Package org.apache.flink.cdc.connectors.db2.source.dialect

Class Db2ChunkSplitter

java.lang.Object

org.apache.flink.cdc.connectors.base.source.assigner.splitter.JdbcSourceChunkSplitter

org.apache.flink.cdc.connectors.db2.source.dialect.Db2ChunkSplitter

All Implemented Interfaces:

ChunkSplitter

@Internal
public class Db2ChunkSplitter
extends JdbcSourceChunkSplitter

The splitter to split the table into chunks using primary-key (by default) or a given split key.

Field Summary

Fields inherited from class org.apache.flink.cdc.connectors.base.source.assigner.splitter.JdbcSourceChunkSplitter

dialect, sourceConfig

Constructor Summary

Constructors

Constructor	Description
Db2ChunkSplitter(JdbcSourceConfig sourceConfig, JdbcDataSourceDialect dialect, ChunkSplitterState chunkSplitterState)

Method Summary

Modifier and Type	Method	Description
protected org.apache.flink.table.types.DataType	fromDbzColumn(io.debezium.relational.Column splitColumn)	Get a corresponding Flink data type from a debezium Column.
protected Long	queryApproximateRowCnt(io.debezium.jdbc.JdbcConnection jdbc, io.debezium.relational.TableId tableId)	Approximate total number of entries in the lookup table.
protected Object	queryNextChunkMax(io.debezium.jdbc.JdbcConnection jdbc, io.debezium.relational.TableId tableId, io.debezium.relational.Column column, int chunkSize, Object includedLowerBound)	Query the maximum value of the next chunk, and the next chunk must be greater than or equal to includedLowerBound value [min_1, max_1), [min_2, max_2),...

Methods inherited from class org.apache.flink.cdc.connectors.base.source.assigner.splitter.JdbcSourceChunkSplitter

calculateDistributionFactor, close, generateSplits, getCurrentSplittingTableId, getSplitColumn, hasNextChunk, isChunkEndGeMax, isChunkEndLeMax, isEvenlySplitColumn, open, queryMin, queryMinMax, snapshotState

Methods inherited from class java.lang.Object

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

Constructor Detail

Db2ChunkSplitter

public Db2ChunkSplitter(JdbcSourceConfig sourceConfig,
                        JdbcDataSourceDialect dialect,
                        ChunkSplitterState chunkSplitterState)

Method Detail

fromDbzColumn

protected org.apache.flink.table.types.DataType fromDbzColumn(io.debezium.relational.Column splitColumn)

Description copied from class: JdbcSourceChunkSplitter

Get a corresponding Flink data type from a debezium Column.

Specified by:

fromDbzColumn in class JdbcSourceChunkSplitter

Parameters:

splitColumn - dbz split column.

Returns:

flink data type

queryNextChunkMax

protected Object queryNextChunkMax(io.debezium.jdbc.JdbcConnection jdbc,
                                   io.debezium.relational.TableId tableId,
                                   io.debezium.relational.Column column,
                                   int chunkSize,
                                   Object includedLowerBound)
                            throws SQLException

Description copied from class: JdbcSourceChunkSplitter

Query the maximum value of the next chunk, and the next chunk must be greater than or equal to includedLowerBound value [min_1, max_1), [min_2, max_2),... [min_n, null). Each time this method is called it will return max1, max2...

Each database has different grammar to get limit number of data, for example, `limit N` in mysql or postgres, `top(N)` in sqlserver , `FETCH FIRST %S ROWS ONLY` in DB2.

Specified by:

queryNextChunkMax in class JdbcSourceChunkSplitter

Parameters:

jdbc - JDBC connection.

tableId - table identity.

column - column.

chunkSize - chunk size.

includedLowerBound - the previous chunk end value.

Returns:

next chunk end value.

Throws:

SQLException

queryApproximateRowCnt

protected Long queryApproximateRowCnt(io.debezium.jdbc.JdbcConnection jdbc,
                                      io.debezium.relational.TableId tableId)
                               throws SQLException

Description copied from class: JdbcSourceChunkSplitter

Approximate total number of entries in the lookup table.

Each database has different system table to lookup up approximate total number. For example, `pg_class` in postgres, `sys.dm_db_partition_stats` in sqlserver, `SYSCAT.TABLE` in db2.

Specified by:

queryApproximateRowCnt in class JdbcSourceChunkSplitter

Parameters:

jdbc - JDBC connection.

tableId - table identity.

Returns:

approximate row count.

Throws:

SQLException