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In Abiquo 4.2, Abiquo released billing version 4.0.1, compatible with Abiquo 4.x. Added "bill_day_of_month" property to define the periods of billing aggregation on a monthly level.
4.7
The following new usage options were added in Abiquo 4.7
backup_usage with backup_policy_X and the backup_policy_X_code
5.0.1
Do not store rows with 0 values to optimize space.
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See Create custom billing usage queries with SQL
5.1
The following new usage options were added in Abiquo 5.1
Fee per VM:
vm_usage
vm_on_usage
vm_off_usage