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Remove the old query and execute the new script. The output should look like in the following.
More complex predicates can be defined. See Functions and Operators for further information.
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With the SELECT-Operator you choose which events you will see in the output, with the PROJECT you will choose, which attributes should be in the output.
Create a new Odysseus Script file with the PQL template and name it query3.
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out = PROJECT({ATTRIBUTES=['id', 'initialbid', 'seller']},nexmark:auction) |
After translating the following output will be displayed. You can see, that only the selected attributes are printed.
Map
PROJECT only allow the selection of attributes. With the MAP-Operator calculations can be done on the input. The simpliest calculation is the output of an input attribute, so Map is more general than Project. (Warning: You should not use Map instead of Project, because it requires more processing capabilties).