see [Talend components](https://help.qlik.com/talend/r/en-US/7.3/components/defining-context-groups).

### In this section

* [Dropping and linking the components](https://help.qlik.com/talend/en-US/components/7.3/defining-context-groups/dropping-and-linking-components-standard-component-drop)
* [Creating a context variable](https://help.qlik.com/talend/en-US/components/7.3/defining-context-groups/creating-context-variable-standard-component-to-be)
* [Configuring the components](https://help.qlik.com/talend/en-US/components/7.3/defining-context-groups/configuring-components-standard-component)
* [Saving and executing the Job](https://help.qlik.com/talend/en-US/components/7.3/defining-context-groups/saving-and-executing-job-standard-component-press)

**Related information**

[tMysqlConnection](https://help.qlik.com/talend/r/en-US/7.3/components/mysql/tmysqlconnection)

[tMysqlInput](https://help.qlik.com/talend/r/en-US/7.3/components/mysql/tmysqlinput)

[tLogRow](https://help.qlik.com/talend/r/en-US/7.3/components/logs-and-errors/tlogrow)

[tMysqlClose](https://help.qlik.com/talend/r/en-US/7.3/components/mysql/tmysqlclose)