system.settings
Stores the system settings of the current session.
SELECT * FROM system.settings;
---
name |value |default |level |description |type |
-------------------------------------+------------+------------+-------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------+
collation |binary |binary |SESSION|Sets the character collation. Available values include "binary" and "utf8". |String|
enable_bushy_join |0 |0 |SESSION|Enables generating a bushy join plan with the optimizer. |UInt64|
enable_cbo |1 |1 |SESSION|Enables cost-based optimization. |UInt64|
enable_distributed_eval_index |1 |1 |SESSION|Enables evaluated indexes to be created and maintained across multiple nodes. |UInt64|
enable_dphyp |0 |0 |SESSION|Enables dphyp join order algorithm. |UInt64|
enable_query_result_cache |0 |0 |SESSION|Enables caching query results to improve performance for identical queries. |UInt64|
enable_runtime_filter |0 |0 |SESSION|Enables runtime filter optimization for JOIN. |UInt64|
flight_client_timeout |60 |60 |SESSION|Sets the maximum time in seconds that a flight client request can be processed. |UInt64|
group_by_shuffle_mode |before_merge|before_merge|SESSION|Group by shuffle mode, 'before_partial' is more balanced, but more data needs to exchange. |String|
group_by_two_level_threshold |20000 |20000 |SESSION|Sets the number of keys in a GROUP BY operation that will trigger a two-level aggregation. |UInt64|
hide_options_in_show_create_table |1 |1 |SESSION|Hides table-relevant information, such as SNAPSHOT_LOCATION and STORAGE_FORMAT, at the end of the result of SHOW TABLE CREATE. |UInt64|
input_read_buffer_size |1048576 |1048576 |SESSION|Sets the memory size in bytes allocated to the buffer used by the buffered reader to read data from storage. |UInt64|
load_file_metadata_expire_hours |168 |168 |SESSION|Sets the hours that the metadata of files you load data from with COPY INTO will expire in. |UInt64|
max_block_size |65536 |65536 |SESSION|Sets the maximum byte size of a single data block that can be read. |UInt64|
max_execute_time |0 |0 |SESSION|Sets the maximum query execution time in seconds. Setting it to 0 means no limit. |UInt64|
max_inlist_to_or |3 |3 |SESSION|Sets the maximum number of values that can be included in an IN expression to be converted to an OR operator. |UInt64|
max_memory_usage |6871947673 |6871947673 |SESSION|Sets the maximum memory usage in bytes for processing a single query. |UInt64|
max_result_rows |0 |0 |SESSION|Sets the maximum number of rows that can be returned in a query result when no specific row count is specified. Setting it to 0 means no limit. |UInt64|
max_storage_io_requests |48 |48 |SESSION|Sets the maximum number of concurrent I/O requests. |UInt64|
max_threads |8 |8 |SESSION|Sets the maximum number of threads to execute a request. |UInt64|
parquet_uncompressed_buffer_size |2097152 |2097152 |SESSION|Sets the byte size of the buffer used for reading Parquet files. |UInt64|
prefer_broadcast_join |1 |1 |SESSION|Enables broadcast join. |UInt64|
query_result_cache_allow_inconsistent|0 |0 |SESSION|Determines whether Databend will return cached query results that are inconsistent with the underlying data. |UInt64|
query_result_cache_max_bytes |1048576 |1048576 |SESSION|Sets the maximum byte size of cache for a single query result. |UInt64|
query_result_cache_ttl_secs |300 |300 |SESSION|Sets the time-to-live (TTL) in seconds for cached query results. Once the TTL for a cached result has expired, the result is considered stale and will not be used for new queries.|UInt64|
quoted_ident_case_sensitive |1 |1 |SESSION|Determines whether Databend treats quoted identifiers as case-sensitive. |UInt64|
retention_period |12 |12 |SESSION|Sets the retention period in hours. |UInt64|
sandbox_tenant | | |SESSION|Injects a custom 'sandbox_tenant' into this session. This is only for testing purposes and will take effect only when 'internal_enable_sandbox_tenant' is turned on. |String|
spilling_bytes_threshold_per_proc |0 |0 |SESSION|Sets the maximum amount of memory in bytes that an aggregator can use before spilling data to storage during query execution. |UInt64|
sql_dialect |PostgreSQL |PostgreSQL |SESSION|Sets the SQL dialect. Available values include "PostgreSQL", "MySQL", and "Hive". |String|
storage_fetch_part_num |2 |2 |SESSION|Sets the number of partitions that are fetched in parallel from storage during query execution. |UInt64|
storage_io_max_page_bytes_for_read |524288 |524288 |SESSION|Sets the maximum byte size of data pages that can be read from storage in a single I/O operation. |UInt64|
storage_io_min_bytes_for_seek |48 |48 |SESSION|Sets the minimum byte size of data that must be read from storage in a single I/O operation when seeking a new location in the data file. |UInt64|
storage_read_buffer_size |1048576 |1048576 |SESSION|Sets the byte size of the buffer used for reading data into memory. |UInt64|
timezone |UTC |UTC |SESSION|Sets the timezone. |String|
unquoted_ident_case_sensitive |0 |0 |SESSION|Determines whether Databend treats unquoted identifiers as case-sensitive. |UInt64|