org.apache.hudi.common.table.cdc

Enum HoodieCDCInferenceCase

java.lang.Object

java.lang.Enum<HoodieCDCInferenceCase>

org.apache.hudi.common.table.cdc.HoodieCDCInferenceCase

All Implemented Interfaces:

Serializable, Comparable<HoodieCDCInferenceCase>

public enum HoodieCDCInferenceCase
extends Enum<HoodieCDCInferenceCase>

Here define five cdc infer cases. The different cdc infer case will decide which file will be used to extract the change data, and how to do this. AS_IS: For this type, there must be a real cdc log file from which we get the whole/part change data. when `hoodie.table.cdc.supplemental.logging.mode` is HoodieCDCSupplementalLoggingMode.DATA_BEFORE_AFTER, it keeps all the fields about the change data, including `op`, `ts_ms`, `before` and `after`. So read it and return directly, no more other files need to be loaded. when `hoodie.table.cdc.supplemental.logging.mode` is HoodieCDCSupplementalLoggingMode.DATA_BEFORE, it keeps the `op`, the key and the `before` of the changing record. When `op` is equal to 'i' or 'u', need to get the current record from the current base/log file as `after`. when `hoodie.table.cdc.supplemental.logging.mode` is 'op_key', it just keeps the `op` and the key of the changing record. When `op` is equal to 'i', `before` is null and get the current record from the current base/log file as `after`. When `op` is equal to 'u', get the previous record from the previous file slice as `before`, and get the current record from the current base/log file as `after`. When `op` is equal to 'd', get the previous record from the previous file slice as `before`, and `after` is null. BASE_FILE_INSERT: For this type, there must be a base file at the current instant. All the records from this file is new-coming, so we can load this, mark all the records with `i`, and treat them as the value of `after`. The value of `before` for each record is null. BASE_FILE_DELETE: For this type, there must be an empty file at the current instant, but a non-empty base file at the previous instant. First we find this base file that has the same file group and belongs to the previous instant. Then load this, mark all the records with `d`, and treat them as the value of `before`. The value of `after` for each record is null. LOG_FILE: For this type, a normal log file of mor table will be used. First we need to load the previous file slice(including the base file and other log files in the same file group). Then for each record from the log file, get the key of this, and execute the following steps: 1) if the record is deleted, a) if there is a record with the same key in the data loaded, `op` is 'd', 'before' is the record from the data loaded, `after` is null; b) if there is not a record with the same key in the data loaded, just skip. 2) the record is not deleted, a) if there is a record with the same key in the data loaded, `op` is 'u', 'before' is the record from the data loaded, `after` is the current record; b) if there is not a record with the same key in the data loaded, `op` is 'i', 'before' is null, `after` is the current record; REPLACE_COMMIT: For this type, it must be a replacecommit, like INSERT_OVERWRITE and DROP_PARTITION. It drops a whole file group. First we find this file group. Then load this, mark all the records with `d`, and treat them as the value of `before`. The value of `after` for each record is null.

Enum Constant Summary

Enum Constants

Enum Constant and Description
AS_IS
BASE_FILE_DELETE
BASE_FILE_INSERT
LOG_FILE
REPLACE_COMMIT

Method Summary

Modifier and Type	Method and Description
static HoodieCDCInferenceCase	valueOf(String name) Returns the enum constant of this type with the specified name.
static HoodieCDCInferenceCase[]	values() Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Detail

AS_IS

public static final HoodieCDCInferenceCase AS_IS

BASE_FILE_INSERT

public static final HoodieCDCInferenceCase BASE_FILE_INSERT

BASE_FILE_DELETE

public static final HoodieCDCInferenceCase BASE_FILE_DELETE

LOG_FILE

public static final HoodieCDCInferenceCase LOG_FILE

REPLACE_COMMIT

public static final HoodieCDCInferenceCase REPLACE_COMMIT

Method Detail

values

public static HoodieCDCInferenceCase[] values()

Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:

for (HoodieCDCInferenceCase c : HoodieCDCInferenceCase.values())
    System.out.println(c);

Returns:

an array containing the constants of this enum type, in the order they are declared

valueOf

public static HoodieCDCInferenceCase valueOf(String name)

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

IllegalArgumentException - if this enum type has no constant with the specified name

NullPointerException - if the argument is null