SQLite multi process access

Question

We are using SQLite in a multi processes and multi threaded application. The SQLite database files are encrypted using the embedded SQLite encryption. The FAQ states that SQLite

Answer 1

Thanks for all your comments!

(it is to mention we are using the System.Data.SQLite .Net library)

In the meanwhile we made some more tests and here are the outcomes

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We've built a tester that does the following: - create a table with a number of fields. One of the fields - nvarchar(255) - has a unique index: "create unique index IX_MyKey on Table (MyKey)" - start many idenctical processes (25) simultaneously - Each process has a Key (string representing a number 1-25) - Each process has a single (main) thread doing the following in a loop for 30 sec:

read the record where MyKey=@MyKey (the Key of the process) get a value of a numeric field write back 'value + 1' to the same field of the same record "insert or replace ... where MyKey=@MyKey"

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• When we do all above using the System.Data.SQLite library without encryption - everything works as expected (including locks that are slowing down the access to the database when the amount of processes increases)

• When we use encryption (by setting a password to the database), the index unique constrain is "broken" - there appear records having the same MyKey value

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So it seams the problem is somehow related to encryption...