Hello,
As stated in the documentation I see that:
A deferred transaction starts without a lock and obtains a SHARED
lock on the first read and the first write operation creates a
RESERVED lock.
An immediate acquires a RESERVED lock as soon as the BEGIN command
is executed, without waiting for the database to be used.
An exclusive transaction causes EXCLUSIVE locks to be acquired on
all databases. After a BEGIN EXCLUSIVE, you are guaranteed that no
other thread or process will be able to read or write the database
until the transaction is complete.
Then I see the following statement:
A PENDING lock is always just a temporary stepping stone on the
path to an EXCLUSIVE lock and so the pager module does not track
PENDING locks.
Does that mean that if there are readers accessing the database and I
issue a BEGIN EXCLUSIVE, SQLite will create a PENDING lock barring
new readers to have access? Then as soon as the current readers
finish, the PENDING lock will be upgraded to an EXCLUSIVE lock,
barring other readers and writers from accessing the database, correct?
Thanks,
-- Tito
