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Sequences
- Thread starter engdict
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flstffatboy
Technical User
- Sep 19, 2002
- 84
engdict,
The value of 20 refers to the amount of sequence numbers held in the cache.
If you create a sequence with cache 20 the instance will "buffer" the first 20 numbers in memory. If you shutdown the instance and bring it back on line, whether you've actually used those cached sequence numbers or not, the instance will cache another 20 sequence numbers starting at 21. So unless otherwise coded, you stand a chance of having gaps in you sequence generation.
flstffatboy
The value of 20 refers to the amount of sequence numbers held in the cache.
If you create a sequence with cache 20 the instance will "buffer" the first 20 numbers in memory. If you shutdown the instance and bring it back on line, whether you've actually used those cached sequence numbers or not, the instance will cache another 20 sequence numbers starting at 21. So unless otherwise coded, you stand a chance of having gaps in you sequence generation.
flstffatboy
flstffatboy,
You ALWAYS run the risk of gaps in sequences (hundreds of reasons why). Sequences provide an integer that is (a) UNIQUE (b) INCREASING (mathematicians call this monotonically increasing). There is a long thread about this on asktom.oracle.com DaPi - no silver bullet
You ALWAYS run the risk of gaps in sequences (hundreds of reasons why). Sequences provide an integer that is (a) UNIQUE (b) INCREASING (mathematicians call this monotonically increasing). There is a long thread about this on asktom.oracle.com DaPi - no silver bullet
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