Nonstop Database, HiRDB Version 9 UAP Development Guide
When two or more tables are manipulated, duplicated data can be eliminated from retrieval results. UNION or DISTINCT specifies duplicated data elimination.
The following figure shows, as an example of eliminating duplicate data, the procedure for retrieving the product codes of products (with at least 10 units ordered) from two order tables and then eliminating the duplicated data.
Figure 2-37 Duplicated data elimination example
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