Configuring data mapping to generate a subquery - 7.3

ELT Hive

Version
7.3
Language
English
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Content
Data Governance > Third-party systems > ELT components > ELT Hive components
Data Quality and Preparation > Third-party systems > ELT components > ELT Hive components
Design and Development > Third-party systems > ELT components > ELT Hive components
Last publication date
2024-02-21

Procedure

  1. Click the SubqueryMap component (next to the second tELTOracleInput) to open its Basic settings view.
    Note: Specify the Oracle database connection information in the second ELTMap component in the Job.
  2. Click [...] next to ELT Oracle Map Editor to open its map editor.
  3. Add the input table CourseScore by clicking [+] in the upper left corner of the map editor and then selecting the relevant table name from the drop-down list in the pop-up dialog box.
  4. Add an output table by clicking [+] in the upper right corner of the map editor and then entering the table name TotalScore in the corresponding field in the pop-up dialog box.
  5. Drag StuName, Subject, and Score columns in the input table and then drop them to the output table.
  6. Click the Add filter row button in the upper right corner of the output table and select Add an other(GROUP...) clause from the pop-up menu. Then in the Additional other clauses (GROUP/ORDER BY...) field displayed, enter the clause GROUP BY CourseScore.StuName, CourseScore.Subject.
    Add the aggregate function SUM for the column Score of the output table by changing the expression of this column to SUM(CourseScore.Score).
  7. Click the Generated SQL Select query for 'table1' output tab at the bottom of the map editor to display the corresponding generated SQL statement.
    This SQL query will appear as a subquery in the SQL query generated by the ELTMap component.
  8. Click OK to validate these changes and close the map editor.
  9. Connect the first SubqueryMap to ELTMap using the Link > TotalScore (table1) link. Note that the link is renamed automatically to TotalScore (Table_ref) since the output table TotalScore is a reference table.