Spider System Variables
The following variables are available when the Spider storage engine has been installed.
See Server System Variables for a complete list of system variables and instructions on setting them.
See also the Full list of MariaDB options, system and status variables.
MariaDB starting with 10.4.31
Starting from MariaDB 10.4.31, MariaDB 10.5.22, MariaDB 10.6.15, MariaDB 10.9.8, MariaDB 10.10.6, MariaDB 10.11.5, MariaDB 11.0.3, all spider system variables with the value -1 for deferring to table parameter values follow the correct overriding mechanism: table parameter (if set) overrides system variables (if not -1) overrides actual variable default. As a side effect, all such system variables in all versions have the same default value as the table param default value.
Before this change, a non-minus-one system variable value would override the table parameter value. That is, if both the system variable value and the table parameter value were set to be non-minus-one, the system variable value would prevail. For MariaDB 10.7+ where the system variable default values were the same as table param default instead of -1, this means that if the system variable were not set, but a table param is set to a non-default value, the default would override the non-default value.
Contents
- spider_auto_increment_mode
- spider_bgs_first_read
- spider_bgs_mode
- spider_bgs_second_read
- spider_bka_engine
- spider_bka_mode
- spider_bka_table_name_type
- spider_block_size
- spider_buffer_size
- spider_bulk_size
- spider_bulk_update_mode
- spider_bulk_update_size
- spider_casual_read
- spider_conn_recycle_mode
- spider_conn_recycle_strict
- spider_conn_wait_timeout
- spider_connect_error_interval
- spider_connect_mutex
- spider_connect_retry_count
- spider_connect_retry_interval
- spider_connect_timeout
- spider_crd_bg_mode
- spider_crd_interval
- spider_crd_mode
- spider_crd_sync
- spider_crd_type
- spider_crd_weight
- spider_delete_all_rows_type
- spider_direct_dup_insert
- spider_direct_order_limit
- spider_disable_group_by_handler
- spider_dry_access
- spider_error_read_mode
- spider_error_write_mode
- spider_first_read
- spider_force_commit
- spider_general_log
- spider_ignore_comments
- spider_index_hint_pushdown
- spider_init_sql_alloc_size
- spider_internal_limit
- spider_internal_offset
- spider_internal_optimize
- spider_internal_optimize_local
- spider_internal_sql_log_off
- spider_internal_unlock
- spider_internal_xa
- spider_internal_xa_id_type
- spider_internal_xa_snapshot
- spider_load_crd_at_startup
- spider_load_sts_at_startup
- spider_local_lock_table
- spider_lock_exchange
- spider_log_result_error_with_sql
- spider_log_result_errors
- spider_low_mem_read
- spider_max_connections
- spider_max_order
- spider_multi_split_read
- spider_net_read_timeout
- spider_net_write_timeout
- spider_ping_interval_at_trx_start
- spider_quick_mode
- spider_quick_page_byte
- spider_quick_page_size
- spider_read_only_mode
- spider_remote_access_charset
- spider_remote_autocommit
- spider_remote_default_database
- spider_remote_sql_log_off
- spider_remote_time_zone
- spider_remote_trx_isolation
- spider_remote_wait_timeout
- spider_reset_sql_alloc
- spider_same_server_link
- spider_second_read
- spider_select_column_mode
- spider_selupd_lock_mode
- spider_semi_split_read
- spider_semi_split_read_limit
- spider_semi_table_lock
- spider_semi_table_lock_connection
- spider_semi_trx
- spider_semi_trx_isolation
- spider_skip_default_condition
- spider_skip_parallel_search
- spider_slave_trx_isolation
- spider_split_read
- spider_store_last_crd
- spider_store_last_sts
- spider_strict_group_by
- spider_sts_bg_mode
- spider_sts_interval
- spider_sts_mode
- spider_sts_sync
- spider_support_xa
- spider_suppress_comment_ignored_warning
- spider_sync_autocommit
- spider_sync_sql_mode
- spider_sync_time_zone
- spider_sync_trx_isolation
- spider_table_crd_thread_count
- spider_table_init_error_interval
- spider_table_sts_thread_count
- spider_udf_ct_bulk_insert_interval
- spider_udf_ct_bulk_insert_rows
- spider_udf_ds_bulk_insert_rows
- spider_udf_ds_table_loop_mode
- spider_udf_ds_use_real_table
- spider_udf_table_lock_mutex_count
- spider_udf_table_mon_mutex_count
- spider_use_all_conns_snapshot
- spider_use_cond_other_than_pk_for_update
- spider_use_consistent_snapshot
- spider_use_default_database
- spider_use_flash_logs
- spider_use_handler
- spider_use_pushdown_udf
- spider_use_snapshot_with_flush_tables
- spider_use_table_charset
- spider_version
- spider_wait_timeout
- spider_xa_register_mode
spider_auto_increment_mode
- Description: The auto increment mode.
-1
Falls back to the default value, if the table parameter is not set.0
Normal Mode. Uses a counter that Spider gets from the remote backend server with an exclusive lock for the auto-increment value. This mode is slow. Use Quick Mode (2
), if you use Spider tables with the table partitioning feature and the auto-increment column is the first column of the index. Before MariaDB 10.3, this value works as "1" for partitioned Spider tables.1
Quick Mode. Uses an internal Spider counter for the auto-increment value. This mode is fast, but it is possible for duplicates to occur when updating the same table from multiple Spider proxies.2
Set Zero Mode. The auto-increment value is given by the remote backend. Sets the column to0
, even if you set the value to the auto-increment column in your statement. If you use the table with the table partitioning feature, it sets to zero after choosing an inserted partition.3
When the auto-increment column is set toNULL
, the value is given by the remote backend server. If you set the auto-increment column to0
,the value is given by the local server. Set spider_reset_auto_incremnet to2
or3
if you want to use an auto-increment column on the remote server.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
0
- Default Table Value:
0
- Range:
-1
to3
- DSN Parameter Name:
aim
spider_bgs_first_read
- Description: Number of first read records to use when performing a concurrent background search. To start a range scan on the remote backend, the storage engine first needs to send the first record. Fetching a second record in the same query can save a network round trip stopping the plan if the backend has a single record. The first and second reads are used to warm up for background search. When not using spider_split_read and spider_semi_split_read, the third read fetches the remaining data source in a single fetch.
-1
Falls back to the default value, if the table parameter is not set.0
Records are usually retrieved.1
and greater: Number of records.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
2
- Default Table Value:
2
- Range:
-1
to9223372036854775807
- DSN Parameter Name:
bfr
spider_bgs_mode
- Description: Background search mode. This enables the use of a thread per data server connection if the query is not shard-based and must be distributed across shards. The partitioning plugin scans partitions one after the other to optimize memory usage. Because the shards are external, reading all shards can be performed in parallel when the plan prunes multiple partitions.
-1
Falls back to the default value, if the table parameter is not set.0
Disables background search.1
Uses background search when searching without locks2
Uses background search when searching without locks or with shared locks.3
Uses background search regardless of locks.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
0
- Default Table Value:
0
- Range:
-1
to3
- DSN Parameter Name:
bmd
spider_bgs_second_read
- Description: Number of second read records on the backend server when using background search. When the first records are found from spider_bgs_first_read, the engine continues scanning a range adding a
LIMIT
of spider_bgs_first_read and spider_bgs_second_read.-1
Falls back to the default value, if the table parameter is not set.0
Records are usually retrieved.1
and greater: Number of records.
- Scope: Global, Session
- Dynamic: Yes
- Default Session Value:
100
- Default Table Value:
100
- Range:
-1
to9223372036854775807
- DSN Parameter Name:
bsr
spider_bka_engine
- Description: Storage engine used with temporary tables when the spider_bka_mode system variable is set to
1
. Defaults to the value of the table parameter, which is MEMORY by default. - Scope: Global, Session
- Dynamic: Yes
- Data Type:
string
- Default Session Value:
""
- Default Table Value:
Memory
- DSN Parameter Name:
bke
spider_bka_mode
- Description: Internal action to perform when multi-split reads are disabled. If the spider_multi_split_read system variable is set to
0
, Spider uses this variable to determine how to handle statements when the optimizer resolves range retrieval to multiple conditions.-1
Falls back to the default value, if the table parameter is not set.0
Uses "union all".1
Uses a temporary table, if it is judged acceptable.2
Uses a temporary table, if it is judged acceptable and avoids replication delay.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
1
- Default Table Value:
1
- Range:
-1
to2
- DSN Parameter Name:
bkm
spider_bka_table_name_type
- Description: The type of temporary table name for bka.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
1
- Range:
-1
to1
spider_block_size
- Description: Size of memory block used in MariaDB. Can usually be left unchanged.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
16384
- Range:
0
to4294967295
- DSN Parameter Name:
bsz
spider_buffer_size
- Description: Buffer size.
-1
, the default, will use the table parameter. - Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
16000
- Default Table Value:
16000
- Range:
-1
to2147483647
- Introduced: MariaDB 10.5.4
spider_bulk_size
- Description: Size in bytes of the buffer when multiple grouping multiple
INSERT
statements in a batch, (that is, bulk inserts).-1
The table parameter is adopted.0
or greater: Size of the buffer.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
16000
- Default Table Value:
16000
- Range:
-1
to2147483647
- DSN Parameter Name:
bsz
spider_bulk_update_mode
- Description: Bulk update and delete mode. Note: If you use a non-default value for the spider_bgs_mode or spider_split_read system variables, Spider sets this variable to
2
.-1
Falls back to the default value, if the table parameter is not set.0
SendsUPDATE
andDELETE
statements one by one.1
Collects multipleUPDATE
andDELETE
statements, then sends the collected statements one by one.2
Collects multipleUPDATE
andDELETE
statements and sends them together.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
0
- Default Table Value:
0
- Range:
-1
to2
- DSN Parameter Name:
bum
spider_bulk_update_size
- Description: Size in bytes for
UPDATE
andDELETE
queries when generating bulk updates.-1
The table parameter is adopted.0
or greater: Size of buffer.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
16000
- Default Table Value:
16000
- Range:
-1
to2147483647
- DSN Parameter Name:
bus
spider_casual_read
- Description: Casual Reads enables all isolation levels, (such as repeatable reads) to work with transactions on multiple backends. With auto-commit queries, you can relax read consistency and run on multiple connections to the backends. This enables parallel queries across partitions, even if multiple shards are stored on the same physical server.
-1
Use table parameter.0
Use casual read.1
Choose connection channel automatically.2
to63
Number of connection channels.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
0
- Default Table Value:
0
- Range:
-1
to63
- DSN Parameter Name:
##
spider_conn_recycle_mode
- Description: Connection recycle mode.
0
Disconnect.1
Recycle by all sessions.2
Recycle in the same session.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Range:
0
to2
- Default Session Value:
0
spider_conn_recycle_strict
- Description: Whether to force the creation of new connections.
1
Don't force.0
Force new connection
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
0
- Range:
0
to1
spider_conn_wait_timeout
- Description: Max waiting time in seconds for Spider to get a remote connection.
- Scope: Global
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
10
- Range:
0
to1000
- Introduced: MariaDB 10.3.3
spider_connect_error_interval
- Description: Return same error code until interval passes if connection is failed
- Scope: Global,
- Dynamic: Yes
- Data Type:
numeric
- Default Value:
1
- Range:
0
to4294967295
spider_connect_mutex
- Description: Whether to serialize remote servers connections (use mutex at connecting). Use this parameter if you get an error or slowdown due to too many connection processes.
0
Not serialized.1
: Serialized.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
boolean
- Default Session Value:
0
spider_connect_retry_count
- Description: Number of times to retry connections that fail due to too many connection processes.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
1000
- Range:
0
to2147483647
spider_connect_retry_interval
- Description: Interval in microseconds for connection failure due to too many connection processes.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
1000
- Range:
-1
to9223372036854775807
spider_connect_timeout
- Description: Timeout in seconds to declare remote backend unresponsive when opening a connection. Change for high-latency networks.
-1
The table parameter is adopted.0
Less than 1.1
and greater: Number of seconds.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
6
- Default Table Value:
0
- Range:
-1
to2147483647
- DSN Parameter Name:
cto
spider_crd_bg_mode
- Description: Indexes cardinality statistics in the background. Disable when the spider_crd_mode system variable is set to
3
or when the spider_crd_interval variable is set to0
.-1
Falls back to the default value, if the table parameter is not set.0
Disables background confirmation.2
Enables background confirmation.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
2
- Default Table Value:
1
- Range:
-1
to2
- DSN Parameter Name:
cbm
spider_crd_interval
- Description: Time interval in seconds of index cardinality statistics. Set to
0
to always get the latest information from remote servers.-1
The table parameter is adopted.1
or more: Interval in seconds table state confirmation.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
51
- Default Table Value:
51
- Range:
-1
to2147483647
- DSN Parameter Name:
civ
spider_crd_mode
- Description: Mode for index cardinality statistics. By default, uses
SHOW
at the table-level.-1,0
Uses the table parameter.1
Uses theSHOW
command.2
Uses the Information Schema.3
Uses theEXPLAIN
command.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
1
- Default Table Value:
1
- Range:
-1
to3
- DSN Parameter Name:
cmd
- Deprecated: MariaDB 10.7.4, MariaDB 10.8.3
spider_crd_sync
- Description: Synchronize index cardinality statistics in partitioned tables.
-1
Falls back to the default value, if the table parameter is not set.0
Disables synchronization.1
Uses table state synchronization when opening a table, but afterwards performs no synchronization.2
Enables synchronization.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
0
- Default Table Value:
0
- Range:
-1
to2
- DSN Parameter Name:
csy
spider_crd_type
- Description: Type of cardinality calculation. Only effective when the spider_crd_mode system variable is set to use
SHOW
(1
) or to use the Information Schema (2
).-1
Falls back to the default value, if the table parameter is not set.0
Uses the value of the spider_crd_weight system variable, as a fixed value.1
Uses the value of the spider_crd_weight system variable, as an addition value.2
Uses the value of the spider_crd_weight system variable, as a multiplication value.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
2
- Default Table Value:
2
- Range:
-1
to2
- DSN Parameter Name:
ctp
- Deprecated: MariaDB 10.7.4, MariaDB 10.8.3
spider_crd_weight
- Description: Weight coefficient used to calculate effectiveness of index from the cardinality of column. For more information, see the description for the spider_crd_type system variable.
-1
Falls back to the default value, if the table parameter is not set.0
or greater: Weight.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
2
- Default Table Value:
2
- Range:
-1
to2147483647
- DSN Parameter Name:
cwg
- Deprecated: MariaDB 10.7.4, MariaDB 10.8.3
spider_delete_all_rows_type
- Description: The type of delete_all_rows.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
1
- Range:
-1
to1
spider_direct_dup_insert
- Description: Manages duplicate key check for REPLACE, INSERT IGNORE and LOAD DATA LOCAL INFILE to remote servers. This can save on network roundtrips if the key always maps to a single partition. For bulk operations, records are checked for duplicate key errors one by one on the remote server, unless you set it to avoid duplicate checks on local servers (
1
).-1
Falls back to the default value, if the table parameter is not set.0
Performs duplicate checks on the local server.1
Avoids duplicate checks on the local server.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
0
- Default Table Value:
0
- Range:
-1
to1
- DSN Parameter Name:
ddi
spider_direct_order_limit
- Description: Pushes
ORDER BY
andLIMIT
operations to the remote server.-1
Falls back to the default value, if the table parameter is not set.0
Uses local execution.1
Uses push down execution.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
2
- Default Table Value:
9223372036854775807
- Range:
-1
to9223372036854775807
- DSN Parameter Name:
dol
spider_disable_group_by_handler
- Description: Whether to disable the spider group by handler, which if created takes over the query execution after query optimization is done.
OFF
Does not disable the spider group by handler.ON
Disables the spider group by handler.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
boolean
- Default Value:
OFF
- Introduced: MariaDB 10.10.7
spider_dry_access
- Description: Simulates an empty result-set. No queries are sent to the backend. Use for performance tuning.
0
Normal access.1
All access from Spider to data node is suppressed.
- Scope: Global
- Dynamic: No
- Data Type:
boolean
- Default Value:
OFF
spider_error_read_mode
- Description: Sends an empty result-set when reading a backend server raises an error. Useful with applications that don't implement transaction replays.
-1
Falls back to the default value, if the table parameter is not set.0
Returns an error.1
Returns an empty result.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
0
- Default Table Value:
0
- Range:
-1
to1
- DSN Parameter Name:
erm
spider_error_write_mode
- Description: Sends an empty result-set when writing to a backend server raises an error. Useful with applications that don't implement transaction replays.
-1
Falls back to the default value, if the table parameter is not set.0
Returns an error.1
Returns an empty result-set on error.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
0
- Default Table Value:
0
- Range:
-1
to1
- DSN Parameter Name:
ewm
spider_first_read
- Description: Number of first read records to start a range scan on the backend server. Spider needs to send the first record. Fetching the second record saves network round-trips, stopping the plan if the backend has a single record. First read and second read are used to warm up for background searches, third reads without using the spider_split_read and spider_semi_split_read system variables fetches the remaining data source in a single last fetch.
-1
Use the table parameter.0
Usually retrieves records.1
and greater: Sets the number of first read records.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
0
- Default Table Value:
2
- Range:
-1
to9223372036854775807
- DSN Parameter Name:
frd
spider_force_commit
- Description: Behavior when error occurs on
XA PREPARE
,XA COMMIT
, andXA ROLLBACK
statements.0
Returns the error.1
Returns the error when thexid
doesn't exist, otherwise it continues processing the XA transaction.2
Continues processing the XA transaction, disregarding all errors.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
0
- Range:
0
to2
spider_general_log
- Description: Whether Spider logs all commands to the General Log. Spider logs error codes according to the spider_log_result_errors system variable.
OFF
Logs no commands.ON
Logs commands to the General Log.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
boolean
- Default Session Value:
OFF
spider_ignore_comments
- Description: Whether to unconditionally ignore COMMENT and CONNECTION strings without checking whether table options are specified.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
boolean
- Default Value:
OFF
- Introduced: MariaDB 11.3.0
spider_index_hint_pushdown
- Description: Whether to use pushdown index hints, like
force_index
.0
Do not use pushdown hints1
Use pushdown hints
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
boolean
- Default Session Value:
OFF
- Introduced: MariaDB 10.3.3
spider_init_sql_alloc_size
- Description: Initial size of the local SQL buffer.
-1
Falls back to the default value, if the table parameter is not set.0
or greater: Size of the buffer.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
1024
- Default Table Value:
1024
- DSN Parameter Name:
isa
- Range:
-1
to2147483647
- Deprecated: MariaDB 10.7.5, MariaDB 10.8.4, MariaDB 10.9.2
spider_internal_limit
- Description: Limits the number of records when acquired from a remote server.
-1
The table parameter is adopted.0
or greater: Records limit.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
9223372036854775807
- Default Table Value:
9223372036854775807
- Range:
-1
to9223372036854775807
- DSN Parameter Name:
ilm
- Deprecated: MariaDB 10.7.4, MariaDB 10.8.3
spider_internal_offset
- Description: Skip records when acquired from the remote server.
-1
Falls back to the default value, if the table parameter is not set.0
or more : Number of records to skip.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
0
- Default Table Value:
0
- Range:
-1
to9223372036854775807
- DSN Parameter Name:
ios
- Deprecated: MariaDB 10.7.4, MariaDB 10.8.3
spider_internal_optimize
- Description: Whether to perform push down operations for OPTIMIZE TABLE statements.
-1
Falls back to the default value, if the table parameter is not set.0
Transmitted.1
Not transmitted.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
0
- Default Table Value:
0
- Range:
-1
to1
- DSN Parameter Name:
iom
spider_internal_optimize_local
- Description: Whether to transmit to remote servers when OPTIMIZE TABLE statements are executed on the local server.
-1
Falls back to the default value, if the table parameter is not set.0
Not transmitted.1
Transmitted.
- Default Session Value:
0
- Default Table Value:
0
- Range:
-1
to1
- DSN Parameter Name:
iol
spider_internal_sql_log_off
- Description: Whether to log SQL statements sent to the remote server in the General Query Log.
- Explicitly setting this system variable to either
ON
orOFF
causes the Spider node to send aSET sql_log_off
statement to each of the data nodes using theSUPER
privilege. -1
Don't know or does not matter; don't send 'SET SQL_LOG_OFF' statement0
Send 'SET SQL_LOG_OFF 0' statement to data nodes (logs SQL statements to the remote server)1
Send 'SET SQL_LOG_OFF 1' statement to data nodes (doesn't log SQL statements to the remote server)
- Explicitly setting this system variable to either
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
(previouslyboolean
) - Range:
-1
to1
- Default Session Value:
-1
(previouslyON
)
spider_internal_unlock
- Description: Whether to transmit unlock tables to the connection of the table used with
SELECT
statements.0
Not transmitted.1
Transmitted.
- Data Type:
boolean
- Default Session Value:
0
spider_internal_xa
- Description: Whether to implement XA at the server- or storage engine-level. When using the server-level, set different values for the server_id system variable on all server instances to generate different
xid
values.OFF
Uses the storage engine protocol.ON
Uses the server protocol.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
boolean
- Default Session Value:
OFF
spider_internal_xa_id_type
- Description: The type of internal_xa id.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
0
- Range:
-1
to1
spider_internal_xa_snapshot
- Description: Limitation for reading consistent data on all backend servers when using MariaDB's internal XA implementation and
START TRANSACTION WITH CONSISTENT SNAPSHOT
.0
Raise error when using a Spider table.1
Raise error when issued aSTART TRANSACTION
statement.2
Takes a consistent snapshot on each backend, but loses global consistency.3
Starts transactions with XA, but removesCONSISTENT SNAPSHOT
.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Range:
0
to3
- Default Session Value:
0
spider_load_crd_at_startup
- Description: Whether to load CRD from the system table at startup.
-1
Use table parameter0
Do not load1
Load
- Scope: Global
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
1
- Range:
-1
to1
- Introduced: MariaDB 10.3.3
- Deprecated: MariaDB 10.7.4, MariaDB 10.8.3
spider_load_sts_at_startup
- Description: Whether to load STS from the system table at startup.
-1
Use table parameter0
Do not load1
Load
- Scope: Global
- Dynamic: Yes
- Data Type:
boolean
- Default Session Value:
1
- Range:
-1
to1
- Introduced: MariaDB 10.3.3
- Deprecated: MariaDB 10.7.4, MariaDB 10.8.3
spider_local_lock_table
- Description: Whether to push LOCK TABLES statements down to the remote server.
0
Transmitted.1
Not transmitted.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
boolean
- Default Value:
0
spider_lock_exchange
- Description:
Whether to convert SELECT... LOCK IN SHARE MODE and SELECT... FOR UPDATE statements into a LOCK TABLE statement.
0
Not converted.1
Converted.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
boolean
- Default Value:
0
spider_log_result_error_with_sql
- Description: How to log SQL statements with result errors.
0
No log1
Log error2
Log warning summary3
Log warning4
Log info (Added in MariaDB 10.5.4)
- Scope: Global
- Dynamic: Yes
- Data Type:
numeric
- Default Value:
0
- Range:
0
to4
spider_log_result_errors
- Description: Log results from data nodes to the Spider node in the Error Log. Performs no logging by default.
0
: Logs no errors from data nodes.1
: Logs errors from data nodes.2
: Logs errors from data nodes, as well as warning summaries.3
: Logs errors from data nodes, as well as warning summaries and details.4
: Logs errors from data nodes, as well as warning summaries and details, and result summaries.
- Scope: Global
- Dynamic: Yes
- Data Type:
numeric
- Default Value:
0
- Range:
0
to4
spider_low_mem_read
- Description: Whether to use low memory mode when executing queries issued internally to remote servers that return result-sets.
-1
Falls back to the default value, if the table parameter is not set.0
Doesn't use low memory mode.1
Uses low memory mode.
- Data Type:
numeric
- Default Session Value:
1
- Default Table Value:
1
- Range:
-1
to1
spider_max_connections
- Description: Maximum number of connections from Spider to a remote MariaDB servers. Defaults to
0
, which is no limit. - Command-line:
--spider-max-connections
- Scope: Global
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
0
- Range:
0
to99999
- Introduced: MariaDB 10.3.3
spider_max_order
- Description: Maximum number of columns for
ORDER BY
operations.-1
The table parameter is adopted.0
and greater: Maximum number of columns.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
32767
- Default Table Value:
32767
- Range:
-1
to32767
- DSN Parameter Name:
mod
spider_multi_split_read
- Description:
Whether to divide a statement into multiple SQL statements sent to the remote backend server when the optimizer resolves range retrievals to multiple conditions.
-1
Falls back to the default value, if the table parameter is not set.0
Doesn't divide statements.1
Divides statements.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
100
- Default Table Value:
100
- Range:
-1
to2147483647
- DSN Parameter Name:
msr
spider_net_read_timeout
- Description: TCP timeout in seconds to declare remote backend servers unresponsive when reading from a connection. Change for high latency networks.
-1
Falls back to the default value, if the table parameter is not set.0
Less than 1 second timeout.1
and greater: Timeout in seconds.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
600
- Default Table Value:
600
- Range:
-1
to2147483647
- DSN Parameter Name:
nrt
spider_net_write_timeout
- Description: TCP timeout in seconds to declare remote backend servers unresponsive when writing to a connection. Change for high latency networks.
-1
The table parameter is adopted.0
Less than 1 second timeout.1
and more: Timeout in seconds.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
600
- Default Table Value:
600
- Range:
-1
to2147483647
- DSN Parameter Name:
nwt
spider_ping_interval_at_trx_start
- Description: Resets the connection with keepalive timeout in seconds by sending a ping.
0
At every transaction.1
and greater: Number of seconds.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Value:
3600
- Range:
0
to2147483647
spider_quick_mode
- Description: Sets the backend query buffering to cache on the remote backend server or in the local buffer.
-1
Falls back to the default value, if the table parameter is not set.0
Local buffering, it acquires records collectively withstore_result
.1
Remote buffering, it acquires records one by one. Interrupts don't wait and recovery on context switch back.2
Remote buffering, it acquires records one by one. Interrupts wait to the end of the acquisition.3
Local buffering, uses a temporary table on disk when the result-set is greater than the value of the spider_quick_page_size system variable.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
3
- Default Table Value:
3
- Range:
-1
to3
- DSN Parameter Name:
qmd
spider_quick_page_byte
- Description: Memory limit by size in bytes in a page when acquired record by record.
-1
The table parameter is used. When quick_mode is 1 or 2, Spider stores at least 1 record even if quick_page_byte is smaller than 1 record. When quick_mode is 3, quick_page_byte is used for judging using temporary tables. That is given priority when spider_quick_page_byte is set.0
or greater: Memory limit.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
10485760
- Range:
-1
to9223372036854775807
- Introduced: MariaDB 10.4.3, MariaDB 10.3.13
spider_quick_page_size
- Description: Number of records in a page when acquired record by record.
-1
The table parameter is adopted.0
or greater: Number of records.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
1024
(>=MariaDB 10.7),-1
(<= MariaDB 10.6) - Default Table Value:
100
- Range:
-1
to9223372036854775807
- DSN Parameter Name:
qps
spider_read_only_mode
- Description: Whether to allow writes on Spider tables.
-1
Falls back to the default value, if the table parameter is not set.0
Allows writes to Spider tables.1
Makes tables read- only.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
0
(>=MariaDB 10.7),-1
(<= MariaDB 10.6) - Default Table Value:
0
- Range:
-1
to1
- DSN Parameter Name:
rom
spider_remote_access_charset
- Description: Forces the specified session character set when connecting to the backend server. This can improve connection time performance.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
string
- Default Session Value:
null
spider_remote_autocommit
- Description: Sets the auto-commit mode when connecting to backend servers. This can improve connection time performance.
-1
Doesn't change the auto-commit mode.0
Sets the auto-commit mode to0
.1
Sets the auto-commit mode to1
.
- Scope: Global
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
-1
- Range:
-1
to1
spider_remote_default_database
- Description: Sets the local default database when connecting to backend servers. This can improve connection time performance.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
string
- Default Session Value: Empty string
spider_remote_sql_log_off
- Description: Sets the sql_log_off system variable to use when connecting to backend servers.
-1
Doesn't set the value.0
Doesn't log Spider SQL statements to remote backend servers.1
Logs SQL statements on remote backend
- Scope: Global
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
-1
- Range:
-1
to1
spider_remote_time_zone
- Description: Forces the specified time zone setting when connecting to backend servers. This can improve connection performance when you know the time zone.
- Scope: Global
- Dynamic: Yes
- Data Type:
string
- Default Session Value:
null
spider_remote_trx_isolation
- Description: Sets the Transaction Isolation Level when connecting to the backend server.
-1
Doesn't set the Isolation Level.0
Sets to theREAD UNCOMMITTED
level.1
Sets to theREAD COMMITTED
level.2
Sets to theREPEATABLE READ
level.3
Sets to theSERIALIZABLE
level.
- Scope: Global
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
-1
- Range:
-1
to3
spider_remote_wait_timeout
- Description: Wait timeout in seconds on remote server.
-1
means not set. - Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Value:
-1
- Range:
-1
to2147483647
- Introduced: MariaDB 10.4.5
spider_reset_sql_alloc
- Description: Resets the per connection SQL buffer after an SQL statement executes.
-1
Falls back to the default value, if the table parameter is not set.0
Doesn't reset.1
Resets.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
1
- Default Table Value:
1
- Range:
-1
to1
- DSN Parameter Name:
rsa
spider_same_server_link
- Description: Enables the linking of a table to the same local instance.
0
Disables linking.1
Enables linking.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
boolean
- Default Session Value:
OFF
spider_second_read
- Description: Number of second read records on the backend server when the first records are found from the first read. Spider continues scanning a range, adding a
LIMIT
using the spider_first_read and spider_second_read variables.-1
Falls back to the default value, if the table parameter is not set.0
Usually retrieves records.1
and greater: Number of records.
- Scope: Global, Session
- Dynamic: Yes
- Default Session Value:
0
- Default Table Value:
0
- Range:
-1
to9223372036854775807
- DSN Parameter Name:
srd
spider_select_column_mode
- Description: Mode for column retrieval from remote backend server.
-1
Falls back to the default value, if the table parameter is not set.0
Uses index columns when theSELECT
statement can resolve with an index, otherwise uses all columns.1
Uses all columns judged necessary to resolve the query.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
1
- Default Table Value:
1
- Range:
-1
to1
- DSN Parameter Name:
scm
spider_selupd_lock_mode
- Description: Local lock mode on
INSERT SELECT
.-1
Falls back to the default value, if the table parameter is not set.0
Takes no locks.1
Takes shared locks.2
Takes exclusive locks.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
1
- Default Table Value:
1
- Range:
-1
to2
- DSN Parameter Name:
slm#
spider_semi_split_read
- Description:
Whether to use chunk retrieval with offset and limit parameters on SQL statements sent to the remote backend server when using the spider_split_read system variable.
-1
Falls back to the default value, if the table parameter is not set.0
Doesn't use chunk retrieval.1 or more
Uses chunk retrieval.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
2
- Default Table Value:
2
- Range:
-1
to2147483647
- DSN Parameter Name:
ssr#
spider_semi_split_read_limit
- Description: Sets the limit value for the spider_semi_split_read system variable.
-1
Falls back to the default value, if the table parameter is not set.0
or more: The limit value.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
9223372036854775807
- Default Table Value:
9223372036854775807
- Range:
-1
to9223372036854775807
- DSN Parameter Name:
ssl#
spider_semi_table_lock
- Description: Enables semi-table locking. This adds a LOCK TABLES statement to SQL executions sent to the remote backend server when using non-transactional storage engines to preserve consistency between roundtrips.
0
Disables semi-table locking.1
Enables semi-table locking.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
0
(>=MariaDB 10.8),1
(<= MariaDB 10.7) - Range:
0
to1
- DSN Parameter Name:
stl#
spider_semi_table_lock_connection
- Description: Whether to use multiple connections with semi-table locking. To enable semi-table locking, use the spider_semi_table_lock system variable.
-1
Falls back to the default value, if the table parameter is not set.0
Uses the same connection.1
Uses different connections.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
1
- Default Table Value:
1
- Range:
-1
to1
- DSN Parameter Name:
stc#
spider_semi_trx
- Description: Enables semi-transactions. This controls transaction consistency when an SQL statement is split into multiple statements issued to the backend servers. You can preserve or relax consistency as need. Spider encapsulates auto-committed SQL statements within a transaction on the remote backend server. When using
READ COMMITTED
orREAD UNCOMMITTED
transaction isolation levels to force consistency, set the spider_semi_trx_isolation system variable to2
.0
Disables semi-transaction consistency.1
Enables semi-transaction consistency.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
boolean
- Default Session Value:
ON
spider_semi_trx_isolation
- Description: Set consistency during range SQL execution when spider_sync_trx_isolation is 1
-1
OFF0
READ UNCOMMITTED1
READ COMMITTED2
REPEATABLE READ3
SERIALIZABLE
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
-1
- Range:
-1
to3
spider_skip_default_condition
- Description: Whether to compute condition push downs.
-1
Falls back to the default value, if the table parameter is not set.0
Computes condition push downs.1
Doesn't compute condition push downs.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
0
- Default Table Value:
0
- Range:
-1
to1
- DSN Parameter Name:
sdc
spider_skip_parallel_search
- Description: Whether to skip parallel search by specific conditions.
-1
:use table parameter0
:not skip1
:skip parallel search if query is not SELECT statement2
:skip parallel search if query has SQL_NO_CACHE3
:1+2
- Commandline:
--spider-skip-parallel-search=#
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
0
- Range:
-1
to3
- Introduced: MariaDB 10.3.3
spider_slave_trx_isolation
- Description: Transaction isolation level when Spider table is used by slave SQL thread.
-1
off0
read uncommitted1
read committed2
repeatable read3
serializable
- Commandline:
--spider-slave-trx-isolation=#
- Scope: Global
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
-1
- Range:
-1
to3
- Introduced: MariaDB 10.4.3, MariaDB 10.3.13
spider_split_read
- Description: Number of records in chunk to retry the result when a range query is sent to remote backend servers.
-1
Falls back to the default value, if the table parameter is not set.0
or more: Number of records.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
9223372036854775807
- Default Table Value:
9223372036854775807
- Range:
-1
to9223372036854775807
- DSN Parameter Name:
srd
spider_store_last_crd
- Description: Whether to store last CRD result in the system table.
-1
Use table parameter.0
Do not store last CRD result in the system table.1
Store last CRD result in the system table.
- Commandline:
--spider-store-last-crd=#
- Scope: Global
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
1
- Range:
-1
to1
- Introduced: MariaDB 10.3.3
- Deprecated: MariaDB 10.7.4, MariaDB 10.8.3
spider_store_last_sts
- Description: Whether to store last STS result in the system table.
-1
Use table parameter.0
Do not store last STS result in the system table.1
Store last STS result in the system table.
- Commandline:
--spider-store-last-sts=#
- Scope: Global
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
1
- Range:
-1
to1
- Introduced: MariaDB 10.3.3
- Deprecated: MariaDB 10.7.4, MariaDB 10.8.3
spider_strict_group_by
- Description:
Whether to use columns in select clause strictly for group by clause
-1
Use the table parameter.0
Do not strictly use columns in select clause for group by clause1
Use columns in select clause strictly for group by clause
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
1
- Range:
-1
to1
- Introduced: MariaDB 10.5.4
spider_sts_bg_mode
- Description:
Enables background confirmation for table statistics. When background confirmation is enabled, Spider uses one thread per partition to maintain table status. Disable when the spider_sts_interval system variable is set to
0
, which causes Spider to always retrieve the latest information as need. It is effective, when the spider_sts_interval system variable is set to10
.-1
Falls back to the default value, if the table parameter is not set.0
Disables background confirmation.1
Enables background confirmation (create thread per table/partition).2
Enables background confirmation (use static threads). (from MariaDB 10.)
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
2
- Range:
-1
to2
- DSN Parameter Name:
sbm
spider_sts_interval
- Description: Time interval of table statistics from the remote backend servers.
-1
Falls back to the default value, if the table parameter is not set.0
Retrieves the latest table statistics on request.1
or more: Interval in seconds for table state confirmation.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
10
- Default Table Value:
10
- Range:
-1
to2147483647
- DSN Parameter Name:
siv
spider_sts_mode
- Description: Table statistics mode.
Mode for table statistics. The SHOW command is used at the table level default.
-1,0
Uses the table parameter.1
Uses theSHOW
command.2
Uses the Information Schema.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
1
- Default Table Value:
1
- Range:
-1
to2
- DSN Parameter Name:
smd
- Deprecated: MariaDB 10.7.4, MariaDB 10.8.3
spider_sts_sync
- Description: Synchronizes table statistics in partitioned tables.
-1
Falls back to the default value, if the table parameter is not set.0
Doesn't synchronize table statistics in partitioned tables.1
Synchronizes table state when opening a table, doesn't synchronize after opening.2
Synchronizes table statistics.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Session Value:
0
- Default Table Value:
0
- Range:
-1
to2
- DSN Parameter Name:
ssy
spider_support_xa
- Description: XA Protocol for mirroring and for multi-shard transactions.
1
Enables XA Protocol for these Spider operations.0
Disables XA Protocol for these Spider operations.
- Scope: Global
- Dynamic: No
- Data Type:
boolean
- Default Table Value:
1
spider_suppress_comment_ignored_warning
- Description: Whether to suppress warnings that table COMMENT or CONNECTION strings are ignored due to specified table options.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
boolean
- Default Value:
OFF
- Introduced: MariaDB 11.3.0
spider_sync_autocommit
- Description: Whether to push down local auto-commits to remote backend servers.
OFF
Pushes down local auto-commits.ON
Doesn't push down local auto-commits.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
boolean
- Default Session Value:
ON
spider_sync_sql_mode
- Description: Whether to sync sql_mode.
OFF
No syncON
Sync
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
boolean
- Default Value:
ON
- Introduced: MariaDB 10.4.7
spider_sync_time_zone
- Description: Whether to push the local time zone down to remote backend servers.
OFF
Doesn't synchronize time zones.ON
Synchronize time zones.
- Scope: Global
- Dynamic: Yes
- Data Type:
boolean
- Default Session Value:
OFF
- Removed: MariaDB 10.3.9
spider_sync_trx_isolation
- Description: Pushes local transaction isolation levels down to remote backend servers.
OFF
Doesn't push down local isolation levels.ON
Pushes down local isolation levels.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
boolean
- Default Session Value:
ON
spider_table_crd_thread_count
- Description: Static thread count of table crd.
- Commandline:
--spider-table-crd-thread-count=#
- Scope: Global
- Dynamic: No
- Data Type:
numeric
- Default Value:
10
- Range:
1
to4294967295
- Introduced: MariaDB 10.3.3
spider_table_init_error_interval
- Description: Interval in seconds where the same error code is returned if table initialization fails. Use to protect against infinite loops in table links.
- Scope: Global
- Dynamic: Yes
- Data Type:
numeric
- Default Value:
1
- Range:
0
to4294967295
spider_table_sts_thread_count
- Description: Static thread count of table sts.
- Commandline:
--spider-table-sts-thread-count=#
- Scope: Global
- Dynamic: No
- Data Type:
numeric
- Default Value:
10
- Range:
1
to4294967295
- Introduced: MariaDB 10.3.3
spider_udf_ct_bulk_insert_interval
- Description: Interval in milliseconds between bulk inserts at copying. For use with the UDF spider_copy_tables, which copies table data linked to a Spider table from the source server to destination server using bulk insert. If this interval is 0, it may cause higher write traffic.
-1
Uses the UDF parameter.0
and more: Time in milliseconds.
- Scope: Global
- Dynamic: Yes
- Data Type:
numeric
- Default Value:
10
- Default Table Value:
10
- Range:
-1
to2147483647
- Deprecated: MariaDB 10.7.4, MariaDB 10.8.3
- Removed: MariaDB 10.10
spider_udf_ct_bulk_insert_rows
- Description: Number of rows to insert at a time when copying during bulk inserts.
-1, 0
: Uses the table parameter.1
and more: Number of rows
- Scope: Global
- Dynamic: Yes
- Data Type:
numeric
- Default Value:
100
- Default Table Value:
100
- Range:
-1
to9223372036854775807
- Deprecated: MariaDB 10.7.4, MariaDB 10.8.3
- Removed: MariaDB 10.10
spider_udf_ds_bulk_insert_rows
- Description: Number of rows inserted at a time during bulk inserts when the result-set is stored in a temporary table on executing a UDF.
-1, 0
Uses the UDF parameter.1
or more: Number of rows
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Value:
3000
- Default Table Value:
3000
- Range:
-1
to9223372036854775807
- Deprecated: MariaDB 10.7.4, MariaDB 10.8.3
- Removed: MariaDB 10.10
spider_udf_ds_table_loop_mode
- Description: Whether to store the result-set in the same temporary table when the temporary table list count for UDF is less than the result-set count on UDF execution.
-1
Falls back to the default value, if the table parameter is not set.0
Drops records.1
Inserts the last table.2
Inserts the first table and loops again.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Value:
0
- Range:
-1
to2
- Deprecated: MariaDB 10.7.4, MariaDB 10.8.3
- Removed: MariaDB 10.10
spider_udf_ds_use_real_table
- Description: Whether to use real table for temporary table list.
-1
Use UDF parameter.0
Do not use real table.1
Use real table.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Value:
0
- Range:
-1
to1
- Deprecated: MariaDB 10.7.4, MariaDB 10.8.3
- Removed: MariaDB 10.10
spider_udf_table_lock_mutex_count
- Description: Mutex count of table lock for Spider UDFs.
- Scope: Global
- Dynamic: No
- Data Type:
numeric
- Default Value:
20
- Range:
1
to4294967295
- Removed: MariaDB 10.10
spider_udf_table_mon_mutex_count
- Description: Mutex count of table mon for Spider UDFs.
- Scope: Global
- Dynamic: No
- Data Type:
numeric
- Default Value:
20
- Range:
1
to4294967295
- Removed: MariaDB 10.10
spider_use_all_conns_snapshot
- Description: Whether to pass
START TRANSACTION WITH SNAPSHOT
statements to all connections.OFF
Doesn't pass statement to all connections.ON
Passes statement to all connections.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
boolean
- Default Session Value:
OFF
spider_use_cond_other_than_pk_for_update
- Description: Whether to use all conditions even if condition has a primary key.
0
Don't use all conditions1
Use all conditions
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Value:
1
- Range:
0
to1
- Introduced: MariaDB 10.3.13, MariaDB 10.4.3
spider_use_consistent_snapshot
- Description:
Whether to push a local
START TRANSACTION WITH CONSISTENT
statement down to remote backend servers.OFF
Doesn't push the local statement down.ON
Pushes the local statement down.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
boolean
- Default Value:
OFF
spider_use_default_database
- Description: Whether to use the default database.
OFF
Doesn't use the default database.ON
Uses the default database.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
boolean
- Default Value:
ON
spider_use_flash_logs
- Description: Whether to push FLUSH LOGS statements down to remote backend servers.
OFF
Doesn't push the statement down.ON
Pushes the statement down.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
boolean
- Default Value:
OFF
spider_use_handler
- Description: Converts HANDLER SQL statements.
When the spider_sync_trx_isolation system variable is set to
0
, Spider disables HANDLER conversions to prevent use of the statement on the SERIALIZABLE isolation level.-1
Falls back to the default value, if the table parameter is not set.0
Converts HANDLER statements into SELECT statements.1
Passes HANDLER to the remote backend server.2
Converts SQL statements to HANDLER statements.3
Converts SQL statements to HANDLER statements and HANDLER statements to SQL statements.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Value:
0
- Default Table Value:
0
- Range:
-1
to3
- DSN Parameter Name:
uhd
- Deprecated: MariaDB 10.7.4, MariaDB 10.8.3
- Removed: MariaDB 10.10
spider_use_pushdown_udf
- Description:
When using a UDF function in a condition and the engine_condition_pushdown system variable is set to
1
, whether to execute the UDF function locally or push it down.-1
Falls back to the default value, if the table parameter is not set.0
Doesn't transmit the UDF1
Transmits the UDF.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Value:
-1
- Default Table Value:
1
- Range:
-1
to1
- DSN Parameter Name:
upu
spider_use_snapshot_with_flush_tables
- Description:
Whether to encapsulate FLUSH LOGS and UNLOCK TABLES statements when
START TRANSACTION WITH CONSISTENT
andFLUSH TABLE WITH READ LOCK
statements are sent to the remote backend servers.0
: No encapsulation.1
: Encapsulates, only when the spider_use_all_conns_snapshot system variable i set to1
.2
: Synchronizes the snapshot using a LOCK TABLES statement and [flush|FLUSH TABLES]] at the XA transaction level. This is only effective when the spider_use_all_cons_snapshot system variable is set to1
.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Value:
0
- Range:
0
to2
spider_use_table_charset
- Description: Whether to use the local table character set for the remote backend server connections.
-1
Falls back to the default value, if the table parameter is not set.0
Useutf8
.1
Uses the table character set.
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Value:
1
- Default Table Value:
1
- Range:
-1
to1
- DSN Parameter Name:
utc
spider_version
- Description: The current Spider version. Removed in MariaDB 10.9.2 when the Spider version number was matched with the server version.
- Scope: Global
- Dynamic: No
- Data Type:
string
- Removed: MariaDB 10.9.2
spider_wait_timeout
- Description: Wait timeout in seconds of setting to remote server.
-1
means not set. - Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Value:
604800
- Range:
-1
to2147483647
- Introduced: MariaDB 10.4.5
spider_xa_register_mode
- Description: Mode of XA transaction register into system table.
0
Register all XA transactions1
Register only write XA transactions
- Command-line:
--spider-xa-register-mode=#
- Scope: Global, Session
- Dynamic: Yes
- Data Type:
numeric
- Default Value:
1
- Range:
0
to1
- Introduced: MariaDB 10.3.3
- Deprecated: MariaDB 10.7.4, MariaDB 10.8.3