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R_M
Hi:

I am new to Oracle and have a probably trivial concurrency question.

How is an ROT implemented ?

Suppose I create an ROT
and then issue the following commands:
select * from table A where colx=3
select * from table A where colx != 3
select * from table B
select * from table A where colx=2
select * from table B

Is the contents of tables A and B saved aside so any concurrent update
transactions succeed ?
Or are tables A and B blocking updates until I close the ROT.

Thanks

Ricardo
Jul 19 '05 #1
1 2294
R_M wrote:
Hi:

I am new to Oracle and have a probably trivial concurrency question.

How is an ROT implemented ?

Suppose I create an ROT
and then issue the following commands:
select * from table A where colx=3
select * from table A where colx != 3
select * from table B
select * from table A where colx=2
select * from table B

Is the contents of tables A and B saved aside so any concurrent update
transactions succeed ?
Kind of.
Changes to the tables are "saved" so you continue to be presented
with data as it existed at the start of your ROT.
Or are tables A and B blocking updates until I close the ROT.


NO blocking occurs.
In Oracle Readers NEVER block writers!

Jul 19 '05 #2

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