Question

How do I avoid read locks in my database?

Answers for multiple databases welcome!

Answer 1

In Oracle the default mode of operation is the Read committed isolation level where a select statement is not blocked by another transaction modifying the data it’s reading. From Data Concurrency and Consistency:

Each query executed by a transaction sees only data that was committed before the query (not the transaction) began. An Oracle query never reads dirty (uncommitted) data.