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You can select relevés from one or in more databases by defining selection criteria.

Selection criteria can be one or several items from the Header data and/or Species data.

 

Tab sheet Header data

 

First choose (Select item) the header data you want to select. Then press Define range to define a range (e.g. 1930-1950) or Define list to enter a list of data (e.g. 1931, 1935, 1956, …).

You perform the selection by pressing Execute. It is also possible to combine several criteria with Combine criteria with. First choose how to combine the new criterion with the already selected criterion. There are three possibilities.

 

 

Then select an item (Select item) and enter the data at Define range or Define list.

When combining criteria you can also add a selection on species. However, the selection on species always restricts the selection based on the header data.

 

 

Tabsheet Species data

 

The selection on species is executed in the same way as the selection on header data (see above). The items to be chosen (e.g. sociability, fertility, phenology), however, are not present by default. These species attributes can only be entered when they are present in the database. See: Modify database structure.

 

Most common is a selection on species. Two ways of making species lists can be chosen: And/Or and And Not. Choosing And/Or you make a list of which some or all species have to be present in the relevés. You have to define which species always have to be present and the number of the other chosen species that have to be present (Select .. out of ..). Choose And not to make a list of species that should be absent in the relevés. In both lists you can also specify the cover value of the chosen species.

This method to define species enables a selection of clearly delimited vegetation types in your databases.

 

 

General tasks.

 

Execute: Perform the selection.

 

Undo: Delete the latest defined criterion. It depends on the tabblad selected whether the latest criterion of the header data or of the species will be deleted.

 

Save: Save the selection criteria to a file.

 

Retrieve: Retrieve an earlier selection from a file.

 

Embargo filter: Mark this option to exclude relevés, which are embargoed. Both authors and/or projects can be placed under an embargo. See Modify popup lists to change the embargo flag of authors and/or projects.

 

Current selection: Specify what to do with the previous selection. Their relevé numbers are listed in the window at the right part of the screen.

There are three possibilities which resemble Combine criteria with: