Federated Queries #
| Syntax | Description | Type |
|---|---|---|
| ALTER SQL_FEDERATION RULE( SQL_FEDERATION_ENABLED=true/false, EXECUTION_PLAN_CACHE(INITIAL_CAPACITY=2000, MAXIMUM_SIZE=65535), MAX_USAGE_MEMORY_PER_QUERY=‘50M’, SPILL_ENABLED=true/false, SPILL_PATH=“path”, SPILL_COMPRESSION_ENABLED=true/false ); | RAL | |
| SHOW SQL_FEDERATION RULE | Query federated query rule configuration | RQL |
1. Update Federated Query Rule Configuration #
ALTER SQL_FEDERATION RULE( SQL_FEDERATION_ENABLED=true/false, EXECUTION_PLAN_CACHE(INITIAL_CAPACITY=xxx, MAXIMUM_SIZE=xxxx)MAX_USAGE_MEMORY_PER_QUERY='xxx', SPILL_ENABLED=false, SPILL_PATH="xxx", SPILL_COMPRESSION_ENABLED=false);
Parameter Explanation
SQL_FEDERATION_ENABLED: Federated query switch EXECUTION_PLAN_CACHE: Execution plan cache INITIAL_CAPACITY: Initial cache size MAXIMUM_SIZE: Maximum cache size MAX_USAGE_MEMORY_PER_QUERY: Maximum available memory per query SPILL_ENABLED: Whether spilling is allowed SPILL_PATH: Spill path SPILL_COMPRESSION_ENABLED: Spill encryption
Example
ALTER SQL_FEDERATION RULE(
SQL_FEDERATION_ENABLED=false,
EXECUTION_PLAN_CACHE(INITIAL_CAPACITY=2000, MAXIMUM_SIZE=65535),
MAX_USAGE_MEMORY_PER_QUERY='50M',
SPILL_ENABLED=false,
SPILL_PATH="path",
SPILL_COMPRESSION_ENABLED=false
);
- Query Federated Query Rule Configuration
SHOW SQL_PARSER RULE
Parameter Explanation
None
Example
SHOW SQL_PARSER RULE;
+------------------------+-------------------------------------------+----------------------------+---------------+------------+---------------------------+
| sql_federation_enabled | execution_plan_cache | max_usage_memory_per_query | spill_enabled | spill_path | spill_compression_enabled |
+------------------------+-------------------------------------------+----------------------------+---------------+------------+---------------------------+
| false | initialCapacity: 2000, maximumSize: 65535 | 50M | false | path | false |
+------------------------+-------------------------------------------+----------------------------+---------------+------------+---------------------------+