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Database / Mnesia basics Interview questions

How do you change a table's storage type at runtime?

mnesia:change_table_copy_type/3 converts a table's storage type on a given node while the system stays live — for example, promoting a ram_copies table to disc_copies once you decide it needs durability, without dropping and recreating it.

mnesia:change_table_copy_type(person, node(), disc_copies).

This is a schema-level operation, so it's typically run once, deliberately, rather than as part of regular application logic. It doesn't move or duplicate data across nodes by itself — it changes how the copy on the specified node is persisted; adding an entirely new node as a replica is a separate operation handled by mnesia:add_table_copy/3.

What does mnesia:change_table_copy_type/3 let you do?
Is dropping and recreating the table required to change its storage type?

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