I got sequence current value 3
localhost:3401> box.sequence.S:next()
---
- 3
...
I can't find current value in the object
localhost:3401> box.sequence.S
---
- step: 1
id: 1
min: 1
cache: 0
uid: 1
max: 9223372036854775807
cycle: false
name: S
start: 1
...
How to get current value? Didn't find any way in documentation.
As you can see, your sequence S has id=1
There is system space box.space._sequence_data which has current values of all sequences. All you need to do is just select your sequence id from the space: box.space._sequence_data:select(1).
For example, my_seq is 4th sequence in my database.
tarantool> my_seq = box.schema.sequence.create('MySeq', {start=111})
---
...
tarantool> box.space._sequence_data:select(my_seq.id)
---
- []
...
tarantool> my_seq:next()
---
- 111
...
tarantool> box.space._sequence_data:select(my_seq.id)
---
- - [4, 111]
As you can see, right after creation _sequence_data doesn't have any details about new sequence until first use of my_seq:next() which
initialises the sequence.
As you can see box.space._sequence_data:select(my_seq.id) returns tuple with number of the sequence and current value.
Please be aware of absence of guarantees for this method. And there are some issues with replication.
In 2.4.1 sequence:currval() is introduced: https://github.com/tarantool/tarantool/issues/4752