See Section 2.18.9, “Other Limitations” for all HeatWave query related limitations. Before MySQL 8.3.0, not all queries could be accelerated by HeatWave Lakehouse, and a warning or error message was displayed.
Do not create Lakehouse tables on the source DB in a replicated MySQL DB System if any of the replicas are outside HeatWave on OCI or HeatWave on AWS. This will cause replication errors.
Before MySQL 8.4.0-u2, a replication channel might fail if a HeatWave Cluster is added to a replica of a MySQL DB System, and later manually stopped.
It is not possible to dump external tables using the MySQL Shell export utilities, such as
dumpInstance()
. External tables are not replicated to InnoDB storage and cannot be exported. To export InnoDB data from a Lakehouse enabled database, exclude the external tables with anexcludeTables
option.It is not possible to restore a backup from a Lakehouse enabled MySQL DB System to a standalone MySQL DB System.
A Lakehouse enabled MySQL DB System can support a maximum of 512 nodes.
Before MySQL 8.4.0, Lakehouse does not enforce any specified constraints. For example, Lakehouse does not enforce primary key uniqueness constraints. MySQL 8.4.0 removes this limitation.
-
HeatWave Lakehouse does not support the following:
-
DML statements:
The
CREATE TABLESPACE
statement.-
The following options for the
CREATE TABLE
statement:AUTOEXTEND_SIZE
AVG_ROW_LENGTH
CHECKSUM
COMPRESS
CONNECTION
DATADIR
DELAY_KEY_WRITE
ENCRYPT
INDEXDIR
INSERT_METHOD
KEY_BLOCK_SIZE
MAX_ROWS
MIN_ROWS
PACK_KEYS
PASSWORD
ROW_FORMAT
STATS_AUTO_RECALC
STATS_PERSISTENT
STATS_SAMPLE_PAGES
UNION
The default expression for a column definition for the
CREATE TABLE
statement.Creating temporary tables.
-
Creating
AUTO_INCREMENT
columns.Therefore, Lakehouse is not compatible with
REQUIRE_TABLE_PRIMARY_KEY_CHECK
=GENERATE
. Creating triggers.
Running
ANALYZE TABLE
.Running
ALTER TABLE
statements that construct indexes,ADD
orDROP
columns, or add enforced check constraints.SELECT
statements withoutRAPID
as the secondary engine.Hidden columns.
Index construction.
Keys with column prefixes.
Running any statement with a
STORAGE
clause.The use of
CURRENT_TIMESTAMP()
,CURRENT_TIMESTAMP
orNOW()
as a default value for a timestamp column. Also anUPDATE
statement withCURRENT_TIMESTAMP()
,CURRENT_TIMESTAMP
orNOW()
. Enableexplicit_defaults_for_timestamp
to useALTER TABLE
andCREATE TABLE
statements with Lakehouse tables that have a timestamp column.-
The following limitations only apply up to MySQL 8.3.0-u2. MySQL 8.3.0-u2 removes these limitations:
Point-in-time-recovery. A MySQL DB System is created with point-in-time-recovery enabled by default. To enable Lakehouse, disable point-in-time-recovery.
High Availability. To enable Lakehouse, disable High Availability or create a standalone MySQL DB System for use with Lakehouse.
Read Replication.
Outbound Replication.
NoteWhen disabling Read Replicas, High Availability, or Outbound Replication on a MySQL DB System to enable Lakehouse, it is recommended to wait several minutes before enabling Lakehouse. This allows replication processes to complete their tasks and for the binlog dump threads to stop.
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