org.apache.spark.sql.jdbc

Class PostgresDialect

Object

org.apache.spark.sql.jdbc.PostgresDialect

public class PostgresDialect
extends Object

Constructor Summary

Constructors

Constructor and Description
PostgresDialect()

Method Summary

Modifier and Type	Method and Description
static void	beforeFetch(java.sql.Connection connection, scala.collection.immutable.Map<String,String> properties)
static boolean	canHandle(String url)
static Object	compileValue(Object value)
static scala.Option<DataType>	getCatalystType(int sqlType, String typeName, int size, MetadataBuilder md)
static scala.Option<JdbcType>	getJDBCType(DataType dt)
static String	getSchemaQuery(String table)
static String	getTableExistsQuery(String table)
static String	getTruncateQuery(String table, scala.Option<Object> cascade) The SQL query used to truncate a table.
static scala.Option<Object>	getTruncateQuery$default$2()
static scala.Option<Object>	isCascadingTruncateTable()
static String	quoteIdentifier(String colName)

Methods inherited from class Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PostgresDialect

public PostgresDialect()

Method Detail

canHandle

public static boolean canHandle(String url)

getCatalystType

public static scala.Option<DataType> getCatalystType(int sqlType,
                                                     String typeName,
                                                     int size,
                                                     MetadataBuilder md)

getJDBCType

public static scala.Option<JdbcType> getJDBCType(DataType dt)

getTableExistsQuery

public static String getTableExistsQuery(String table)

isCascadingTruncateTable

public static scala.Option<Object> isCascadingTruncateTable()

getTruncateQuery

public static String getTruncateQuery(String table,
                                      scala.Option<Object> cascade)

The SQL query used to truncate a table. For Postgres, the default behaviour is to also truncate any descendant tables. As this is a (possibly unwanted) side-effect, the Postgres dialect adds 'ONLY' to truncate only the table in question

Parameters:

table - The table to truncate

cascade - Whether or not to cascade the truncation. Default value is the value of isCascadingTruncateTable(). Cascading a truncation will truncate tables with a foreign key relationship to the target table. However, it will not truncate tables with an inheritance relationship to the target table, as the truncate query always includes "ONLY" to prevent this behaviour.

Returns:

The SQL query to use for truncating a table

beforeFetch

public static void beforeFetch(java.sql.Connection connection,
                               scala.collection.immutable.Map<String,String> properties)

quoteIdentifier

public static String quoteIdentifier(String colName)

getSchemaQuery

public static String getSchemaQuery(String table)

compileValue

public static Object compileValue(Object value)

getTruncateQuery$default$2

public static scala.Option<Object> getTruncateQuery$default$2()