This page introduces the concept of data migration into a Grakn knowledge base. We currently support migration of CSV, JSON, XML and SQL data. For each type of data, the steps to migrate to GRAKN.AI are:
- define a schema for the data in Graql
- create templated Graql to map the data to the schema
- invoke the Grakn migrator through the shell script or Java API.
If you have not yet set up the Grakn environment, please see the setup guide.
Note: During migration reasoning is switched off. This is to ensure that data will always load consistently regardless of load order
Migration Shell Script
The migration shell script can be found in grakn-dist/bin after it has been unzipped. Usage is specific to the type of migration being performed:
- CSV migration documentation
- JSON migration documentation
- SQL migration documentation
- XML migration documentation
Using Java APIs
Check the Developing With Java section for more details on how to migrate data using java.
Exporting Data from Grakn
It is also possible to export data from Grakn using the migration shell script. Usage is as follows:
usage: graql migrate export -data -schema [-help] [-no] [-batch <arg>] [-uri <arg>] [-keyspace <arg>] -data export data -schema export schema -h,--help print usage message -k,--keyspace <arg> keyspace to use -n,--no dry run- write to standard out -u,--uri <arg> uri to engine endpoint -r, --retry Number of times to retry sending tasks if engine is not available -d,--debug Migration immediatly stops if any transaction fails
Exporting data or the schema from Grakn, into Graql, will always redirect to standard out.
You can find further documentation about the migration language.