dataframe-jdbc/org.jetbrains.kotlinx.dataframe.io.db

Package-level declarations

Types

abstract class AdvancedDbType(dbTypeInJdbcUrl: String) : DbType

Alternative version of DbType that allows you to customize type mapping by initializing a JdbcToDataFrameConverter instance for each JDBC type.

AnyJdbcToDataFrameConverter

typealias AnyJdbcToDataFrameConverter = JdbcToDataFrameConverter<*, *, *>

DbColumnBuilder

fun interface DbColumnBuilder<in D, out P>

DbResultSetReader

fun interface DbResultSetReader<out J>

DbType

abstract class DbType(val dbTypeInJdbcUrl: String)

The DbType class represents a database type used for reading a dataframe from the database.

DbValuePreprocessor

fun interface DbValuePreprocessor<in J, out D>

This preprocessor can be created for types where you want to convert the values coming from ResultSet.getObject to a different type more suitable to be put in a DataColumn

DuckDb

object DuckDb : AdvancedDbType

Represents the DuckDB database type.

open class H2(val mode: H2.Mode = Mode.Regular) : DbType

Represents the H2 database type.

JdbcToDataFrameConverter

class JdbcToDataFrameConverter<J, D, P>(val expectedJdbcType: KType, val resultSetReader: DbResultSetReader<J>?, val preprocessedValueType: KType, val valuePreprocessor: DbValuePreprocessor<J, D>?, val targetSchema: ColumnSchema?, val columnBuilder: DbColumnBuilder<D, P>?)

Represents all type information that can be retrieved from an SQL column. This can be extended for your specific DbType if you need extra information.

MariaDb

object MariaDb : DbType

Represents the MariaDb database type.

MsSql

object MsSql : DbType

Represents the MSSQL database type.

MySql

object MySql : DbType

Represents the MySql database type.

PostgreSql

object PostgreSql : DbType

Represents the PostgreSql database type.

Sqlite

class Sqlite(val customTypesMap: Map<String, SqliteCustomTypeConverter<*, *>> = emptyMap(), val customColumnsMap: Map<String, SqliteCustomTypeConverter<*, *>> = emptyMap()) : AdvancedDbType

Represents the Sqlite database type.

SqliteCustomConvertersBuilder

class SqliteCustomConvertersBuilder @PublishedApi constructor

DSL builder collected by Sqlite.withCustomConverters. Register converters via forType (matches by declared SQL type name) or forColumn (matches by column name; takes precedence over forType).

SqliteCustomTypeConverter

data class SqliteCustomTypeConverter<T, R>(val expectedType: KType, val resultingType: KType, val convert: (rawValue: T) -> R)

A user-provided converter from an SQLite declared column type name to the DataFrame column type and a lambda that converts each stored value.

TableColumnMetadata

class TableColumnMetadata(val name: String, val sqlTypeName: String, val jdbcType: Int, val size: Int, val javaClassName: String, val isNullable: Boolean = false)

Represents a column in a database table to keep all required meta-information.

TableMetadata

class TableMetadata(val name: String, val schemaName: String?, val catalogue: String?)

Represents a table metadata to store information about a database table, including its name, schema name, and catalogue name.

Properties

isMultiBit

internal val TableColumnMetadata.isMultiBit: Boolean

true for a multi-bit BIT(M) column, M > 1, in MySQL and MariaDB.

UNNAMED_COLUMN_PREFIX

internal const val UNNAMED_COLUMN_PREFIX: String

Functions

cast

fun <D, P> DbColumnBuilder<*, *>.cast(): DbColumnBuilder<D, P>

fun <J, D> DbValuePreprocessor<*, *>.cast(): DbValuePreprocessor<J, D>

fun <J, D, P> JdbcToDataFrameConverter<*, *, *>.cast(): JdbcToDataFrameConverter<J, D, P>

castToAny

fun DbColumnBuilder<*, *>.castToAny(): DbColumnBuilder<Any?, Any?>

fun DbValuePreprocessor<*, *>.castToAny(): DbValuePreprocessor<Any?, Any?>

fun JdbcToDataFrameConverter<*, *, *>.castToAny(): JdbcToDataFrameConverter<Any?, Any?, Any?>

driverClassNameFromUrl

fun driverClassNameFromUrl(url: String): String

Retrieves the driver class name from the given JDBC URL.

extractDBTypeFromConnection

fun extractDBTypeFromConnection(connection: Connection): DbType

Extracts the database type from the given connection. For H2, fetches the actual MODE from the active connection settings. For other databases, extracts type from URL.

extractDBTypeFromUrl

fun extractDBTypeFromUrl(url: String?): DbType

Extracts the database type from the given JDBC URL.

jdbcToDfConverterFor

inline fun <reified J> jdbcToDfConverterFor(isNullable: Boolean = typeOf<J>().isMarkedNullable): JdbcToDataFrameConverter<J?, J?, J?>

fun <J> jdbcToDfConverterFor(jdbcSourceType: KType): JdbcToDataFrameConverter<J?, J?, J?>

withColumnBuilder

fun <J, D, P> JdbcToDataFrameConverter<J, D, *>.withColumnBuilder(targetSchema: ColumnSchema?, canIntroduceNulls: Boolean = false, columnBuilder: DbColumnBuilder<D, P>?): JdbcToDataFrameConverter<J, D, P>

withPreprocessor

inline fun <J, reified D> JdbcToDataFrameConverter<J, *, *>.withPreprocessor(canIntroduceNulls: Boolean = false, valuePreprocessor: DbValuePreprocessor<J, D>?): JdbcToDataFrameConverter<J, D, D>

fun <J, D> JdbcToDataFrameConverter<J, *, *>.withPreprocessor(preprocessedValueType: KType, canIntroduceNulls: Boolean = false, valuePreprocessor: DbValuePreprocessor<J, D>?): JdbcToDataFrameConverter<J, D, D>

withResultReader

fun <J, D, P> JdbcToDataFrameConverter<J, D, P>.withResultReader(resultSetReader: DbResultSetReader<J>?): JdbcToDataFrameConverter<J, D, P>

withTargetSchema

fun <J, D, P> JdbcToDataFrameConverter<J, D, P>.withTargetSchema(targetSchema: ColumnSchema?): JdbcToDataFrameConverter<J, D, P>