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In this article:

  • HTTP request
  • Path parameters
  • Response
  • Permission
  • UserSettings
  • UserQuota
  • ConnectionManager
  1. API reference
  2. REST
  3. User
  4. Get

Managed Service for ClickHouse API, REST: User.Get

Written by
Yandex Cloud
Improved by
Updated at October 30, 2025
  • HTTP request
  • Path parameters
  • Response
  • Permission
  • UserSettings
  • UserQuota
  • ConnectionManager

Returns the specified ClickHouse User resource.

To get the list of available ClickHouse User resources, make a List request.

HTTP requestHTTP request

GET https://mdb.api.cloud.yandex.net/managed-clickhouse/v1/clusters/{clusterId}/users/{userName}

Path parametersPath parameters

Field

Description

clusterId

string

Required field. ID of the ClickHouse cluster the user belongs to.
To get the cluster ID, use a ClusterService.List request.

userName

string

Required field. Name of the ClickHouse User resource to return.
To get the name of the user, use a UserService.List request.

ResponseResponse

HTTP Code: 200 - OK

{
  "name": "string",
  "clusterId": "string",
  "permissions": [
    {
      "databaseName": "string"
    }
  ],
  "settings": {
    "readonly": "string",
    "allowDdl": "boolean",
    "allowIntrospectionFunctions": "boolean",
    "connectTimeout": "string",
    "connectTimeoutWithFailover": "string",
    "receiveTimeout": "string",
    "sendTimeout": "string",
    "idleConnectionTimeout": "string",
    "timeoutBeforeCheckingExecutionSpeed": "string",
    "insertQuorum": "string",
    "insertQuorumTimeout": "string",
    "insertQuorumParallel": "boolean",
    "selectSequentialConsistency": "boolean",
    "replicationAlterPartitionsSync": "string",
    "maxReplicaDelayForDistributedQueries": "string",
    "fallbackToStaleReplicasForDistributedQueries": "boolean",
    "distributedProductMode": "string",
    "distributedAggregationMemoryEfficient": "boolean",
    "distributedDdlTaskTimeout": "string",
    "distributedDdlOutputMode": "string",
    "skipUnavailableShards": "boolean",
    "useHedgedRequests": "boolean",
    "hedgedConnectionTimeoutMs": "string",
    "loadBalancing": "string",
    "preferLocalhostReplica": "boolean",
    "compileExpressions": "boolean",
    "minCountToCompileExpression": "string",
    "maxBlockSize": "string",
    "minInsertBlockSizeRows": "string",
    "minInsertBlockSizeBytes": "string",
    "maxInsertBlockSize": "string",
    "maxPartitionsPerInsertBlock": "string",
    "minBytesToUseDirectIo": "string",
    "useUncompressedCache": "boolean",
    "mergeTreeMaxRowsToUseCache": "string",
    "mergeTreeMaxBytesToUseCache": "string",
    "mergeTreeMinRowsForConcurrentRead": "string",
    "mergeTreeMinBytesForConcurrentRead": "string",
    "maxBytesBeforeExternalGroupBy": "string",
    "maxBytesBeforeExternalSort": "string",
    "groupByTwoLevelThreshold": "string",
    "groupByTwoLevelThresholdBytes": "string",
    "deduplicateBlocksInDependentMaterializedViews": "boolean",
    "localFilesystemReadMethod": "string",
    "remoteFilesystemReadMethod": "string",
    "priority": "string",
    "maxThreads": "string",
    "maxInsertThreads": "string",
    "maxMemoryUsage": "string",
    "maxMemoryUsageForUser": "string",
    "memoryOvercommitRatioDenominator": "string",
    "memoryOvercommitRatioDenominatorForUser": "string",
    "memoryUsageOvercommitMaxWaitMicroseconds": "string",
    "maxNetworkBandwidth": "string",
    "maxNetworkBandwidthForUser": "string",
    "maxTemporaryDataOnDiskSizeForQuery": "string",
    "maxTemporaryDataOnDiskSizeForUser": "string",
    "maxConcurrentQueriesForUser": "string",
    "forceIndexByDate": "boolean",
    "forcePrimaryKey": "boolean",
    "maxRowsToRead": "string",
    "maxBytesToRead": "string",
    "readOverflowMode": "string",
    "maxRowsToGroupBy": "string",
    "groupByOverflowMode": "string",
    "maxRowsToSort": "string",
    "maxBytesToSort": "string",
    "sortOverflowMode": "string",
    "maxResultRows": "string",
    "maxResultBytes": "string",
    "resultOverflowMode": "string",
    "maxRowsInDistinct": "string",
    "maxBytesInDistinct": "string",
    "distinctOverflowMode": "string",
    "maxRowsToTransfer": "string",
    "maxBytesToTransfer": "string",
    "transferOverflowMode": "string",
    "maxExecutionTime": "string",
    "timeoutOverflowMode": "string",
    "maxRowsInSet": "string",
    "maxBytesInSet": "string",
    "setOverflowMode": "string",
    "maxRowsInJoin": "string",
    "maxBytesInJoin": "string",
    "joinOverflowMode": "string",
    "maxColumnsToRead": "string",
    "maxTemporaryColumns": "string",
    "maxTemporaryNonConstColumns": "string",
    "maxQuerySize": "string",
    "maxAstDepth": "string",
    "maxAstElements": "string",
    "maxExpandedAstElements": "string",
    "maxParserDepth": "string",
    "minExecutionSpeed": "string",
    "minExecutionSpeedBytes": "string",
    "inputFormatValuesInterpretExpressions": "boolean",
    "inputFormatDefaultsForOmittedFields": "boolean",
    "inputFormatNullAsDefault": "boolean",
    "inputFormatWithNamesUseHeader": "boolean",
    "outputFormatJsonQuote_64bitIntegers": "boolean",
    "outputFormatJsonQuoteDenormals": "boolean",
    "dateTimeInputFormat": "string",
    "dateTimeOutputFormat": "string",
    "lowCardinalityAllowInNativeFormat": "boolean",
    "emptyResultForAggregationByEmptySet": "boolean",
    "formatRegexp": "string",
    "formatRegexpEscapingRule": "string",
    "formatRegexpSkipUnmatched": "boolean",
    "inputFormatParallelParsing": "boolean",
    "inputFormatImportNestedJson": "boolean",
    "formatAvroSchemaRegistryUrl": "string",
    "dataTypeDefaultNullable": "boolean",
    "httpConnectionTimeout": "string",
    "httpReceiveTimeout": "string",
    "httpSendTimeout": "string",
    "enableHttpCompression": "boolean",
    "sendProgressInHttpHeaders": "boolean",
    "httpHeadersProgressInterval": "string",
    "addHttpCorsHeader": "boolean",
    "cancelHttpReadonlyQueriesOnClientClose": "boolean",
    "maxHttpGetRedirects": "string",
    "httpMaxFieldNameSize": "string",
    "httpMaxFieldValueSize": "string",
    "quotaMode": "string",
    "asyncInsert": "boolean",
    "waitForAsyncInsert": "boolean",
    "waitForAsyncInsertTimeout": "string",
    "asyncInsertMaxDataSize": "string",
    "asyncInsertBusyTimeout": "string",
    "asyncInsertUseAdaptiveBusyTimeout": "boolean",
    "logQueryThreads": "boolean",
    "logQueryViews": "boolean",
    "logQueriesProbability": "number",
    "logProcessorsProfiles": "boolean",
    "useQueryCache": "boolean",
    "enableReadsFromQueryCache": "boolean",
    "enableWritesToQueryCache": "boolean",
    "queryCacheMinQueryRuns": "string",
    "queryCacheMinQueryDuration": "string",
    "queryCacheTtl": "string",
    "queryCacheMaxEntries": "string",
    "queryCacheMaxSizeInBytes": "string",
    "queryCacheTag": "string",
    "queryCacheShareBetweenUsers": "boolean",
    "queryCacheNondeterministicFunctionHandling": "string",
    "queryCacheSystemTableHandling": "string",
    "countDistinctImplementation": "string",
    "joinedSubqueryRequiresAlias": "boolean",
    "joinUseNulls": "boolean",
    "transformNullIn": "boolean",
    "insertNullAsDefault": "boolean",
    "joinAlgorithm": [
      "string"
    ],
    "anyJoinDistinctRightTableKeys": "boolean",
    "allowSuspiciousLowCardinalityTypes": "boolean",
    "flattenNested": "boolean",
    "memoryProfilerStep": "string",
    "memoryProfilerSampleProbability": "number",
    "maxFinalThreads": "string",
    "maxReadBufferSize": "string",
    "insertKeeperMaxRetries": "string",
    "doNotMergeAcrossPartitionsSelectFinal": "boolean",
    "ignoreMaterializedViewsWithDroppedTargetTable": "boolean",
    "enableAnalyzer": "boolean",
    "s3UseAdaptiveTimeouts": "boolean",
    "final": "boolean",
    "compile": "boolean",
    "minCountToCompile": "string",
    "asyncInsertThreads": "string",
    "asyncInsertStaleTimeout": "string"
  },
  "quotas": [
    {
      "intervalDuration": "string",
      "queries": "string",
      "errors": "string",
      "resultRows": "string",
      "readRows": "string",
      "executionTime": "string"
    }
  ],
  "connectionManager": {
    "connectionId": "string"
  }
}

A ClickHouse User resource. For more information, see the Developer's guide.

Field

Description

name

string

Required field. User name.

clusterId

string

Required field. Cluster ID.

permissions[]

Permission

User permissions.

settings

UserSettings

User settings.

quotas[]

UserQuota

Quotas assigned to the user.

connectionManager

ConnectionManager

Connection Manager connection configuration.

PermissionPermission

Field

Description

databaseName

string

Name of the database that the permission grants access to.

UserSettingsUserSettings

ClickHouse user settings. Supported settings are a subset of settings described
in ClickHouse documentation.

Field

Description

readonly

string (int64)

Restricts permissions for non-DDL queries. To restrict permissions for DDL queries, use allow_ddl instead.

  • 0 - no restrictions.
  • 1 - only read data queries are allowed.
  • 2 - read data and change settings queries are allowed.

Default value: 0.

For details, see ClickHouse documentation.

allowDdl

boolean

Allows or denies DDL queries (e.g., CREATE, ALTER, RENAME, etc).

Default value: true.

For details, see ClickHouse documentation.

allowIntrospectionFunctions

boolean

Enables or disables introspection functions for query profiling.

Default value: false.

For details, see ClickHouse documentation.

connectTimeout

string (int64)

Connection timeout in milliseconds.

Default value: 10000 (10 seconds).

For details, see ClickHouse documentation.

connectTimeoutWithFailover

string (int64)

The timeout in milliseconds for connecting to a remote server for a Distributed table engine.

Applies only if the cluster uses sharding and replication. If unsuccessful, several attempts are made to connect to various replicas.

Default value: 1000 (1 second).

For details, see ClickHouse documentation.

receiveTimeout

string (int64)

Receive timeout in milliseconds.

Default value: 300000 (5 minutes).

For details, see ClickHouse documentation.

sendTimeout

string (int64)

Send timeout in milliseconds.

Default value: 300000 (5 minutes).

For details, see ClickHouse documentation.

idleConnectionTimeout

string (int64)

Timeout to close idle TCP connections after specified time has elapsed, in milliseconds.

Default value: 3600000 (1 hour).

For details, see ClickHouse documentation.

timeoutBeforeCheckingExecutionSpeed

string (int64)

Checks that the speed is not too low after the specified time has elapsed, in milliseconds. It is checked that execution speed
is not less that specified in min_execution_speed parameter.

Default value: 60000 (1 minute).

For details, see ClickHouse documentation.

insertQuorum

string (int64)

Enables or disables the quorum writes. If the value is less than 2, then the quorum writes is disabled, otherwise it is enabled.

When used, write quorum guarantees that ClickHouse has written data to the quorum of insert_quorum replicas with no errors
until the insert_quorum_timeout expires. All replicas in the quorum are in the consistent state, meaning that they contain
linearized data from the previous INSERT queries. Employ write quorum, if you need the guarantees that the written data
would not be lost in case of one or more replicas failure.

You can use select_sequential_consistency setting to read the data written with write quorum.

Default value: 0.

For details, see ClickHouse documentation.

insertQuorumTimeout

string (int64)

Quorum write timeout in milliseconds.

If the write quorum is enabled in the cluster, this timeout expires and some data is not written to the insert_quorum replicas,
then ClickHouse will abort the execution of INSERT query and return an error. In this case, the client must send the query again
to write the data block into the same or another replica.

Default value: 600000 (10 minutes).

For details, see ClickHouse documentation.

insertQuorumParallel

boolean

Enables or disables parallelism for quorum INSERT queries.

Default value: true.

For details, see ClickHouse documentation.

selectSequentialConsistency

boolean

Determines the behavior of SELECT queries from replicated tables. If enabled, ClickHouse will terminate a query with error message in case
the replica does not have a chunk written with the quorum and will not read the parts that have not yet been written with the quorum.

Default value: true.

For details, see ClickHouse documentation.

replicationAlterPartitionsSync

string (int64)

Wait mode for asynchronous actions in ALTER queries on replicated tables.

  • 0 - do not wait for replicas.
  • 1 - only wait for own execution.
  • 2 - wait for all replicas.

Default value: 1.

For details, see ClickHouse documentation.

maxReplicaDelayForDistributedQueries

string (int64)

Max replica delay in milliseconds. If a replica lags more than the set value, this replica is not used and becomes a stale one.

Default value: 300000 (5 minutes).

For details, see ClickHouse documentation.

fallbackToStaleReplicasForDistributedQueries

boolean

Enables or disables query forcing to a stale replica in case the actual data is unavailable.
If enabled, ClickHouse will choose the most up-to-date replica and force the query to use the data in this replica.
This setting can be used when doing SELECT query from a distributed table that points to replicated tables.

Default value: true.

For details, see ClickHouse documentation.

distributedProductMode

enum (DistributedProductMode)

Determines the behavior of distributed subqueries.

Default value: DISTRIBUTED_PRODUCT_MODE_DENY.

For details, see ClickHouse documentation.

  • DISTRIBUTED_PRODUCT_MODE_UNSPECIFIED
  • DISTRIBUTED_PRODUCT_MODE_DENY: Prohibits using these types of subqueries (returns the "Double-distributed in/JOIN subqueries is denied" exception).
  • DISTRIBUTED_PRODUCT_MODE_LOCAL: Replaces the database and table in the subquery with local ones for the destination server (shard), leaving the normal IN/JOIN.
  • DISTRIBUTED_PRODUCT_MODE_GLOBAL: Replaces the IN/JOIN query with GLOBAL IN/GLOBAL JOIN.
  • DISTRIBUTED_PRODUCT_MODE_ALLOW: Allows the use of these types of subqueries.

distributedAggregationMemoryEfficient

boolean

Enables of disables memory saving mode when doing distributed aggregation.

When ClickHouse works with a distributed query, external aggregation is done on remote servers.
Enable this setting to achieve a smaller memory footprint on the server that sourced such a distributed query.

Default value: true.

For details, see ClickHouse documentation.

distributedDdlTaskTimeout

string (int64)

Timeout for DDL queries, in milliseconds.

Default value: 180000 (3 minutes).

For details, see ClickHouse documentation.

distributedDdlOutputMode

enum (DistributedDdlOutputMode)

Determines the format of distributed DDL query result.

Default value: DISTRIBUTED_DDL_OUTPUT_MODE_THROW.

For details, see ClickHouse documentation.

  • DISTRIBUTED_DDL_OUTPUT_MODE_UNSPECIFIED
  • DISTRIBUTED_DDL_OUTPUT_MODE_THROW: Returns result set with query execution status for all hosts where query is finished. If query has failed on some hosts, then it will rethrow the first exception.
    If query is not finished yet on some hosts and distributed_ddl_task_timeout exceeded, then it throws TIMEOUT_EXCEEDED exception.
  • DISTRIBUTED_DDL_OUTPUT_MODE_NONE: Like DISTRIBUTED_DDL_OUTPUT_MODE_THROW, but distributed DDL query returns no result set.
  • DISTRIBUTED_DDL_OUTPUT_MODE_NULL_STATUS_ON_TIMEOUT: Returns NULL as execution status in some rows of result set instead of throwing TIMEOUT_EXCEEDED if query is not finished on the corresponding hosts.
  • DISTRIBUTED_DDL_OUTPUT_MODE_NEVER_THROW: Do not throw TIMEOUT_EXCEEDED and do not rethrow exceptions if query has failed on some hosts.
  • DISTRIBUTED_DDL_OUTPUT_MODE_NONE_ONLY_ACTIVE: Like DISTRIBUTED_DDL_OUTPUT_MODE_NONE, but doesn't wait for inactive replicas of the Replicated database.
    With this mode it's impossible to figure out that the query was not executed on some replica and will be executed in background.
  • DISTRIBUTED_DDL_OUTPUT_MODE_NULL_STATUS_ON_TIMEOUT_ONLY_ACTIVE: Like DISTRIBUTED_DDL_OUTPUT_MODE_NULL_STATUS_ON_TIMEOUT, but doesn't wait for inactive replicas of the Replicated database.
  • DISTRIBUTED_DDL_OUTPUT_MODE_THROW_ONLY_ACTIVE: Like DISTRIBUTED_DDL_OUTPUT_MODE_THROW, but doesn't wait for inactive replicas of the Replicated database.

skipUnavailableShards

boolean

Enables or disables silent skipping of unavailable shards.

A shard is considered unavailable if all its replicas are also unavailable.

Default value: false.

For details, see ClickHouse documentation.

useHedgedRequests

boolean

Enables or disables hedged requests logic for remote queries.

It allows to establish many connections with different replicas for query. New connection is enabled in case existent connection(s) with replica(s)
were not established within hedged_connection_timeout or no data was received within receive_data_timeout. Query uses the first connection
which send non empty progress packet, other connections are cancelled.

Default value: true.

For details, see ClickHouse documentation.

hedgedConnectionTimeoutMs

string (int64)

Connection timeout for establishing connection with replica for Hedged requests.

Default value: 50.

For details, see ClickHouse documentation.

loadBalancing

enum (LoadBalancing)

Algorithm of replicas selection that is used for distributed query processing.

Default value: LOAD_BALANCING_RANDOM.

For details, see ClickHouse documentation.

  • LOAD_BALANCING_UNSPECIFIED
  • LOAD_BALANCING_RANDOM
  • LOAD_BALANCING_NEAREST_HOSTNAME
  • LOAD_BALANCING_IN_ORDER
  • LOAD_BALANCING_FIRST_OR_RANDOM
  • LOAD_BALANCING_ROUND_ROBIN

preferLocalhostReplica

boolean

Enable or disable preferable using the localhost replica when processing distributed queries.

Default value: true.

For details, see ClickHouse documentation.

compileExpressions

boolean

Enable or disable expression compilation to native code.

If you execute a lot of queries that contain identical expressions, then enable this setting.
As a result, such queries may be executed faster due to use of compiled expressions.

Use this setting in combination with min_count_to_compile_expression setting.

Default value: true for versions 25.5 and higher, false for versions 25.4 and lower.

For details, see ClickHouse documentation.

minCountToCompileExpression

string (int64)

How many identical expressions ClickHouse has to encounter before they are compiled.

For the 0 value compilation is synchronous: a query waits for expression compilation process to complete prior to continuing execution.
It is recommended to set this value only for testing purposes.

For all other values, compilation is asynchronous: the compilation process executes in a separate thread.
When a compiled expression is ready, it will be used by ClickHouse for eligible queries, including the ones that are currently running.

Default value: 3.

For details, see ClickHouse documentation.

maxBlockSize

string (int64)

Sets the recommended maximum number of rows to include in a single block when loading data from tables.

Blocks the size of max_block_size are not always loaded from the table: if ClickHouse determines that less data needs to be retrieved,
a smaller block is processed.

The block size should not be too small to avoid noticeable costs when processing each block. It should also not be too large to ensure that
queries with a LIMIT clause execute quickly after processing the first block. When setting max_block_size, the goal should be to avoid
consuming too much memory when extracting a large number of columns in multiple threads and to preserve at least some cache locality.

Default value: 65409.

For details, see ClickHouse documentation.

minInsertBlockSizeRows

string (int64)

Limits the minimum number of rows in a block to be inserted in a table by INSERT query. Blocks that are smaller than the specified value,
will be squashed together into the bigger blocks. If set to 0, block squashing is disabled.

Default value: 1048449.

For details, see ClickHouse documentation.

minInsertBlockSizeBytes

string (int64)

Limits the minimum number of bytes in a block to be inserted in a table by INSERT query. Blocks that are smaller than the specified value,
will be squashed together into the bigger blocks. If set to 0, block squashing is disabled.

Default value: 268402944.

For details, see ClickHouse documentation.

maxInsertBlockSize

string (int64)

The size of blocks (in a count of rows) to form for insertion into a table.

This setting only applies in cases when the server forms the blocks. For example, for an INSERT via the HTTP interface, the server parses
the data format and forms blocks of the specified size. But when using clickhouse-client, the client parses the data itself, and
the max_insert_block_size setting on the server does not affect the size of the inserted blocks. The setting also does not have a purpose
when using INSERT SELECT, since data is inserted using the same blocks that are formed after SELECT.

Default value: 1048449.

For details, see ClickHouse documentation.

maxPartitionsPerInsertBlock

string (int64)

When inserting data, ClickHouse calculates the number of partitions in the inserted block.
If the number of partitions is more than max_partitions_per_insert_block, ClickHouse throws an exception.

Default value: 100.

For details, see ClickHouse documentation.

minBytesToUseDirectIo

string (int64)

Limits the minimum number of bytes to enable unbuffered direct reads from disk (Direct I/O). If set to 0, Direct I/O is disabled.

By default, ClickHouse does not read data directly from disk, but relies on the filesystem and its cache instead. Such reading strategy
is effective when the data volume is small. If the amount of the data to read is huge, it is more effective to read directly from the disk,
bypassing the filesystem cache.

Default value: 0.

For details, see ClickHouse documentation.

useUncompressedCache

boolean

Determines whether to use the cache of uncompressed blocks, or not.

Using this cache can significantly reduce latency and increase the throughput when a huge amount of small queries is to be processed.
Enable this setting for the users who instantiates small queries frequently.

This setting has effect only for tables of the MergeTree family.

Default value: false.

For details, see ClickHouse documentation.

mergeTreeMaxRowsToUseCache

string (int64)

Limits the maximum size in rows of the request that can use the cache of uncompressed data. The cache is not used for requests larger than the specified value.

Use this setting in combination with use_uncompressed_cache setting.

Default value: 1048576.

For details, see ClickHouse documentation.

mergeTreeMaxBytesToUseCache

string (int64)

Limits the maximum size in bytes of the request that can use the cache of uncompressed data. The cache is not used for requests larger than the specified value.

Use this setting in combination with use_uncompressed_cache setting.

Default value: 2013265920 (1920 MiB).

For details, see ClickHouse documentation.

mergeTreeMinRowsForConcurrentRead

string (int64)

Limits the minimum number of rows to be read from a file to enable concurrent read.
If the number of rows to be read exceeds this value, then ClickHouse will try to use a few threads to read from a file concurrently.

This setting has effect only for tables of the MergeTree family.

Default value: 163840.

For details, see ClickHouse documentation.

mergeTreeMinBytesForConcurrentRead

string (int64)

Limits the number of bytes to be read from a file to enable concurrent read.
If the number of bytes to be read exceeds this value, then ClickHouse will try to use a few threads to read from a file concurrently.

This setting has effect only for tables of the MergeTree family.

Default value: 251658240 (240 MiB).

For details, see ClickHouse documentation.

maxBytesBeforeExternalGroupBy

string (int64)

Sets the threshold of RAM consumption (in bytes) after that the temporary data, collected during the GROUP BY operation,
should be flushed to disk to limit the RAM consumption. If set to 0, GROUP BY in the external memory is disabled.

By default, aggregation is done by employing hash table that resides in RAM. A query can result in aggregation of huge data
volumes that can lead to memory exhaustion and abortion of the query (see the max_memory_usage setting). For such queries,
you can use this setting to force ClickHouse to do flushing and complete aggregation successfully.

Default value: 0.

For details, see ClickHouse documentation.

maxBytesBeforeExternalSort

string (int64)

Sets the threshold of RAM consumption (in bytes) after that the temporary data, collected during the ORDER BY operation,
should be flushed to disk to limit the RAM consumption. If set to 0, ORDER BY in the external memory is disabled.

Default value: 0.

For details, see ClickHouse documentation.

groupByTwoLevelThreshold

string (int64)

Sets the threshold of the number of keys, after that the two-level aggregation should be used. 0 means threshold is not set.

Default value: 100000.

For details, see ClickHouse documentation.

groupByTwoLevelThresholdBytes

string (int64)

Sets the threshold of the number of bytes, after that the two-level aggregation should be used. 0 means threshold is not set.

Default value: 50000000.

For details, see ClickHouse documentation.

deduplicateBlocksInDependentMaterializedViews

boolean

Enables or disables the deduplication check for materialized views that receive data from replicated tables.

Default value: false.

For details, see ClickHouse documentation.

localFilesystemReadMethod

enum (LocalFilesystemReadMethod)

Method of reading data from local filesystem.

The LOCAL_FILESYSTEM_READ_METHOD_IO_URING is experimental and does not work for Log, TinyLog, StripeLog, File, Set and Join, and
other tables with append-able files in presence of concurrent reads and writes.

For details, see ClickHouse documentation.

  • LOCAL_FILESYSTEM_READ_METHOD_UNSPECIFIED
  • LOCAL_FILESYSTEM_READ_METHOD_READ
  • LOCAL_FILESYSTEM_READ_METHOD_PREAD_THREADPOOL
  • LOCAL_FILESYSTEM_READ_METHOD_PREAD
  • LOCAL_FILESYSTEM_READ_METHOD_NMAP
  • LOCAL_FILESYSTEM_READ_METHOD_IO_URING

remoteFilesystemReadMethod

enum (RemoteFilesystemReadMethod)

Method of reading data from remote filesystem.

Default value: REMOTE_FILESYSTEM_READ_METHOD_THREADPOOL.

For details, see ClickHouse documentation.

  • REMOTE_FILESYSTEM_READ_METHOD_UNSPECIFIED
  • REMOTE_FILESYSTEM_READ_METHOD_READ
  • REMOTE_FILESYSTEM_READ_METHOD_THREADPOOL

priority

string (int64)

Sets the priority of a query.

  • 0 - priorities are not used.
  • 1 - the highest priority.
  • and so on. The higher the number, the lower a query's priority.

If ClickHouse is working with the high-priority queries, and a low-priority query enters, then the low-priority query
is paused until higher-priority queries are completed.

Default value: 0.

For details, see ClickHouse documentation.

maxThreads

string (int64)

Limits the maximum number of threads to process the request. If set to 0, the number of threads is calculated automatically based on the number of available CPU cores.

The setting applies to threads that perform the same stages of the query processing pipeline in parallel. It does not take threads that read data from remote servers into account.

For details, see ClickHouse documentation.

maxInsertThreads

string (int64)

The maximum number of threads to execute the INSERT SELECT query.

Default value: 0.

For details, see ClickHouse documentation.

maxMemoryUsage

string (int64)

Limits the maximum memory usage (in bytes) for processing of a single user's query on a single server. 0 means unlimited.

This limitation is enforced for any user's single query on a single server.

If you use max_bytes_before_external_group_by or max_bytes_before_external_sort setting, then it is recommended to set
their values twice as low as max_memory_usage setting value.

Default value: 0.

For details, see ClickHouse documentation.

maxMemoryUsageForUser

string (int64)

Limits the maximum memory usage (in bytes) for processing of user's queries on a single server. 0 means unlimited.

This limitation is enforced for all queries that belong to one user and run simultaneously on a single server.

Default value: 0.

For details, see ClickHouse documentation.

memoryOvercommitRatioDenominator

string (int64)

It represents the soft memory limit when the hard limit is reached on the global level.
This value is used to compute the overcommit ratio for the query. 0 means skip the query.

Default value: 1073741824 (1 GiB).

For details, see ClickHouse documentation.

memoryOvercommitRatioDenominatorForUser

string (int64)

It represents the soft memory limit when the hard limit is reached on the user level.
This value is used to compute the overcommit ratio for the user. 0 means skip the query.

Default value: 1073741824 (1 GiB).

For details, see ClickHouse documentation.

memoryUsageOvercommitMaxWaitMicroseconds

string (int64)

Maximum time thread will wait for memory to be freed in the case of memory overcommit. If the timeout is reached and memory is not freed, an exception is thrown.

Default value: 5000000 (5 seconds).

For details, see ClickHouse documentation.

maxNetworkBandwidth

string (int64)

The maximum speed of data exchange over the network in bytes per second for a query. 0 means unlimited.

Default value: 0.

For details, see ClickHouse documentation.

maxNetworkBandwidthForUser

string (int64)

The maximum speed of data exchange over the network in bytes per second for all concurrently running user queries. 0 means unlimited.

Default value: 0.

For details, see ClickHouse documentation.

maxTemporaryDataOnDiskSizeForQuery

string (int64)

The maximum amount of data consumed by temporary files on disk in bytes for all concurrently running queries. 0 means unlimited.

Default value: 0.

For details, see ClickHouse documentation.

maxTemporaryDataOnDiskSizeForUser

string (int64)

The maximum amount of data consumed by temporary files on disk in bytes for all concurrently running user queries. 0 means unlimited.

Default value: 0.

For details, see ClickHouse documentation.

maxConcurrentQueriesForUser

string (int64)

The maximum number of simultaneously processed queries per user. 0 means unlimited.

Default value: 0.

For details, see ClickHouse documentation.

forceIndexByDate

boolean

Disables query execution if the index cannot be used by date.

This setting has effect only for tables of the MergeTree family.

Default value: false.

For details, see ClickHouse documentation.

forcePrimaryKey

boolean

Disables query execution if indexing by the primary key cannot be used.

This setting has effect only for tables of the MergeTree family.

Default value: false.

For details, see ClickHouse documentation.

maxRowsToRead

string (int64)

Limits the maximum number of rows that can be read from a table when running a query. 0 means unlimited.

Default value: 0.

For details, see ClickHouse documentation.

maxBytesToRead

string (int64)

Limits the maximum number of bytes (uncompressed data) that can be read from a table when running a query. 0 means unlimited.

Default value: 0.

For details, see ClickHouse documentation.

readOverflowMode

enum (OverflowMode)

Determines the behavior on exceeding limits while reading the data.

Default value: OVERFLOW_MODE_THROW.

For details, see ClickHouse documentation.

  • OVERFLOW_MODE_UNSPECIFIED
  • OVERFLOW_MODE_THROW: Abort query execution and return an error.
  • OVERFLOW_MODE_BREAK: Return a partial result.

maxRowsToGroupBy

string (int64)

Limits the maximum number of unique keys received from aggregation. 0 means unlimited.
This setting lets you limit RAM consumption when aggregating.

Default value: 0.

For details, see ClickHouse documentation.

groupByOverflowMode

enum (GroupByOverflowMode)

Determines the behavior on exceeding limits while doing aggregation.

Default value: GROUP_BY_OVERFLOW_MODE_THROW.

For details, see ClickHouse documentation.

  • GROUP_BY_OVERFLOW_MODE_UNSPECIFIED
  • GROUP_BY_OVERFLOW_MODE_THROW: Abort query execution and return an error.
  • GROUP_BY_OVERFLOW_MODE_BREAK: Return a partial result.
  • GROUP_BY_OVERFLOW_MODE_ANY: Continuing aggregation for the keys that got into the set, but do not add new keys to the set.

maxRowsToSort

string (int64)

Limits the maximum number of rows that can be read from a table for sorting. 0 means unlimited.
This setting lets you to limit RAM consumption when sorting

Default value: 0.

For details, see ClickHouse documentation.

maxBytesToSort

string (int64)

Limits the maximum number of bytes (uncompressed data) that can be read from a table for sorting. 0 means unlimited.
This setting lets you to limit RAM consumption when sorting

Default value: 0.

For details, see ClickHouse documentation.

sortOverflowMode

enum (OverflowMode)

Determines the behavior on exceeding limits while sorting.

Default value: OVERFLOW_MODE_THROW.

For details, see ClickHouse documentation.

  • OVERFLOW_MODE_UNSPECIFIED
  • OVERFLOW_MODE_THROW: Abort query execution and return an error.
  • OVERFLOW_MODE_BREAK: Return a partial result.

maxResultRows

string (int64)

Limits the number of rows in the result. 0 means unlimited.

This limitation is also checked for subqueries and parts of distributed queries that run on remote servers.

Default value: 0.

For details, see ClickHouse documentation.

maxResultBytes

string (int64)

Limits the result size in bytes (uncompressed data). 0 means unlimited.

Default value: 0.

For details, see ClickHouse documentation.

resultOverflowMode

enum (OverflowMode)

Determines the behavior on exceeding limits while forming result.

Default value: OVERFLOW_MODE_THROW.

For details, see ClickHouse documentation.

  • OVERFLOW_MODE_UNSPECIFIED
  • OVERFLOW_MODE_THROW: Abort query execution and return an error.
  • OVERFLOW_MODE_BREAK: Return a partial result.

maxRowsInDistinct

string (int64)

Limits the maximum number of different rows in the state, which is used for performing DISTINCT. 0 means unlimited.

Default value: 0.

For details, see ClickHouse documentation.

maxBytesInDistinct

string (int64)

Limits the maximum number of bytes (uncompressed data) in the state, which is used for performing DISTINCT. 0 means unlimited.

Default value: 0.

For details, see ClickHouse documentation.

distinctOverflowMode

enum (OverflowMode)

Determines the behavior on exceeding limits while performing DISTINCT.

Default value: OVERFLOW_MODE_THROW.

For details, see ClickHouse documentation.

  • OVERFLOW_MODE_UNSPECIFIED
  • OVERFLOW_MODE_THROW: Abort query execution and return an error.
  • OVERFLOW_MODE_BREAK: Return a partial result.

maxRowsToTransfer

string (int64)

Limits the maximum number of rows that can be passed to a remote server or saved in a temporary table when using GLOBAL IN|JOIN. 0 means unlimited.

Default value: 0.

For details, see ClickHouse documentation.

maxBytesToTransfer

string (int64)

Limits the maximum number of bytes (uncompressed data) that can be passed to a remote server or saved in a temporary table when using GLOBAL IN|JOIN.
0 means unlimited.

Default value: 0.

For details, see ClickHouse documentation.

transferOverflowMode

enum (OverflowMode)

Determines the behavior on exceeding limits while transfering data.

Default value: OVERFLOW_MODE_THROW.

For details, see ClickHouse documentation.

  • OVERFLOW_MODE_UNSPECIFIED
  • OVERFLOW_MODE_THROW: Abort query execution and return an error.
  • OVERFLOW_MODE_BREAK: Return a partial result.

maxExecutionTime

string (int64)

Limits the maximum query execution time in milliseconds. 0 means unlimited.

The timeout is checked and the query can stop only in designated places during data processing.

Default value: 0.

For details, see ClickHouse documentation.

timeoutOverflowMode

enum (OverflowMode)

Determines the behavior on exceeding limits of execution time.

Default value: OVERFLOW_MODE_THROW.

For details, see ClickHouse documentation.

  • OVERFLOW_MODE_UNSPECIFIED
  • OVERFLOW_MODE_THROW: Abort query execution and return an error.
  • OVERFLOW_MODE_BREAK: Return a partial result.

maxRowsInSet

string (int64)

Limits on the maximum number of rows in the set resulting from the execution of the IN section. 0 means unlimited.

Default value: 0.

For details, see ClickHouse documentation.

maxBytesInSet

string (int64)

Limits on the maximum number of bytes (uncompressed data) in the set resulting from the execution of the IN section. 0 means unlimited.

Default value: 0.

For details, see ClickHouse documentation.

setOverflowMode

enum (OverflowMode)

Determines the behavior on exceeding max_rows_in_set or max_bytes_in_set limit.

Default value: OVERFLOW_MODE_THROW.

For details, see ClickHouse documentation.

  • OVERFLOW_MODE_UNSPECIFIED
  • OVERFLOW_MODE_THROW: Abort query execution and return an error.
  • OVERFLOW_MODE_BREAK: Return a partial result.

maxRowsInJoin

string (int64)

Limits the maximum number of rows in the hash table that is used when joining tables. 0 means unlimited.

Default value: 0.

For details, see ClickHouse documentation.

maxBytesInJoin

string (int64)

Limits the maximum number of bytes in the hash table that is used when joining tables. 0 means unlimited.

Default value: 0.

For details, see ClickHouse documentation.

joinOverflowMode

enum (OverflowMode)

Determines the behavior on exceeding max_rows_in_join or max_bytes_in_join limit.

Default value: OVERFLOW_MODE_THROW.

For details, see ClickHouse documentation.

  • OVERFLOW_MODE_UNSPECIFIED
  • OVERFLOW_MODE_THROW: Abort query execution and return an error.
  • OVERFLOW_MODE_BREAK: Return a partial result.

maxColumnsToRead

string (int64)

Limits the maximum number of columns that can be read from a table in a single query. 0 means unlimited.
If the query requires to read more columns to complete, then it will be aborted.

Default value: 0.

For details, see ClickHouse documentation.

maxTemporaryColumns

string (int64)

Limits the maximum number of temporary columns that must be kept in RAM simultaneously when running a query, including constant columns. 0 means unlimited.
If the query generates more than the specified number of temporary columns in memory as a result of intermediate calculation, then it will be aborted.

Default value: 0.

For details, see ClickHouse documentation.

maxTemporaryNonConstColumns

string (int64)

Limits the maximum number of temporary columns that must be kept in RAM simultaneously when running a query, not including constant columns. 0 means unlimited.
If the query generates more than the specified number of temporary columns in memory as a result of intermediate calculation, then it will be aborted.

Default value: 0.

For details, see ClickHouse documentation.

maxQuerySize

string (int64)

Limits the size of the part of a query that can be transferred to RAM for parsing with the SQL parser, in bytes.

Data in the VALUES clause of INSERT queries is processed by a separate stream parser (that consumes O(1) RAM) and not affected by this restriction.

Default value: 262144 (256 KiB).

For details, see ClickHouse documentation.

maxAstDepth

string (int64)

Limits the maximum depth of query syntax tree.

Executing a big and complex query may result in building a syntax tree of enormous depth.
By using this setting, you can prohibit execution of over-sized or non-optimized queries for huge tables.

Default value: 1000.

For details, see ClickHouse documentation.

maxAstElements

string (int64)

Limits the maximum size of query syntax tree in number of nodes.

Executing a big and complex query may result in building a syntax tree of enormous size.
By using this setting, you can prohibit execution of over-sized or non-optimized queries for huge tables.

Default value: 50000.

For details, see ClickHouse documentation.

maxExpandedAstElements

string (int64)

Limits the maximum size of query syntax tree in number of nodes after expansion of aliases and the asterisk values.

Executing a big and complex query may result in building a syntax tree of enormous size.
By using this setting, you can prohibit execution of over-sized or non-optimized queries for huge tables.

Default value: 500000.

For details, see ClickHouse documentation.

maxParserDepth

string (int64)

Limits maximum recursion depth in the recursive descent parser. Allows controlling the stack size. If set to 0, recursion depth is unlimited.

Default value: 1000.

For details, see ClickHouse documentation.

minExecutionSpeed

string (int64)

Minimal execution speed in rows per second. Checked on every data block when timeout_before_checking_execution_speed expires.
If the execution speed is lower, an exception is thrown. 0 means unlimited.

Default value: 0.

For details, see ClickHouse documentation.

minExecutionSpeedBytes

string (int64)

Minimal execution speed in bytes per second. Checked on every data block when timeout_before_checking_execution_speed expires.
If the execution speed is lower, an exception is thrown. 0 means unlimited.

Default value: 0.

For details, see ClickHouse documentation.

inputFormatValuesInterpretExpressions

boolean

Enables or disables SQL parser if the fast stream parser cannot parse the data.

Enable this setting, if the data that you want to insert into a table contains SQL expressions.

For example, the stream parser is unable to parse a value that contains now() expression; therefore an INSERT query for this value
will fail and no data will be inserted into a table. With enabled SQL parser, this expression is parsed correctly: the now() expression
will be parsed as SQL function, interpreted, and the current date and time will be inserted into the table as a result.

This setting has effect only if you use Values format when inserting data.

Default value: true.

For details, see ClickHouse documentation.

inputFormatDefaultsForOmittedFields

boolean

Enables or disables replacing omitted input values with default values of the respective columns when performing INSERT queries.

Default value: true.

For details, see ClickHouse documentation.

inputFormatNullAsDefault

boolean

Enables or disables the initialization of NULL fields with default values, if data type of these fields is not nullable.

Default value: true.

For details, see ClickHouse documentation.

inputFormatWithNamesUseHeader

boolean

Enables or disables checking the column order when inserting data.

Default value: true.

For details, see ClickHouse documentation.

outputFormatJsonQuote_64bitIntegers

boolean

Enables or disables quoting of 64-bit integers in JSON output format.

If this setting is enabled, then 64-bit integers (UInt64 and Int64) will be quoted when written to JSON output
in order to maintain compatibility with the most of the JavaScript engines. Otherwise, such integers will not be quoted.

Default value: false for versions 25.8 and higher, true for versions 25.7 and lower.

For details, see ClickHouse documentation.

outputFormatJsonQuoteDenormals

boolean

Enables special floating-point values (+nan, -nan, +inf and -inf) in JSON output format.

Default value: false.

For details, see ClickHouse documentation.

dateTimeInputFormat

enum (DateTimeInputFormat)

Specifies which of date time parsers to use.

Default value: DATE_TIME_INPUT_FORMAT_BASIC.

For details, see ClickHouse documentation.

  • DATE_TIME_INPUT_FORMAT_UNSPECIFIED
  • DATE_TIME_INPUT_FORMAT_BEST_EFFORT
  • DATE_TIME_INPUT_FORMAT_BASIC
  • DATE_TIME_INPUT_FORMAT_BEST_EFFORT_US

dateTimeOutputFormat

enum (DateTimeOutputFormat)

Specifies which of date time output formats to use.

Default value: DATE_TIME_OUTPUT_FORMAT_SIMPLE.

For details, see ClickHouse documentation.

  • DATE_TIME_OUTPUT_FORMAT_UNSPECIFIED
  • DATE_TIME_OUTPUT_FORMAT_SIMPLE
  • DATE_TIME_OUTPUT_FORMAT_ISO
  • DATE_TIME_OUTPUT_FORMAT_UNIX_TIMESTAMP

lowCardinalityAllowInNativeFormat

boolean

Allows or restricts using the LowCardinality data type with the Native format.

LowCardinality columns (aka sparse columns) store data in more effective way, compared to regular columns, by using hash tables.
If data to insert suits this storage format, ClickHouse will place them into LowCardinality column.

If you use a third-party ClickHouse client that can't work with LowCardinality columns, then this client will not be able to correctly interpret
the result of the query that asks for data stored in LowCardinality column. Disable this setting to convert LowCardinality column to regular column
when creating the result, so such clients will be able to process the result.

Official ClickHouse client works with LowCardinality columns out-of-the-box.

Default value: true.

For details, see ClickHouse documentation.

emptyResultForAggregationByEmptySet

boolean

Enables or disables returning of empty result when aggregating without keys (with GROUP BY operation absent) on empty set (e.g., SELECT count(*) FROM table WHERE 0).

  • true - ClickHouse will return an empty result for such queries.
  • false - ClickHouse will return a single-line result consisting of NULL values for aggregation functions, in accordance with SQL standard.

Default value: false.

For details, see ClickHouse documentation.

formatRegexp

string

Regular expression (for Regexp format).

For details, see ClickHouse documentation.

formatRegexpEscapingRule

enum (FormatRegexpEscapingRule)

Field escaping rule (for Regexp format).

Default value: FORMAT_REGEXP_ESCAPING_RULE_RAW.

For details, see ClickHouse documentation.

  • FORMAT_REGEXP_ESCAPING_RULE_UNSPECIFIED
  • FORMAT_REGEXP_ESCAPING_RULE_ESCAPED
  • FORMAT_REGEXP_ESCAPING_RULE_QUOTED
  • FORMAT_REGEXP_ESCAPING_RULE_CSV
  • FORMAT_REGEXP_ESCAPING_RULE_JSON
  • FORMAT_REGEXP_ESCAPING_RULE_XML
  • FORMAT_REGEXP_ESCAPING_RULE_RAW

formatRegexpSkipUnmatched

boolean

Skip lines unmatched by regular expression (for Regexp format)

Default value: false.

For details, see ClickHouse documentation.

inputFormatParallelParsing

boolean

Enables or disables order-preserving parallel parsing of data formats. Supported only for TSV, TSKV, CSV and JSONEachRow formats.

Default value: true.

For details, see ClickHouse documentation.

inputFormatImportNestedJson

boolean

Enables or disables the insertion of JSON data with nested objects.

Default value: false.

For details, see ClickHouse documentation.

formatAvroSchemaRegistryUrl

string

Avro schema registry URL.

For details, see ClickHouse documentation.

dataTypeDefaultNullable

boolean

Allows data types without explicit modifiers NULL or NOT NULL in column definition will be Nullable.

Default value: false.

For details, see ClickHouse documentation.

httpConnectionTimeout

string (int64)

HTTP connection timeout, in milliseconds.

Default value: 1000 (1 second).

For details, see ClickHouse documentation.

httpReceiveTimeout

string (int64)

HTTP receive timeout, in milliseconds.

Default value: 30000 (30 seconds).

For details, see ClickHouse documentation.

httpSendTimeout

string (int64)

HTTP send timeout, in milliseconds.

Default value: 30000 (30 seconds).

For details, see ClickHouse documentation.

enableHttpCompression

boolean

Enables or disables data compression in HTTP responses.

By default, ClickHouse stores data compressed. When executing a query, its result is uncompressed.
Use this setting to command ClickHouse to compress the result when sending it via HTTP.

Enable this setting and add the Accept-Encoding: <compression method> HTTP header in a HTTP request to force compression of HTTP response from ClickHouse.

ClickHouse support the following compression methods: gzip, br and deflate.

Default value: false.

For details, see ClickHouse documentation.

sendProgressInHttpHeaders

boolean

Enables or disables progress notifications using X-ClickHouse-Progress HTTP header.

Default value: false.

For details, see ClickHouse documentation.

httpHeadersProgressInterval

string (int64)

Minimum interval between progress notifications with X-ClickHouse-Progress HTTP header, in milliseconds.

Default value: 100.

For details, see ClickHouse documentation.

addHttpCorsHeader

boolean

Adds CORS header in HTTP responses.

Default value: false.

For details, see ClickHouse documentation.

cancelHttpReadonlyQueriesOnClientClose

boolean

Cancels HTTP read-only queries (e.g. SELECT) when a client closes the connection without waiting for the response.

Default value: false.

For details, see ClickHouse documentation.

maxHttpGetRedirects

string (int64)

Limits the maximum number of HTTP GET redirect hops. If set to 0, no hops is allowed.

Default value: 0.

For details, see ClickHouse documentation.

httpMaxFieldNameSize

string (int64)

Maximum length of field name in HTTP header.

Default value: 131072.

For details, see ClickHouse documentation.

httpMaxFieldValueSize

string (int64)

Maximum length of field value in HTTP header.

Default value: 131072.

For details, see ClickHouse documentation.

quotaMode

enum (QuotaMode)

Quota accounting mode.

Default value: QUOTA_MODE_DEFAULT.

  • QUOTA_MODE_UNSPECIFIED
  • QUOTA_MODE_DEFAULT
  • QUOTA_MODE_KEYED
  • QUOTA_MODE_KEYED_BY_IP

asyncInsert

boolean

If enabled, data from INSERT query is stored in queue and later flushed to table in background.

Default value: false.

For details, see ClickHouse documentation.

waitForAsyncInsert

boolean

Enables or disables waiting for processing of asynchronous insertion. If enabled, server returns OK only after the data is inserted.

Default value: true.

For details, see ClickHouse documentation.

waitForAsyncInsertTimeout

string (int64)

Timeout for waiting for processing asynchronous inserts, in seconds.

Default value: 120 (2 minutes).

For details, see ClickHouse documentation.

asyncInsertMaxDataSize

string (int64)

The maximum size of the unparsed data in bytes collected per query before being inserted.

Default value: 10485760 (10 MiB).

For details, see ClickHouse documentation.

asyncInsertBusyTimeout

string (int64)

Maximum time to wait before dumping collected data per query since the first data appeared.

Default value: 200.

For details, see ClickHouse documentation.

asyncInsertUseAdaptiveBusyTimeout

boolean

Enables of disables adaptive busy timeout for asynchronous inserts.

Default value: true.

For details, see ClickHouse documentation.

logQueryThreads

boolean

Enables or disables query threads logging to the the system.query_thread_log table.
This setting has effect only when log_queries setting is enabled.

Default value: false.

For details, see ClickHouse documentation.

logQueryViews

boolean

Enables or disables query views logging to the the system.query_views_log table.

Default value: true.

For details, see ClickHouse documentation.

logQueriesProbability

number (double)

Log queries with the specified probability.

Default value: 1.

For details, see ClickHouse documentation.

logProcessorsProfiles

boolean

Enables or disables logging of processors level profiling data to the the system.processors_profile_log table.

Default value: false.

For details, see ClickHouse documentation.

useQueryCache

boolean

If turned on, SELECT queries may utilize the query cache.

Default value: false.

For details, see ClickHouse documentation.

enableReadsFromQueryCache

boolean

If turned on, results of SELECT queries are retrieved from the query cache.

Default value: true.

For details, see ClickHouse documentation.

enableWritesToQueryCache

boolean

If turned on, results of SELECT queries are stored in the query cache.

Default value: true.

For details, see ClickHouse documentation.

queryCacheMinQueryRuns

string (int64)

Minimum number of times a SELECT query must run before its result is stored in the query cache.

Default value: 0.

For details, see ClickHouse documentation.

queryCacheMinQueryDuration

string (int64)

Minimum duration in milliseconds a query needs to run for its result to be stored in the query cache.

Default value: 0.

For details, see ClickHouse documentation.

queryCacheTtl

string (int64)

After this time in seconds entries in the query cache become stale.

Default value: 60 (1 minute).

For details, see ClickHouse documentation.

queryCacheMaxEntries

string (int64)

The maximum number of query results the current user may store in the query cache. 0 means unlimited.

Default value: 0.

For details, see ClickHouse documentation.

queryCacheMaxSizeInBytes

string (int64)

The maximum amount of memory (in bytes) the current user may allocate in the query cache. 0 means unlimited.

Default value: 0.

For details, see ClickHouse documentation.

queryCacheTag

string

A string which acts as a label for query cache entries. The same queries with different tags are considered different by the query cache.

For details, see ClickHouse documentation.

queryCacheShareBetweenUsers

boolean

If turned on, the result of SELECT queries cached in the query cache can be read by other users.

It is not recommended to enable this setting due to security reasons.

Default value: false.

For details, see ClickHouse documentation.

queryCacheNondeterministicFunctionHandling

enum (QueryCacheNondeterministicFunctionHandling)

Controls how the query cache handles SELECT queries with non-deterministic functions like rand() or now().

Default value: QUERY_CACHE_NONDETERMINISTIC_FUNCTION_HANDLING_THROW.

For details, see ClickHouse documentation.

  • QUERY_CACHE_NONDETERMINISTIC_FUNCTION_HANDLING_UNSPECIFIED
  • QUERY_CACHE_NONDETERMINISTIC_FUNCTION_HANDLING_THROW: Throw an exception and don't cache the query result.
  • QUERY_CACHE_NONDETERMINISTIC_FUNCTION_HANDLING_SAVE: Cache the query result.
  • QUERY_CACHE_NONDETERMINISTIC_FUNCTION_HANDLING_IGNORE: Don't cache the query result and don't throw an exception.

queryCacheSystemTableHandling

enum (QueryCacheSystemTableHandling)

Controls how the query cache handles SELECT queries against system tables.

Default value: QUERY_CACHE_SYSTEM_TABLE_HANDLING_THROW.

For details, see ClickHouse documentation.

  • QUERY_CACHE_SYSTEM_TABLE_HANDLING_UNSPECIFIED
  • QUERY_CACHE_SYSTEM_TABLE_HANDLING_THROW: Throw an exception and don't cache the query result.
  • QUERY_CACHE_SYSTEM_TABLE_HANDLING_SAVE: Cache the query result.
  • QUERY_CACHE_SYSTEM_TABLE_HANDLING_IGNORE: Don't cache the query result and don't throw an exception.

countDistinctImplementation

enum (CountDistinctImplementation)

Specifies which of the uniq* functions should be used to perform the COUNT(DISTINCT ...) construction.

Default value: COUNT_DISTINCT_IMPLEMENTATION_UNIQ_EXACT.

For details, see ClickHouse documentation.

  • COUNT_DISTINCT_IMPLEMENTATION_UNSPECIFIED
  • COUNT_DISTINCT_IMPLEMENTATION_UNIQ
  • COUNT_DISTINCT_IMPLEMENTATION_UNIQ_COMBINED
  • COUNT_DISTINCT_IMPLEMENTATION_UNIQ_COMBINED_64
  • COUNT_DISTINCT_IMPLEMENTATION_UNIQ_HLL_12
  • COUNT_DISTINCT_IMPLEMENTATION_UNIQ_EXACT

joinedSubqueryRequiresAlias

boolean

Force joined subqueries and table functions to have aliases for correct name qualification.

Default value: true.

For details, see ClickHouse documentation.

joinUseNulls

boolean

Determines JOIN behavior on filling empty cells when merging tables. If enabled, the empty cells are filled with NULL.
Otherwise, the empty cells are filled with the default value of the corresponding field type.

Default value: false.

For details, see ClickHouse documentation.

transformNullIn

boolean

Enables equality of NULL values for IN operator.

By default, NULL values can't be compared because NULL means undefined value. Thus, comparison expr = NULL must always return false.
With this setting enabled NULL = NULL returns true for IN operator.

Default value: false.

For details, see ClickHouse documentation.

insertNullAsDefault

boolean

Enables or disables the insertion of default values instead of NULL into columns with not nullable data type.

If column type is not nullable and this setting is disabled, then inserting NULL causes an exception.
If column type is nullable, then NULL values are inserted as is, regardless of this setting.

Default value: true.

For details, see ClickHouse documentation.

joinAlgorithm[]

enum (JoinAlgorithm)

Specifies which JOIN algorithm to use.

Default value: JOIN_ALGORITHM_DIRECT,JOIN_ALGORITHM_PARALLEL_HASH,JOIN_ALGORITHM_HASH for versions 24.12 and higher, JOIN_ALGORITHM_DIRECT,JOIN_ALGORITHM_AUTO for versions from 23.8 to 24.11, JOIN_ALGORITHM_AUTO for versions 23.7 and lower.

For details, see ClickHouse documentation.

  • JOIN_ALGORITHM_UNSPECIFIED
  • JOIN_ALGORITHM_HASH
  • JOIN_ALGORITHM_PARALLEL_HASH
  • JOIN_ALGORITHM_PARTIAL_MERGE
  • JOIN_ALGORITHM_DIRECT
  • JOIN_ALGORITHM_AUTO
  • JOIN_ALGORITHM_FULL_SORTING_MERGE
  • JOIN_ALGORITHM_PREFER_PARTIAL_MERGE

anyJoinDistinctRightTableKeys

boolean

Enables legacy ClickHouse server behaviour in ANY INNER|LEFT JOIN operations.

Default value: false.

For details, see ClickHouse documentation.

allowSuspiciousLowCardinalityTypes

boolean

Allows or restricts using LowCardinality with data types with fixed size of 8 bytes or less.

Default value: false.

For details, see ClickHouse documentation.

flattenNested

boolean

Sets the data format of nested columns.

Default value: true.

For details, see ClickHouse documentation.

memoryProfilerStep

string (int64)

Sets the step of memory profiler. Whenever query memory usage becomes larger than every next step in number of bytes the memory profiler
will collect the allocating stacktrace and will write it into trace_log. If set to 0, memory profiler is disabled.

Default value: 4194304.

For details, see ClickHouse documentation.

memoryProfilerSampleProbability

number (double)

Collect random allocations and deallocations and write them into system.trace_log with MemorySample trace_type.
The probability is for every alloc/free regardless to the size of the allocation.

Default value: 0.

For details, see ClickHouse documentation.

maxFinalThreads

string (int64)

Sets the maximum number of parallel threads for the SELECT query data read phase with the FINAL modifier.

For details, see ClickHouse documentation.

maxReadBufferSize

string (int64)

The maximum size of the buffer to read from the filesystem.

Default value: 1048576 (1 MiB).

For details, see ClickHouse documentation.

insertKeeperMaxRetries

string (int64)

The setting sets the maximum number of retries for ClickHouse Keeper (or ZooKeeper) requests during insert into replicated MergeTree tables.
Only Keeper requests which failed due to network error, Keeper session timeout or request timeout are considered for retries.

Default value: 20.

For details, see ClickHouse documentation.

doNotMergeAcrossPartitionsSelectFinal

boolean

Enable or disable independent processing of partitions for SELECT queries with FINAL.

Default value: false.

For details, see ClickHouse documentation.

ignoreMaterializedViewsWithDroppedTargetTable

boolean

Ignore materialized views with dropped target table during pushing to views.

Default value: false.

For details, see ClickHouse documentation.

enableAnalyzer

boolean

Enables or disables new query analyzer.

Default value: true for versions 25.9 and higher, false for version 25.8, true for versions from 25.5 to 25.7, false for versions 25.4 and lower.

For details, see ClickHouse documentation.

s3UseAdaptiveTimeouts

boolean

Enables or disables adaptive timeouts for S3 requests.

  • true - for all S3 requests first two attempts are made with low send and receive timeouts.
  • false - all attempts are made with identical timeouts.

Default value: true.

For details, see ClickHouse documentation.

final

boolean

If enabled, automatically applies FINAL modifier to all tables in a query, to tables where FINAL is applicable,
including joined tables and tables in sub-queries, and distributed tables.

Default value: false.

For details, see ClickHouse documentation.

compile

boolean

The setting is deprecated and has no effect.

minCountToCompile

string (int64)

The setting is deprecated and has no effect.

asyncInsertThreads

string (int64)

The setting is deprecated and has no effect.

asyncInsertStaleTimeout

string (int64)

The setting is deprecated and has no effect.

UserQuotaUserQuota

ClickHouse quota representation. Each quota associated with an user and limits it resource usage for an interval.
For details, see ClickHouse documentation.

Field

Description

intervalDuration

string (int64)

Duration of interval for quota in milliseconds.

queries

string (int64)

The total number of queries. 0 means unlimited.

errors

string (int64)

The number of queries that threw exception. 0 means unlimited.

resultRows

string (int64)

The total number of rows given as the result. 0 means unlimited.

readRows

string (int64)

The total number of source rows read from tables for running the query, on all remote servers. 0 means unlimited.

executionTime

string (int64)

The total query execution time, in milliseconds (wall time). 0 means unlimited.

ConnectionManagerConnectionManager

Connection Manager connection configuration.

Field

Description

connectionId

string

ID of Connection Manager connection.

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