MySQL HeatWave User Guide
MySQL HeatWave Lakehouse has the following limitations for all file formats. Review Other Limitations for all MySQL HeatWave query-related limitations.
MySQL 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 or DROP
columns, or add enforced check constraints.
SELECT statements without
RAPID as the secondary engine.
Hidden columns.
Index construction.
Keys with column prefixes.
Running CREATE TABLE or
ALTER TABLE statement
containing a STORAGE clause in the
column attributes of a Lakehouse table.
The use of
CURRENT_TIMESTAMP(),
CURRENT_TIMESTAMP or
NOW() as a default value
for a timestamp column. Also an
UPDATE statement with
CURRENT_TIMESTAMP(),
CURRENT_TIMESTAMP or
NOW(). Enable
explicit_defaults_for_timestamp
to use ALTER TABLE and
CREATE TABLE statements
with Lakehouse tables that have a timestamp column.
A zone map on a JSON column.
MySQL HeatWave Lakehouse has the following limitations:
As of MySQL 9.3.1, Lakehouse tables have the following column width limitations based on data type:
MEDIUMTEXT,
LONGTEXT, and
JSON: 4192192 bytes
TEXT: 65535 bytes
CHAR, VARCHAR,
and VECTOR: 65532 bytes
Column width limitations apply after Lakehouse extracts and cleans data from files, and in the case of JSON data after converting it into JSON DOM representation internally.
The maximum row width is 4 MB. This includes the size of all the data and column metadata stored in the row. You cannot load a Lakehouse table that has multiple columns with a combined data size greater than 4 MB. This applies to intermediate relations and final query results as well.
Before MySQL 9.3.1, the maximum column width is 65532 bytes.
Do not create Lakehouse tables on the source DB in a replicated DB System if any of the replicas are outside MySQL HeatWave on OCI or MySQL HeatWave on AWS. This causes replication errors.
Before MySQL 8.4.0-u2, a replication channel might fail if a MySQL HeatWave Cluster is added to a replica of a DB System, and later manually stopped.
It is not possible to dump external tables using the
MySQL Shell export utilities, such as
dumpInstance(). External Lakehouse
tables are not replicated to DB System storage and cannot
be exported. To export DB System data from a Lakehouse
enabled database, exclude the external tables with an
excludeTables option.
It is not possible to restore a backup from a Lakehouse enabled DB System to a standalone DB System.
A Lakehouse enabled DB System can support a maximum of 512 nodes.
Before MySQL 8.4.0, Lakehouse does not enforce any
specified constraints on primary key, unique key,
foreign key, and CHECK constraints.
MySQL 8.4.0 removes this limitation for primary key and
unique key constraints.
Before MySQL 9.0.1-u1, the limit for the Lakehouse
error message count is 100. As of MySQL 9.0.1-u1,
Lakehouse supports
max_error_count.
The
lakehouse_filter_warning_codes_list
session variable has a limit of 50 codes and 250
characters.
MySQL HeatWave Lakehouse does not support the following: