kotlin-client/com.couchbase.client.kotlin.query/QueryResult/valueAs

valueAs

inline fun <T> valueAs(name: String = "$", serializer: JsonSerializer? = null): T

Returns a field value from a result with exactly one row. Useful for getting the result of an aggregating function.

Samples

import com.couchbase.client.kotlin.Cluster
import com.couchbase.client.kotlin.query.QueryMetadata
import com.couchbase.client.kotlin.query.QueryResult
import com.couchbase.client.kotlin.query.execute
fun main() { 
   //sampleStart 
   // Single-value query with anonymous result
val count = cluster
    .query("select count(*) from `travel-sample`")
    .execute()
    .valueAs<Long>() // uses default name "$1" 
   //sampleEnd
}
xxxxxxxxxx
 
// Single-value query with anonymous result
val count = cluster
    .query("select count(*) from `travel-sample`")
    .execute()
    .valueAs<Long>() // uses default name "$1" 
Open in Playground →
Target: JVMRunning on v.2.1.10

import com.couchbase.client.kotlin.Cluster
import com.couchbase.client.kotlin.query.QueryMetadata
import com.couchbase.client.kotlin.query.QueryResult
import com.couchbase.client.kotlin.query.execute
fun main() { 
   //sampleStart 
   // Single-value query with named result
val count = cluster
    .query("select count(*) as count from `travel-sample`")
    .execute()
    .valueAs<Long>("count") 
   //sampleEnd
}
xxxxxxxxxx
 
// Single-value query with named result
val count = cluster
    .query("select count(*) as count from `travel-sample`")
    .execute()
    .valueAs<Long>("count") 
Open in Playground →
Target: JVMRunning on v.2.1.10

Parameters

name

the name of the field to extract.

serializer

for converting the field value to the requested type. Defaults to the QueryRow's serializer.

the serializer reads the field value as this type.

Throws

kotlin.IllegalArgumentException

if there is more than one result row

kotlin.NoSuchElementException

if there is no field with the given name