Deploying the MySQL connector

Installing the MySQL connector

Installing the Debezium MySQL connector is a simple process whereby you only need to download the JAR, extract it to your Kafka Connect environment, and ensure the plugin’s parent directory is specified in your Kafka Connect environment.

Prerequisites
Procedure
  1. Download the Debezium MySQL connector plugin.

  2. Extract the files into your Kafka Connect environment.

  3. Add the plugin’s parent directory to your Kafka Connect plugin path:

plugin.path=/kafka/connect
The above example assumes you have extracted the Debezium MySQL connector to the /kafka/connect/Debezium-connector-mysql path.
  1. Restart your Kafka Connect process. This ensures the new JARs are picked up.

Configuring the MySQL connector

Typically, you configure the Debezium MySQL connector in a JSON file using the configuration properties available for the connector.

Prerequisites
Procedure
  1. Set the "name" of the connector in the JSON file.

  2. Set the configuration properties that you require for your Debezium MySQL connector.

For a complete list of configuration properties, see MySQL connector configuration properties.
Example 1. MySQL connector example configuration
{
  "name": "inventory-connector", (1)
  "config": {
    "connector.class": "io.debezium.connector.mysql.MySqlConnector", (2)
    "database.hostname": "192.168.99.100", (3)
    "database.port": "3306", (4)
    "database.user": "{prodname}-user", (5)
    "database.password": "thePassword", (6)
    "database.server.id": "184054", (7)
    "database.server.name": "fullfillment", (8)
    "database.whitelist": "inventory", (9)
    "database.history.kafka.bootstrap.servers": "kafka:9092", (10)
    "database.history.kafka.topic": "dbhistory.fullfillment", (11)
    "include.schema.changes": "true" (12)
  }
}

Example configuration properties explained

  1. The connector’s name when registered with the Kafka Connect service.

  2. The connector’s class name.

  3. The MySQL server address.

  4. The MySQL server port number.

  5. The MySQL user with the appropriate privileges.

  6. The MySQL user’s password.

  7. The unique ID of the connector.

  8. The logical name of the MySQL server or cluster.

  9. A list of all databases hosted by the specified server.

  10. A list of Kafka brokers that the connector uses to write and recover DDL statements to the database history topic.

  11. The name of the database history topic.

  12. The flag that specifies if the connector should generate on the schema change topic named fulfillment events with DDL changes that can be used by consumers.

MySQL connector configuration properties

The configuration properties listed here are required to run the Debezium MySQL connector. There are also advanced MySQL connector properties whose default value rarely need changed and therefore, specified in the connector configuration.

The Debezium MySQL connector supports pass-through configuration when creating the Kafka producer and consumer. See the Kafka documentation for more details on pass-through properties.
Property Default Description

name

Unique name for the connector. Attempting to register again with the same name will fail. (This property is required by all Kafka Connect connectors.)

connector.class

The name of the Java class for the connector. Always use a value of io.debezium​.connector.mysql.MySqlConnector for the MySQL connector.

tasks.max

1

The maximum number of tasks that should be created for this connector. The MySQL connector always uses a single task and therefore does not use this value, so the default is always acceptable.

database.hostname

IP address or hostname of the MySQL database server.

database.port

3306

Integer port number of the MySQL database server.

database.user

Name of the MySQL database to use when connecting to the MySQL database server.

database.password

Password to use when connecting to the MySQL database server.

database.server.name

Logical name that identifies and provides a namespace for the particular MySQL database server/cluster being monitored. The logical name should be unique across all other connectors, since it is used as a prefix for all Kafka topic names emanating from this connector. Only alphanumeric characters and underscores should be used.

database.server.id

random

A numeric ID of this database client, which must be unique across all currently-running database processes in the MySQL cluster. This connector joins the MySQL database cluster as another server (with this unique ID) so it can read the binlog. By default, a random number is generated between 5400 and 6400, though we recommend setting an explicit value.

database.history.kafka.topic

The full name of the Kafka topic where the connector will store the database schema history.

database.history​.kafka.bootstrap.servers

A list of host/port pairs that the connector will use for establishing an initial connection to the Kafka cluster. This connection will be used for retrieving database schema history previously stored by the connector, and for writing each DDL statement read from the source database. This should point to the same Kafka cluster used by the Kafka Connect process.

database.whitelist

empty string

An optional comma-separated list of regular expressions that match database names to be monitored; any database name not included in the whitelist will be excluded from monitoring. By default all databases will be monitored. May not be used with database.blacklist.

database.blacklist

empty string

An optional comma-separated list of regular expressions that match database names to be excluded from monitoring; any database name not included in the blacklist will be monitored. May not be used with database.whitelist.

table.whitelist

empty string

An optional comma-separated list of regular expressions that match fully-qualified table identifiers for tables to be monitored; any table not included in the whitelist will be excluded from monitoring. Each identifier is of the form databaseName.tableName. By default the connector will monitor every non-system table in each monitored database. May not be used with table.blacklist.

table.blacklist

empty string

An optional comma-separated list of regular expressions that match fully-qualified table identifiers for tables to be excluded from monitoring; any table not included in the blacklist will be monitored. Each identifier is of the form databaseName.tableName. May not be used with table.whitelist.

column.blacklist

empty string

An optional comma-separated list of regular expressions that match the fully-qualified names of columns that should be excluded from change event message values. Fully-qualified names for columns are of the form databaseName.tableName.columnName, or databaseName.schemaName.tableName.columnName.

column.truncate.to.length.chars

n/a

An optional comma-separated list of regular expressions that match the fully-qualified names of character-based columns whose values should be truncated in the change event message values if the field values are longer than the specified number of characters. Multiple properties with different lengths can be used in a single configuration, although in each the length must be a positive integer. Fully-qualified names for columns are of the form databaseName.tableName.columnName, or databaseName.schemaName.tableName.columnName.

column.mask.with.length.chars

n/a

An optional comma-separated list of regular expressions that match the fully-qualified names of character-based columns whose values should be replaced in the change event message values with a field value consisting of the specified number of asterisk (*) characters. Multiple properties with different lengths can be used in a single configuration, although in each the length must be a positive integer or zero. Fully-qualified names for columns are of the form databaseName.tableName.columnName, or databaseName.schemaName.tableName.columnName.

column.propagate.source.type

n/a

An optional comma-separated list of regular expressions that match the fully-qualified names of columns whose original type and length should be added as a parameter to the corresponding field schemas in the emitted change messages. The schema parameters __Debezium.source.column.type, __Debezium.source.column.length and _Debezium.source.column.scale will be used to propagate the original type name and length (for variable-width types), respectively. Useful to properly size corresponding columns in sink databases. Fully-qualified names for columns are of the form databaseName.tableName.columnName, or databaseName.schemaName.tableName.columnName.

datatype.propagate.source.type

n/a

An optional comma-separated list of regular expressions that match the database-specific data type name of columns whose original type and length should be added as a parameter to the corresponding field schemas in the emitted change messages. The schema parameters __debezium.source.column.type, __debezium.source.column.length and __debezium.source.column.scale will be used to propagate the original type name and length (for variable-width types), respectively. Useful to properly size corresponding columns in sink databases. Fully-qualified data type names are of the form databaseName.tableName.typeName, or databaseName.schemaName.tableName.typeName. See [data-types] for the list of MySQL-specific data type names.

time.precision.mode

adaptive_time​_microseconds

Time, date, and timestamps can be represented with different kinds of precision, including: adaptive_time_microseconds (the default) captures the date, datetime and timestamp values exactly as in the database using either millisecond, microsecond, or nanosecond precision values based on the database column’s type, with the exception of TIME type fields, which are always captured as microseconds; adaptive (deprecated) captures the time and timestamp values exactly as in the database using either millisecond, microsecond, or nanosecond precision values based on the database column’s type; or connect always represents time and timestamp values using Kafka Connect’s built-in representations for Time, Date, and Timestamp, which uses millisecond precision regardless of the database columns' precision.

decimal.handling.mode

precise

Specifies how the connector should handle values for DECIMAL and NUMERIC columns: precise (the default) represents them precisely using java.math.BigDecimal values represented in change events in a binary form; or double represents them using double values, which may result in a loss of precision but will be far easier to use. string option encodes values as formatted string which is easy to consume but a semantic information about the real type is lost.

bigint.unsigned.handling.mode

long

Specifies how BIGINT UNSIGNED columns should be represented in change events, including: precise uses java.math.BigDecimal to represent values, which are encoded in the change events using a binary representation and Kafka Connect’s org.apache.kafka.connect.data.Decimal type; long (the default) represents values using Java’s long, which may not offer the precision but will be far easier to use in consumers. long is usually the preferable setting. Only when working with values larger than 2^63, the precise setting should be used as those values can’t be conveyed using long.

include.schema.changes

true

Boolean value that specifies whether the connector should publish changes in the database schema to a Kafka topic with the same name as the database server ID. Each schema change will be recorded using a key that contains the database name and whose value includes the DDL statement(s). This is independent of how the connector internally records database history. The default is true.

include.query

false

Boolean value that specifies whether the connector should include the original SQL query that generated the change event.
Note: This option requires MySQL be configured with the binlog_rows_query_log_events option set to ON. Query will not be present for events generated from the snapshot process.
WARNING: Enabling this option may expose tables or fields explicitly blacklisted or masked by including the original SQL statement in the change event. For this reason this option is defaulted to 'false'.

event.processing​.failure.handling.mode

fail

Specifies how the connector should react to exceptions during deserialization of binlog events. fail will propagate the exception (indicating the problematic event and its binlog offset), causing the connector to stop.
warn will cause the problematic event to be skipped and the problematic event and its binlog offset to be logged.
skip will cause problematic event will be skipped.

inconsistent.schema.handling.mode

fail

Specifies how the connector should react to binlog events that relate to tables that are not present in internal schema representation (i.e. internal representation is not consistent with database) fail will throw an exception (indicating the problematic event and its binlog offset), causing the connector to stop.
warn will cause the problematic event to be skipped and the problematic event and its binlog offset to be logged.
skip will cause the problematic event to be skipped.

max.queue.size

8192

Positive integer value that specifies the maximum size of the blocking queue into which change events read from the database log are placed before they are written to Kafka. This queue can provide backpressure to the binlog reader when, for example, writes to Kafka are slower or if Kafka is not available. Events that appear in the queue are not included in the offsets periodically recorded by this connector. Defaults to 8192, and should always be larger than the maximum batch size specified in the max.batch.size property.

max.batch.size

2048

Positive integer value that specifies the maximum size of each batch of events that should be processed during each iteration of this connector. Defaults to 2048.

poll.interval.ms

1000

Positive integer value that specifies the number of milliseconds the connector should wait during each iteration for new change events to appear. Defaults to 1000 milliseconds, or 1 second.

connect.timeout.ms

30000

A positive integer value that specifies the maximum time in milliseconds this connector should wait after trying to connect to the MySQL database server before timing out. Defaults to 30 seconds.

gtid.source.includes

A comma-separated list of regular expressions that match source UUIDs in the GTID set used to find the binlog position in the MySQL server. Only the GTID ranges that have sources matching one of these include patterns will be used. May not be used with gtid.source.excludes.

gtid.source.excludes

A comma-separated list of regular expressions that match source UUIDs in the GTID set used to find the binlog position in the MySQL server. Only the GTID ranges that have sources matching none of these exclude patterns will be used. May not be used with gtid.source.includes.

gtid.new.channel.position
deprecated and scheduled for removal

earliest

When set to latest, when the connector sees a new GTID channel, it will start consuming from the last executed transaction in that GTID channel. If set to earliest (default), the connector starts reading that channel from the first available (not purged) GTID position. earliest is useful when you have a active-passive MySQL setup where Debezium is connected to master, in this case during failover the slave with new UUID (and GTID channel) starts receiving writes before Debezium is connected. These writes would be lost when using latest.

tombstones.on.delete

true

Controls whether a tombstone event should be generated after a delete event.
When true the delete operations are represented by a delete event and a subsequent tombstone event. When false only a delete event is sent.
Emitting the tombstone event (the default behavior) allows Kafka to completely delete all events pertaining to the given key once the source record got deleted.

message.key.columns

empty string

A semi-colon list of regular expressions that match fully-qualified tables and columns to map a primary key.
Each item (regular expression) must match the <fully-qualified table>:<a comma-separated list of columns> representing the custom key.
Fully-qualified tables could be defined as DB_NAME.TABLE_NAME or SCHEMA_NAME.TABLE_NAME, depending on the specific connector.

Advanced MySQL connector properties

Property Default Description

connect.keep.alive

true

A boolean value that specifies whether a separate thread should be used to ensure the connection to the MySQL server/cluster is kept alive.

table.ignore.builtin

true

Boolean value that specifies whether built-in system tables should be ignored. This applies regardless of the table whitelist or blacklists. By default system tables are excluded from monitoring, and no events are generated when changes are made to any of the system tables.

database.history.kafka.recovery.poll.interval.ms

100

An integer value that specifies the maximum number of milliseconds the connector should wait during startup/recovery while polling for persisted data. The default is 100ms.

database.history.kafka.recovery.attempts

4

The maximum number of times that the connector should attempt to read persisted history data before the connector recovery fails with an error. The maximum amount of time to wait after receiving no data is recovery.attempts x recovery.poll.interval.ms.

database.history.skip.unparseable.ddl

false

Boolean value that specifies if connector should ignore malformed or unknown database statements or stop processing and let operator to fix the issue. The safe default is false. Skipping should be used only with care as it can lead to data loss or mangling when binlog is processed.

database.history.store.only.monitored.tables.ddl

false

Boolean value that specifies if connector should should record all DDL statements or (when true) only those that are relevant to tables that are monitored by Debezium (via filter configuration). The safe default is false. This feature should be used only with care as the missing data might be necessary when the filters are changed.

database.ssl.mode

disabled

Specifies whether to use an encrypted connection. The default is disabled, and specifies to use an unencrypted connection.

The preferred option establishes an encrypted connection if the server supports secure connections but falls back to an unencrypted connection otherwise.

The required option establishes an encrypted connection but will fail if one cannot be made for any reason.

The verify_ca option behaves like required but additionally it verifies the server TLS certificate against the configured Certificate Authority (CA) certificates and will fail if it doesn’t match any valid CA certificates.

The verify_identity option behaves like verify_ca but additionally verifies that the server certificate matches the host of the remote connection.

binlog.buffer.size

0

The size of a look-ahead buffer used by the binlog reader.
Under specific conditions it is possible that MySQL binlog contains uncommitted data finished by a ROLLBACK statement. Typical examples are using savepoints or mixing temporary and regular table changes in a single transaction.
When a beginning of a transaction is detected then Debezium tries to roll forward the binlog position and find either COMMIT or ROLLBACK so it can decide whether the changes from the transaction will be streamed or not. The size of the buffer defines the maximum number of changes in the transaction that Debezium can buffer while searching for transaction boundaries. If the size of transaction is larger than the buffer then Debezium needs to rewind and re-read the events that has not fit into the buffer while streaming. Value 0 disables buffering.
Disabled by default.
Note: This feature should be considered an incubating one. We need a feedback from customers but it is expected that it is not completely polished.

snapshot.mode

initial

Specifies the criteria for running a snapshot upon startup of the connector. The default is initial, and specifies the connector can run a snapshot only when no offsets have been recorded for the logical server name. The when_needed option specifies that the connector run a snapshot upon startup whenever it deems it necessary (when no offsets are available, or when a previously recorded offset specifies a binlog location or GTID that is not available in the server). The never option specifies that the connect should never use snapshots and that upon first startup with a logical server name the connector should read from the beginning of the binlog; this should be used with care, as it is only valid when the binlog is guaranteed to contain the entire history of the database. If you don’t need the topics to contain a consistent snapshot of the data but only need them to have the changes since the connector was started, you can use the schema_only option, where the connector only snapshots the schemas (not the data).

schema_only_recovery is a recovery option for an existing connector to recover a corrupted or lost database history topic, or to periodically "clean up" a database history topic (which requires infinite retention) that may be growing unexpectedly.

snapshot.locking.mode

minimal

Controls if and how long the connector holds onto the global MySQL read lock (preventing any updates to the database) while it is performing a snapshot. There are three possible values minimal, extended, and none.

minimal The connector holds the global read lock for just the initial portion of the snapshot while the connector reads the database schemas and other metadata. The remaining work in a snapshot involves selecting all rows from each table, and this can be done in a consistent fashion using the REPEATABLE READ transaction even when the global read lock is no longer held and while other MySQL clients are updating the database.

extended In some cases where clients are submitting operations that MySQL excludes from REPEATABLE READ semantics, it may be desirable to block all writes for the entire duration of the snapshot. For these such cases, use this option.

none Will prevent the connector from acquiring any table locks during the snapshot process. This value can be used with all snapshot modes but it is safe to use if and only if no schema changes are happening while the snapshot is taken. Note that for tables defined with MyISAM engine, the tables would still be locked despite this property being set as MyISAM acquires a table lock. This behaviour is unlike InnoDB engine which acquires row level locks.

snapshot.select.statement.overrides

Controls which rows from tables will be included in snapshot.
This property contains a comma-separated list of fully-qualified tables (DB_NAME.TABLE_NAME). Select statements for the individual tables are specified in further configuration properties, one for each table, identified by the id snapshot.select.statement.overrides.[DB_NAME].[TABLE_NAME]. The value of those properties is the SELECT statement to use when retrieving data from the specific table during snapshotting. A possible use case for large append-only tables is setting a specific point where to start (resume) snapshotting, in case a previous snapshotting was interrupted.
Note: This setting has impact on snapshots only. Events captured from binlog are not affected by it at all.

min.row.count.to.stream.results

1000

During a snapshot operation, the connector will query each included table to produce a read event for all rows in that table. This parameter determines whether the MySQL connection will pull all results for a table into memory (which is fast but requires large amounts of memory), or whether the results will instead be streamed (can be slower, but will work for very large tables). The value specifies the minimum number of rows a table must contain before the connector will stream results, and defaults to 1,000. Set this parameter to '0' to skip all table size checks and always stream all results during a snapshot.

heartbeat.interval.ms

0

Controls how frequently the heartbeat messages are sent.
This property contains an interval in milli-seconds that defines how frequently the connector sends heartbeat messages into a heartbeat topic. Set this parameter to 0 to not send heartbeat messages at all.
Disabled by default.

heartbeat.topics.prefix

__debezium-heartbeat

Controls the naming of the topic to which heartbeat messages are sent.
The topic is named according to the pattern <heartbeat.topics.prefix>.<server.name>.

database.initial.statements

A semicolon separated list of SQL statements to be executed when a JDBC connection (not the transaction log reading connection) to the database is established. Use doubled semicolon (';;') to use a semicolon as a character and not as a delimiter.
Note: The connector may establish JDBC connections at its own discretion, so this should typically be used for configuration of session parameters only, but not for executing DML statements.

snapshot.delay.ms

An interval in milli-seconds that the connector should wait before taking a snapshot after starting up;
Can be used to avoid snapshot interruptions when starting multiple connectors in a cluster, which may cause re-balancing of connectors.

snapshot.fetch.size

Specifies the maximum number of rows that should be read in one go from each table while taking a snapshot. The connector will read the table contents in multiple batches of this size.

snapshot.lock.timeout.ms

10000

Positive integer value that specifies the maximum amount of time (in milliseconds) to wait to obtain table locks when performing a snapshot. If table locks cannot be acquired in this time interval, the snapshot will fail. See snapshots

enable.time.adjuster

MySQL allows user to insert year value as either 2-digit or 4-digit. In case of two digits the value is automatically mapped to 1970 - 2069 range. This is usually done by database.
Set to true (the default) when Debezium should do the conversion.
Set to false when conversion is fully delegated to the database.

source.struct.version

v2

Schema version for the source block in Debezium events; Debezium 0.10 introduced a few breaking
changes to the structure of the source block in order to unify the exposed structure across all the connectors.
By setting this option to v1 the structure used in earlier versions can be produced. Note that this setting is not recommended and is planned for removal in a future Debezium version.

sanitize.field.names

true when connector configuration explicitly specifies the key.converter or value.converter parameters to use Avro, otherwise defaults to false.

Whether field names will be sanitized to adhere to Avro naming requirements.

MySQL connector monitoring metrics

The Debezium MySQL connector has three metric types in addition to the built-in support for JMX metrics that Zookeeper, Kafka, and Kafka Connect have.

Snapshot metrics

The MBean is debezium.mysql:type=connector-metrics,context=snapshot,server=<database.server.name>.

Attribute Type Description

TotalTableCount

int

The total number of tables that are being included in the snapshot.

RemainingTableCount

int

The number of tables that the snapshot has yet to copy.

HoldingGlobalLock

boolean

Whether the connector currently holds a global or table write lock.

SnapshotRunning

boolean

Whether the snapshot was started.

SnapshotAborted

boolean

Whether the snapshot was aborted.

SnapshotCompleted

boolean

Whether the snapshot completed.

SnapshotDurationInSeconds

long

The total number of seconds that the snapshot has taken so far, even if not complete.

RowsScanned

Map<String, Long>

Map containing the number of rows scanned for each table in the snapshot. Tables are incrementally added to the Map during processing. Updates every 10,000 rows scanned and upon completing a table.

LastEvent

string

The last snapshot event that the connector has read.

MilliSecondsSinceLastEvent

long

The number of milliseconds since the connector has read and processed the most recent event.

TotalNumberOfEventsSeen

long

The total number of events that this connector has seen since last started or reset.

NumberOfEventsFiltered

long

The number of events that have been filtered by whitelist or blacklist filtering rules configured on the connector.

MonitoredTables

string[]

The list of tables that are monitored by the connector.

QueueTotalCapcity

int

The length of the queue used to pass events between snapshot reader and the main Kafka Connect loop.

QueueRemainingCapcity

int

The free capacity of the queue used to pass events between snapshot reader and the main Kafka Connect loop.

Binlog metrics

The MBean is debezium.mysql:type=connector-metrics,context=binlog,server=<database.server.name>.

The transaction-related attributes are only available if binlog event buffering is enabled. See binlog.buffer.size in the advanced connector configuration properties for more details.
Attribute Type Description

Connected

boolean

Flag that denotes whether the connector is currently connected to the MySQL server.

BinlogFilename

string

The name of the binlog filename that the connector has most recently read.

BinlogPosition

long

The most recent position (in bytes) within the binlog that the connector has read.

IsGtidModeEnabled

boolean

Flag that denotes whether the connector is currently tracking GTIDs from MySQL server.

GtidSet

string

The string representation of the most recent GTID set seen by the connector when reading the binlog.

LastEvent

string

The last binlog event that the connector has read.

SecondsSinceLastEvent (obsolete)

long

The number of seconds since the connector has read and processed the most recent event.

SecondsBehindMaster (obsolete)

long

The number of seconds between the last event’s MySQL timestamp and the connector processing it. The values will incorporate any differences between the clocks on the machines where the MySQL server and the MySQL connector are running.

MilliSecondsBehindSource

long

The number of milliseconds between the last event’s MySQL timestamp and the connector processing it. The values will incorporate any differences between the clocks on the machines where the MySQL server and the MySQL connector are running.

TotalNumberOfEventsSeen

long

The total number of events that this connector has seen since last started or reset.

NumberOfSkippedEvents

long

The number of events that have been skipped by the MySQL connector. Typically events are skipped due to a malformed or unparseable event from MySQL’s binlog.

NumberOfEventsFiltered

long

The number of events that have been filtered by whitelist or blacklist filtering rules configured on the connector.

NumberOfDisconnects

long

The number of disconnects by the MySQL connector.

SourceEventPosition

map<string, string>

The coordinates of the last received event.

LastTransactionId

string

Transaction identifier of the last processed transaction.

LastEvent

string

The last binlog event that the connector has read.

MilliSecondsSinceLastEvent

long

The number of milliseconds since the connector has read and processed the most recent event.

MonitoredTables

string[]

The list of tables that are monitored by Debezium.

QueueTotalCapcity

int

The length of the queue used to pass events between binlog reader and the main Kafka Connect loop.

QueueRemainingCapcity

int

The free capacity of the queue used to pass events between binlog reader and the main Kafka Connect loop.

NumberOfCommittedTransactions

long

The number of processed transactions that were committed.

NumberOfRolledBackTransactions

long

The number of processed transactions that were rolled back and not streamed.

NumberOfNotWellFormedTransactions

long

The number of transactions that have not conformed to expected protocol BEGIN + COMMIT/ROLLBACK. Should be 0 under normal conditions.

NumberOfLargeTransactions

long

The number of transactions that have not fitted into the look-ahead buffer. Should be significantly smaller than NumberOfCommittedTransactions and NumberOfRolledBackTransactions for optimal performance.

Schema history metrics

The MBean is debezium.mysql:type=connector-metrics,context=schema-history,server=<database.server.name>.

Attribute Type Description

Status

string

One of STOPPED, RECOVERING (recovering history from the storage), RUNNING describing state of the database history.

RecoveryStartTime

long

The time in epoch seconds at what recovery has started.

ChangesRecovered

long

The number of changes that were read during recovery phase.

ChangesApplied

long

The total number of schema changes applie during recovery and runtime.

MilliSecondsSinceLastRecoveredChange

long

The number of milliseconds that elapsed since the last change was recovered from the history store.

MilliSecondsSinceLastAppliedChange

long

The number of milliseconds that elapsed since the last change was applied.

LastRecoveredChange

string

The string representation of the last change recovered from the history store.

LastAppliedChange

string

The string representation of the last applied change.