Data Migration

A few tools are available to assist with migrating data to QuantumLeap.

Migrating from QuantumLeap Crate to Timescale

QuantumLeap provides a self-contained Python script to help with migrating tables from a QuantumLeap CrateDB database to a QuantumLeap Timescale database. The script is located in the timescale-container directory and is called It exports rows in a given Crate table and generates, on stdout, all the SQL statements needed to import that data into Timescale. These include creating a corresponding schema, table and hypertable in PostgreSQL as needed. Note that the script generates DDL statements that, when executed, will result in the exact same table structures the QuantumLeap Timescale back end would have generated on seeing NGSI entities corresponding to the rows stored in the Crate table.

Here's an example usage

$ python --schema mtyoutenant --table etdevice \
    > mtyoutenant.etdevice-import.sql

where we export all the rows in the Crate table mtyoutenant.etdevice. The generated file contains all the SQL statements to recreate the table and insert the data in Timescale. You may want to put this file in the quantumleap-db-setup script's init directory so that data are migrated automatically for you when you bootstrap the QuantumLeap DB on Timescale as explained in the Timescale section.

By default the script exports all the rows in the Crate table, but you can also use the --query argument to specify a query to select only a subset of interest as shown below:

$ python --schema mtyoutenant --table etdevice --query \
    "SELECT * FROM mtyoutenant.etdevice where time_index > '2019-04-15';"