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❖Extract Data Imported to Data Mart

The task type supported by data extraction is data imported to data mart. Data imported to data mart is not actual data query. It neither links to the linked database nor performs actual data query. Instead, it saves the data in the database to a local file and enables the data saved in files to be operational. It mainly works to make the data display and data operations consistent with the results of other data set modules.

The data used in the Materialized Data Set are from the established file, but not read data directly from the database. Therefore, you will be confused and query whether the data in the file can be operated in the same way as if they are in a database. When a data file is read and added to the result of a data set through a special storage technology, the user can perform various operations on the data through Materialize Data Set. At this point, the user feels like operating in a real database, which is the most important function of Materialize Data Set.

After extraction the data, a task will be created in the schedule tasks, which can be run immediately or in customize the time to execute the data set and store the results to the deployed hard disk. A dashboard based on this data set will give preference to the results of Materialize Data Set to display the data. If the actual data in the database changes, a  task for loop execution can be formulated to regularly update the result of Materialized Data Set.

Data imported to data mart can significantly improve the performance of a data set, especially that of a complex data set.

All data sets can be synchronized, except Data Mart Data Set, Embedded Data Mart and Multi-Dimension Data Set can't be synchronized. When the user needs to synchronize the data set data, open the data set and click the "Extract Data" in the metadata area. The interface is shown below:

 

❖One-time Data Extraction

After clicking the "Extract Data" , a dialog box for extracting data pops up, as shown in the following figure:

【Type】The task type supported by data extraction is data imported to data mart.

【Append】It is not checked by default. After checking append, the latest data in the database will be appended to the historical data.

【Update by Column】It is not displayed by default. It is displayed only after append is checked. Only the numeric column and date column can be selected in the update by column.

【Extract Data Regularly】It is not checked.

【Save Settings】After the user sets the configuration information in the Extract Data dialog box, click "Save Settings" to save the relevant configuration on the data set.

【Run】After the user clicks "Run", the data extraction will start once. At this time, the data extraction dialog box disappears, and the data extraction process dialog box will pop up, as shown in the following figure.

The data extraction process dialog box displays the steps of data extraction, including: start, fetch data and generate DataGrid, create data file, store data file in distribution and complete, so that users can know the current data extraction progress. icon is displayed before the completed step, icon is displayed before the step being executed, and the task icon is not displayed before the step to be executed. When the data set is being extracted, an orange icon is displayed before the extract data, and the button for extract data is grayed out. The user clicks "Cancel Data Extract" can stop the extract data. The user clicks the "×" in the upper right corner to close the dialog box, and the background continues to perform the drawing. After the data extraction is successful, a green icon and a release button are displayed next to the extract data; after the data extraction is failed, a red icon is displayed next to the data extraction, and the reason for the data extraction failure is displayed in the red icon. The following figure shows the successful data extraction.

When hovering over the icon, you can view the real-time information of the extracted data, as shown in the following figure:

If the user needs to release the synchronized data set data, he can click "Dispose" to release the synchronized data set data.

 

❖Extract Data Regularly

After clicking "Extract Data", a dialog box for extracting data pops up. Check "Extract Data Regularly" to start timing data synchronization, as shown in the figure below:

【Extract Data Regularly】It is not checked by default. After checking, the user can extract data at a custom time.

【Frequency & Time Condition】It is not displayed by default. It is displayed after the "Extract Data Regularly" is checked. The user can select "Daily, Weekly, and Monthly" to extract data at any time. For the setting method of frequency and time condition, please refer to Schedule Tasks-> Job.

【Schedule Run】After the user clicks the "Schedule Run", the data will be extracted regularly according to the set time.

When the user sets the synchronization time to the current time, the process of extracting data is the same as the one-time data extraction; when the user sets the synchronization time to the future time, a green icon will be displayed beside the extracted data to record the real-time information of the extracted data, as follows the picture shows:

➢Explanation:

1. The user can extract data from a data set as long as he has write permission for the data set.

2. After modifying the configuration information in the Extract Data dialog box, click "Save Settings" to save the configuration information only on the data set, the configuration information will not take effect until you click the "Run" or "Scheduler Run" button.

3. Simultaneously append data into the data mart, the new data of the selected update by column must be greater than the maximum value of the old data of the column can successfully append the new data to the historical data, otherwise the new data will not be added to the historical data.

4. For one-time data extraction, click the "Cancel Data Extract" or "Dispose" button, the icon next to the extract data will disappear; for the scheduled data extraction, only delete the related scheduled task icon will disappear.