title: If two Flyway's are ran at the same time, does it automatically handle this scenario safely?
body: <p>We have multiple products using the same database, each product has its own deployment system which will ultimately trigger off Flyway as part of the procedure to bring the Database up to date.</p>
  
  <p>What if two projects deploy at the same time and run Flyway at exactly the same time? Will Flyway attempt to apply version 1,2,3 twice or will it automatically handle this situation.</p>
  
  <p>This could cause headaches in some scenarios (eg, add 3 rows to a table twice).</p>
  
  <p>Given, this could be rare, but it could happen and I'd like to know if Flyway considers this out of the box?</p>
  
  <p>A solution we discussed in the office would be to acquire a lock on the versioning table. The second instance would have to wait for the lock to be freed before it applied its version(s), forcing it to wait for the previous instance to finish and therefore not applying versions twice.</p>
  
  <p>Thanks,
  Chris</p>
  
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