I dont know how to store and get back the data. is there any db in daml ?
Daml is a language that is designed around a distributed ledger. In a sense, the only useful thing you can do with it is precisely persisting data on a database. Rather than using the approach of explicitly interacting with the ledger, though, in Daml all your interactions with contracts are persistent. When you create a contract, the contract is already persisted. When you exercise a choice, the execution of that is tracked on the ledger and new contracts originating from that choice are a well. You can then read data either by interacting with active contracts from within Daml or by using the Ledger API to have an external application read data from the ledger, be it contracts or transactions.
The idea of creating, updating and deleting records can be implemented in practical terms, but your approach will go less directly towards that direction. In Daml, you usually design contracts that interact with each other and form a workflow. The set of active contracts result from that workflow can be interacted with, either from within the language or via the Ledger API.
If you haven’t already, going through our introduction to Daml in the documentation is probably the best way to get started modeling your workflows.
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