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= Generate a MOLGENIS from existing database =
There is legacy of existing databases, which you may inherit or get your hands on via SQL dumps/TEXT downloads. Below we will first generate a MOLGENIS for an existing database by automatically extracting the MOLGENIS data model from it. Second you will learn how to batch-load existing data sets from delimited text files.

== Generating a MOLGENIS for an existing database ==
 1. Edit the database connection settings in the `molgenis.properties` file to refer to an existing database. See !MolgenisPropertiesFile. In this example it is assumed you connect to the Address Book database from the !AddressBookExample. Alternatively you can download a database dump of your choice or connect to a remote database (assuming proper DatabasePermissions).
 1. Run !handwritten/java/!MolgenisExtractModel.java. The extraction tool will connect to your selected database and extract a model from its table structure. An example output for the Address Book Application



 1. Copy-paste the parts of XML you want to use in your *_db.xml file. Then add a suitable *_ui.xml. Then adapt the `molgenis.properties` file accordingly and generate,compile,run to view the results (as learned in the previous section).

== Batch loading of data ==
MOLGENIS also provides methods to quickly load large data sets from comma or tab separated data files, both in the MolgenisUserInterfaceas well as in the MolgenisJavaApi . This works if:

 * The column headers match the entity `field `definitions as defined in !MolgenisDatabaseXml file(order      doesn’t matter)
 * A special case are !XrefFields that either can use the      xref_field or the xref_label. For example in the case of AddressBookExample ‘contact_id’      and ‘contact_displayname’.

For example: Load data for Contact. Within the MOLGENIS user interface for Contacts choose ‘File’ and then ‘Add in batch’.

In the CSV data dialog paste the following comma seperated values:

{{{
displayname,lastname,firstname,mid_initials,birthday

Prof.dr. R Bischoff,Bischoff,Rainer,,

Dr. R Breitling,Breitling,Rainer,,

Prof.dr. RC Jansen,Ritsert,Jansen,C,
}}}
Load data for Address. In the dialog for Example data for Address again choose ‘File’ and then ‘Add in batch’. Set the ‘address_type’ to ‘work’ as constant for all addresses to be loaded (otherwise you get an error!). Then paste in the CSV data dialog:

{{{
phone,contact_displayname

+31 (0)50 3633338,Prof.dr. R Bischoff

+31 (0)50-3638088,Dr. R Breitling

+31 (0)50-3638089,Prof.dr. RC Jansen
}}}
Notice the cross reference by ‘xref_label’ using ‘contact_displayname’!

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[http://gbic.target.rug.nl/#_ftnref1 "[1]"] These example data was copied from http://www.nbic.nl/nbic/network/?city=Groningen