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Write-through cache

How does write-through cache ensure “complete data consistency”?
If you first write data to the cache (I am assuming that the focus is mostly here is on distributed cache) and then to the database, in the case that your application process crashes after you made a write into the cache, your source of truth datastore is not updated.
The subsequent read requests will be served from the cache. Then, eventually, such record gets evicted and since the database hasn’t persisted the record, read requests after eviction will be returning different values.
This statement in the course is very misleading. Please clarify.