Delta concurrency write Issue

User16826994223 — Thu, 17 Jun 2021 07:16:14 GMT

What is concurrent issue in delta, If at a time if we try to write same delta table , it some times fail , how to mitigate that

Re: Delta concurrency write Issue

Ryan_Chynoweth — Thu, 17 Jun 2021 23:57:54 GMT

Delta Lake uses optimistic concurrency control to provide transactional guarantees between writes.

Read: Reads (if needed) the latest available version of the table to identify which files need to be modified (that is, rewritten).
1. Write: Stages all the changes by writing new data files.
2. Validate and commit: Before committing the changes, checks whether the proposed changes conflict with any other changes that may have been concurrently committed since the snapshot that was read. If there are no conflicts, all the staged changes are committed as a new versioned snapshot, and the write operation succeeds. However, if there are conflicts, the write operation fails with a concurrent modification exception rather than corrupting the table as would happen with the write operation on a Parquet table.

Read more about delta lake concurrency here.