H2

Kotlin DataFrame supports reading from an H2 database using JDBC.

Requires the dataframe-jdbc module, which is included by default in the general dataframe artifact and in %use dataframe for Kotlin Notebook.

You’ll also need the official H2 JDBC driver:

dependencies {
    implementation("com.h2database:h2:$version")
}

USE {
    dependencies("com.h2database:h2:$version")
}

The actual Maven Central driver version could be found here.

Read

DataFrame can be loaded from a database in several ways:
a user can read data from a SQL table by given name (readSqlTable),
as a result of a user-defined SQL query (readSqlQuery),
or from a given ResultSet (readResultSet).
It is also possible to load all data from non-system tables, each into a separate DataFrame (readAllSqlTables).

See Read from SQL databases for more details.

import org.jetbrains.kotlinx.dataframe.io.DbConnectionConfig
import org.jetbrains.kotlinx.dataframe.api.*

val url = "jdbc:h2:mem:testDatabase"
val username = "sa"
val password = ""

val dbConfig = DbConnectionConfig(url, username, password)

val tableName = "Customer"

val df = DataFrame.readSqlTable(dbConfig, tableName)

22 August 2025