Working with Sequence
Last modified: 03 March 2025A sequence is a database object that automatically generates integer values in sequential order. It is particularly useful in generating unique identifiers and primary keys.
Define a sequence
To define a sequence in Exposed, use the Sequence class:
val myseq = Sequence("my_sequence") // my_sequence is the sequence name.Several parameters can be specified to control the properties of the sequence:
private val myseq = Sequence(
name = "my_sequence",
startWith = 4,
incrementBy = 2,
minValue = 1,
maxValue = 10,
cycle = true,
cache = 20
)Create a sequence
To create a sequence, use the .createSequence() method provided by SchemaUtils:
SchemaUtils.createSequence(myseq)Drop a sequence
To drop a sequence, use the .dropSequence() method provided by SchemaUtils:
SchemaUtils.dropSequence(myseq)Access the next value
You can access the next value in a sequence by using the .nextIntVal() function:
val nextVal = myseq.nextIntVal()
val id = StarWarsFilms.insertAndGetId {
it[id] = nextVal
it[name] = "The Last Jedi"
it[sequelId] = 8
it[director] = "Rian Johnson"
}val firstValue = StarWarsFilms.select(nextVal).single()[nextVal]