A computerized method comprising: determining a read frequency, a write frequency and a data volume for data persistently stored, the data having a first format; selecting a first type of data migration or a second type of data migration, wherein the selecting is derived from at least one of the read frequency, the write frequency and the data volume for the data persistently stored; transforming the data to a second format using the selected type of data migration; and outputting the data for storage in a machine-readable medium, characterized in that upgrading an application from a current version to a new version, wherein the application is to access the data during execution, wherein the transforming of the data to the second format using the selected type of data migration occurs during an uptime of the application; wherein the selecting of the first type of data migration comprises selecting an incremental conversion and wherein transforming the data to the second format comprises transforming the data prior to down time of the application as part of the upgrade of the application from the current version to the new version, wherein the incremental conversion is used to migrate data that has a read frequency above a read threshold but a write frequency below a write threshold, wherein the selecting of the second type of data migration comprises selecting a lazy migration and wherein transforming the data to the second format comprises transforming the data after down time of the application as part of the upgrade of the application from the current version to the new version, wherein the lazy migration is used to migrate data that has a write frequency above the write threshold but a read frequency below the read threshold, and wherein if the data to be migrated has a write frequency above the write threshold and a read frequency above the read threshold, the amount of data volume is used to determine the type of migration, wherein if the data volume is above a volume threshold, any of the incremental conversion and the lazy migration is used and wherein if the data volume is below the volume threshold, down time migration is used. determining a read frequency, a write frequency and a data volume for data persistently stored, the data having a first format; selecting a first type of data migration or a second type of data migration, wherein the selecting is derived from at least one of the read frequency, the write frequency and the data volume for the data persistently stored; transforming the data to a second format using the selected type of data migration; and outputting the data for storage in a machine-readable medium, characterized in that upgrading an application from a current version to a new version, wherein the application is to access the data during execution, wherein the transforming of the data to the second format using the selected type of data migration occurs during an uptime of the application; wherein the selecting of the first type of data migration comprises selecting an incremental conversion and wherein transforming the data to the second format comprises transforming the data prior to down time of the application as part of the upgrade of the application from the current version to the new version, wherein the incremental conversion is used to migrate data that has a read frequency above a read threshold but a write frequency below a write threshold, wherein the selecting of the second type of data migration comprises selecting a lazy migration and wherein transforming the data to the second format comprises transforming the data after down time of the application as part of the upgrade of the application from the current version to the new version, wherein the lazy migration is used to migrate data that has a write frequency above the write threshold but a read frequency below the read threshold, and wherein if the data to be migrated has a write frequency above the write threshold and a read frequency above the read threshold, the amount of data volume is used to determine the type of migration, wherein if the data volume is above a volume threshold, any of the incremental conversion and the lazy migration is used and wherein if the data volume is below the volume threshold, down time migration is used.